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Sunday, August 31, 2008

ASHRAE Handbook 2007 - HVAC Application (SI Edition)

ASHRAE Handbook 2007

HVAC Application (SI Edition)
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2008 ASHRAE Handbook - HVAC: Systems and Equipment (SI Edition)

2008 ASHRAE Handbook - HVAC: Systems and Equipment (SI Edition)
by ASHRAE
Publisher: Amer Society of Heating
Number Of Pages:
Publication Date: 2008-06
ISBN-10 / ASIN: 1933742348
ISBN-13 / EAN: 9781933742342
Binding: Hardcover

Highlights of Revisions for 2008

The 2008 ASHRAE Handbook—HVAC Systems and Equipment discusses various systems and the equipment (components or assemblies) that comprise them, and describes features and differences. This information helps system designers and operators in selecting and using equipment. An accompanying CD-ROM contains all the volume’s chapters in both I-P and SI units.

This edition includes two new chapters, described as follows:

Chapter 16, Ultraviolet Lamp Systems, includes a review of the fundamentals of UVC germicidal energy’s impact on microorganisms; how UVC lamps generate germicidal radiant energy; common approaches to the application of UVGI systems for upper-air room, in-duct, and surface cleansing; and a review of human safety and maintenance issues.
Chapter 17, Combustion Turbine Inlet Cooling (CTIC), provides a detailed discussion of how CTIC is used to help improve combustion turbine performance.

Some of the revisions and additions to the remainder of the volume are as follows:

Chapters 1 to 5 have each been revised to include new system and process flow diagrams, plus new discussion content on commissioning, building automation, maintenance management, sustainability/green design, security, and various systems (e.g., underfloor air distribution, chilled beams).
Chapter 7, Combined Heat and Power Systems, formerly entitled Cogeneration Systems and Engine and Turbine Drives, was reorganized, as well as updated for new technology.
Chapter 11, District Heating and Cooling, has new guidance on construction cost considerations, central plants, and distribution systems.
Chapter 12, Hydronic Heating and Cooling, has revised text and figures on all aspects of system design, including design procedure, water temperatures, heat transfer, distribution losses, constant- and variable-speed pumping, sizing control valves, and terminal units.
Chapter 18, Duct Construction, has new guidance for installation of flexible ducts.
Chapter 19, Room Air Distribution Equipment, was reorganized to coordinate with its companion chapter in HVAC Applications, with added content on equipment for stratified and partially stratified systems.
Chapter 24, Mechanical Dehumidifiers and Related Components, has new content on installation and service, indoor pool dehumidifiers, and application considerations for various equipment types.
Chapter 30, Automatic Fuel-Burning Systems, extensively reorganized and revised, contains updated information on new technology and code requirements.
Chapter 31, Boilers, has new material on condensing boilers, burner types, and operating and safety controls.
Chapter 32, Furnaces, has been thoroughly revised to reflect new technology and code requirements.
Chapter 34, Chimney, Vent, and Fireplace Systems, has been reorganized for clarity and has new content on designing fireplaces and their chimneys.
Chapter 36, Solar Energy Equipment, has been reorganized and has new content on photovoltaic systems and testing/rating.
Chapter 37, Compressors, has been reorganized and has updates on bearings and variable-speed drive technology.
Chapter 38, Condensers, contains revised content on air-cooled condensers, particularly on type descriptions, heat transfer, pressure drop, testing/rating, and installation and maintenance.
Chapter 40, Evaporative Air Cooling Equipment, has a rewritten section on indirect coolers.
Chapter 42, Liquid-Chilling Systems, has new discussion on both refrigerant selection and variable-flow chilled-water systems, as well as new and improved figures.
Chapter 44, Motors, Motor Controls, and Variable-Speed Drives, has updates for new technology and codes.
Chapter 48, Unitary Air Conditioners and Heat Pumps, has new content on multisplit units, variable-refrigerant-flow (VRF) equipment, certification, and sustainability.
This volume is published, both as a bound print volume and in electronic format on a CD-ROM, in two editions: one using inch-pound (I-P) units of measurement, the other using the International System of Units (SI).


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Tuesday, August 26, 2008

Pipe Work

PIPE WORK

Applications
Pipework is extensively used throughout an offshore installation to move fluids and gases from one location to another. It can generally be classified into the following three broad groupings:


1. Process
Used to transport the produced fluids and gases between processing units on the platform.

2. Service
Used to convey air, water, etc. to where it is needed for processing, life support and other services or utility functions.

3. Transportation
Usually large diameter pipelines as used to carry the production products from installation to installation or from the field to the onshore terminal.

Pumps and compressors are used to drive fluids and gases along pipes and valves to route and control the various substances and ensure that they are correctly segregated from each other.
The contents of the pipework are carried at widely varying temperatures, pressures and flow rates and,therefore, different types of pipework and associated equipment are required.
Because of the inherent danger in carrying the oil and gas associated with offshore operations, the design,installation, testing and inspection of certain pipework is ngourously controlled to exacting standards, so that leakage and bursting do not occur.


Design Features

1. Pipe Materials
Pipes are made in a number of materials, the particular one chosen being dependent upon pressure,temperature, resistance to corrosion, cost etc.
The most commonly used is carbon steel and for process work, this is normally of seamless construction.
It is strong, weldable, ductile, and usually cheaper than pipe made from other materials. It can stand temperatures up to 750ºF and is used whenever it can stand the duty required of it.

Other metals and alloys are sometimes used although they tend to be more expensive. Traditionally, corer and copper alloys were used for instrument lines although they have largely been replaced by stainless steel. They are still used for heat transfer equipment because of their high thermal conductivity.
Pipe can be lined or coated with materials such as vitreous substances, to provide resistance to chemical attack, corrosion, etc.

GRP (Glass Reinforced Plastic) is commonly used offshore on smaller service/potable water lines.

2. Pipe Sizes
The wall thickness of pipe used is determined by the pipework designer, taking into account the internal pressure, mechanical stresses to which it is subjected (i.e. dead/live loads and expansion stresses), the corrosion allowance and the safety factor to be applied. Wall thickness is determined in the ANSI system by ‘Schedule Number”, Schedule 40 being the most generally used.

Pipe size is determined by the design requirements of flow rate and head loss. Pipe sizes are identified by the Nominal Pipe Size (NPS). It is common practice to refer to Nominal Pipe Sizes 0-12 inches diameter as Nominal Bore (NB) and greater than 12 inches diameter as Outside Diameter (OD).

3. Methods of Joining Pipe
There are three main methods of joining pipes together and attaching fittings to them. Lines of 2 inch or larger are usually butt-welded, this being the most economic, leak-proof method. Smaller lines are usually joined by socket-welding or screwing.

Where larger diameter piping is required to join up with flanged vessels, valves and other equipment, or where the line has to be opened for periodic cleaning, bolted flange joints are used instead of butt-welding.
These are described more fully later.

Butt-Welded Systems Fittings

Elbows: These are used for making 45º or 90º changes in the direction of the pipe run. Normally used are “long radius”, in which the centre line radius of
curvature is equal to 1 1/2 times the nominal pipe size (MPS). Also available are “short radius” in which the centre line radius of curvature is equal to the NI’S.

Reducing Elbow
This makes a change in line size together with a change in direction.

Return
A return makes a 180 change in direction and is used in the construction of heating coils, etc.

Bends
Bends are made from straight pipe and common bending radii are 3 and 5 times the NI’S (indicated by 3R and SR respectively).

Reducer
This joins a larger pipe to a smaller one.

Flange
REFER THIS ALSO
Is a welding-neck flange (the most common type) and a slip-on flange. Flanges are fitted to the ends of pipes, valves, vessels, etc. to enable them to be connected by bolting.

Tee
REFER THIS ALSOA tee is used to make a 90 branch from a main pipe run. If the branch is smaller than the main run, a reducing tee is used.

Socket-Welded and Screwed Systems
Their uses are similar to those described for butt-welded fittings.

Flanged Joints
As described earlier, flanged joints are used whenever the pipes, valves, vessels, fittings etc. require to be connected together by bolting for ease of dismantling and reassembly.
This section describes types of flanged joints, which are commonly encountered.

Flat-Face
Most commonly used for mating with non-steel flanges on the bodies of pumps, valves, etc. The gaskets used (see Gaskets below) have an outside diameter equal to that of the flange itself. This ensures an even pressure distribution across the flange and reduces the risk of cracking of cast-iron or bronze flange on tightening or from plant vibration.

Raised Face
The raised face is the most common type of flange, in which the gasket covers only the raised faces.

Ring-Type Joint (RTJ)
This is a more expensive type of joint, but it is the best type for high temperature, high pressure and corrosive use

Gaskets
Gaskets are used to make a tight leak-proof seal between two joint surfaces. For pipe flanges, the common types of gaskets are the full-face and ring types which are used for flat-face and raised-face flanges respectively.
Gaskets are made from compressed asbestos, asbestos-filled metal (spiral-wound) and other materials dependent on the conditions to which they are subjected. Spiral-wound gaskets separate cleanly and can often be re-used.
They are useful, therefore, if the joint has to be frequently disconnected. The finish on the joint faces differs according to the type of gasket to be used. A “serrated” face is used with asbestos gaskets and a “smooth” face with spiral-wound ones.

Line Isolation and Blinding
Frequently, a completely leak-proof means of stopping the flow in a line has to be made. This may be because:
• The line, or a piece of equipment in it, has to be isolated to allow maintenance work to be carried out;
• A change in the process requires that the line be closed.

Valves do not offer complete security, as there may always be some degree of leakage and therefore, the line is closed by one of the following methods:
Spectacle Plate and Line Blind: The spectacle plate can be changed over quickly without disturbing the pipework and gives immediate visual evidence of whether the line is open or blinded. it is generally preferable to the simple line blind which is only used where frequent changing is not required.

Line Blind Valve: This allows a line to be quickly and simply blinded by a process operator. There are many types, but a typical one, a spool type line blind.

Removable Spool and Blind Flanges: This method involves removing a complete section of the line between two flanges (the spool) and fitting blind flanges to close the two ends of the line. This gives a very positive visual indication that the line is closed. Blind flanges are used to close any pipe end, vessel entry, etc.

Pipe Supports
Methods of supporting pipework vary greatly, but a selection of some of the more common is covered in this section.

Support: The term “support” refers to any device used to carry the weight of the pipework. Supports are usually made from structural steel.

Hanger: A hanger is a particular type of support by which pipework is suspended from a structure.
Hangers are usually adjustable for height

Anchor: An anchor is a rigid support, which prevents transmission of movement along pipework.
Tie: An arrangement of rods, bars, etc. to restrict movement of pipework.
Dummy Leg: An extension piece of pipe or steel section welded to an elbow.
Guide or Shoe: A means of allowing a pipe to move along its length whilst restricting its lateral movements.

Operation
4.2.6.1 Checks During Operation
The operation of a piping system is dictated by the operation of the equipment, which it connects. Nevertheless, care must be taken at all times to ensure that

• The piping is not operated beyond its design range of pressure and temperature;
• All joints are checked regularly for leaks and any leaks discovered are reported immediately;
• The piping is correctly isolated and purged, if necessary, before any maintenance work is performed on it;
• Line markings are clearly visible and re-made if not;
• Any abnormal vibration, damage, missing supports, etc are reported immediately.

Maintenance and Inspection
Legislative and other statutory requirements dictate the type and frequency of maintenance and inspection required on piping systems installed on offshore Installations. This maintenance and inspection is necessary to ensure that the Certificate of Fitness of the installation in question remains valid. The responsibility for ensuring that these requirements are met does not lie with the process operator.
However, he will be involved in isolating. purging, etc. at the time the maintenance and inspection are carried out.

Liquid Pipe Flow: Pressure Drop Calculation

LIQUID PIPE FLOW: PRESSURE DROP CALCULATION

Flow Of Liquid & Compressed Gases Through Circular Pipe
A common engineering problem to be able to determine the losses (analysis), or velocity (prediction) or the conduit size (design) of a piping system. Flow in a pipe is characterized by 7 parameters: Fluid viscosity & specific gravity, Pipe internal diameter, roughness & length, Flow rate/velocity & head loss/pressure drop. Based on which of the parameters are known, four types of computational problems are identified: namely the Calculation of i) Pressure drop, ii) Flow rate, iii) the Pipe internal diameter and iv) Pipe length. This task is accomplished by appropriate rearrangement, substitution and iterative solution of the following Equations:

Reynolds Number Re=VD/ν


where
Re = Reynolds Number
Q = average flow rate
V = average flow velocity
γ = fluid specific gravity
ν = kinetic viscosity, centistokes
D = pipe inside diameter
L = pipe length
ε = absolute internal pipe roughness
ƒ = friction factor
ΔZ = change in elevation
h = pressure head
hf = head loss due to pipe friction
Lm = head losses due to fittings, valves, etc(length equivalent)
P = pressure
g = gravitation acceleration

BIBLIOGRAPHY
* Menon ES; Piping Calculations Manual; McGraw Hill, New York, 2005.
* Hicks TG; Mechanical Engineering Formulas, Pocket Guide; McGraw Hill, New York, 2003, Chapter 10.
* Menon ES; Liquid Pipeline Hydraulics; Marcel Dekker, Inc, New York, 2004.
* Hicks TG (Editor); Handbook Of Mechanical Engineering Calculations; McGraw Hill, New York, 1998, Section 8.

Liquid Pipe Flow: Pipe Length Calculation

LIQUID PIPE FLOW: PIPE LENGTH CALCULATION

Flow Of Liquid & Compressed Gases Through Circular Pipe
A common engineering problem to be able to determine the losses (analysis), or velocity (prediction) or the conduit size (design) of a piping system. Flow in a pipe is characterized by 7 parameters: Fluid viscosity & specific gravity, Pipe internal diameter, roughness & length, Flow rate/velocity & head loss/pressure drop. Based on which of the parameters are known, four types of computational problems are identified: namely the Calculation of i) Pressure drop, ii) Flow rate, iii) the Pipe internal diameter and iv) Pipe length. This task is accomplished by appropriate rearrangement, substitution and iterative solution of the following Equations:

Reynolds Number Re=VD/ν


where
Re = Reynolds Number

Q = average flow rate
V = average flow velocity
γ = fluid specific gravity
ν = kinetic viscosity, centistokes
D = pipe inside diameter
L = pipe length
ε = absolute internal pipe roughness
ƒ = friction factor
ΔZ = change in elevation
h = pressure head
hf = head loss due to pipe friction
Lm = head losses due to fittings, valves, etc(length equivalent)
P = pressure
g = gravitation acceleration


BIBLIOGRAPHY
* Menon ES; Piping Calculations Manual; McGraw Hill, New York, 2005.

* Hicks TG; Mechanical Engineering Formulas, Pocket Guide; McGraw Hill, New York, 2003, Chapter 10.
* Menon ES; Liquid Pipeline Hydraulics; Marcel Dekker, Inc, New York, 2004.
* Hicks TG (Editor); Handbook Of Mechanical Engineering Calculations; McGraw Hill, New York, 1998, Section 8.

Monday, August 25, 2008

Liquid Pipe Flow: Pipe Diameter Calculation

LIQUID PIPE FLOW: PIPE DIAMETER CALCULATION

Flow Of Liquid & Compressed Gases Through Circular Pipe
A common engineering problem to be able to determine the losses (analysis), or velocity (prediction) or the conduit size (design) of a piping system. Flow in a pipe is characterized by 7 parameters: Fluid viscosity & specific gravity, Pipe internal diameter, roughness & length, Flow rate/velocity & head loss/pressure drop. Based on which of the parameters are known, four types of computational problems are identified: namely the Calculation of i) Pressure drop, ii) Flow rate, iii) the Pipe internal diameter and iv) Pipe length. This task is accomplished by appropriate rearrangement, substitution and iterative solution of the following Equations:

Reynolds Number Re=VD/ν












where
Re = Reynolds Number
Q = average flow rate
V = average flow velocity
γ = fluid specific gravity
ν = kinetic viscosity, centistokes
D = pipe inside diameterL = pipe length
ε = absolute internal pipe roughness
ƒ = friction factorΔZ = change in elevation
h = pressure head
hf = head loss due to pipe friction
Lm = head losses due to fittings, valves, etc. (length equivalent)
P = pressure
g = gravitation acceleration

BIBLIOGRAPHY
* Menon ES; Piping Calculations Manual; McGraw Hill, New York, 2005.
* Hicks TG; Mechanical Engineering Formulas, Pocket Guide; McGraw Hill, New York, 2003, Chapter 10.
* Menon ES; Liquid Pipeline Hydraulics; Marcel Dekker, Inc, New York, 2004.
* Hicks TG (Editor); Handbook Of Mechanical Engineering Calculations; McGraw Hill, New York, 1998, Section 8.

Liquid Pipe Flow: Flow Rte Calculation

LIQUID PIPE FLOW: FLOW RATE CALCULATION

Flow Of Liquid & Compressed Gases Through Circular Pipe
A common engineering problem to be able to determine the losses (analysis), or velocity (prediction) or the conduit size (design) of a piping system. Flow in a pipe is characterized by 7 parameters: Fluid viscosity & specific gravity, Pipe internal diameter, roughness & length, Flow rate/velocity & head loss/pressure drop. Based on which of the parameters are known, four types of computational problems are identified: namely the Calculation of i) Pressure drop, ii) Flow rate, iii) the Pipe internal diameter and iv) Pipe length. This task is accomplished by appropriate rearrangement, substitution and iterative solution of the following Equations:

Reynolds Number Re=VD/ν












where
Re = Reynolds Number
Q = average flow rate
V = average flow velocity
γ = fluid specific gravity
ν = kinetic viscosity, centistokes
D = pipe inside diameter
L = pipe length
ε = absolute internal pipe roughness
ƒ = friction factor
ΔZ = change in elevation
h = pressure head
hf = head loss due to pipe friction
Lm = head losses due to fittings, valves, etc. (length equivalent)
P = pressure
g = gravitation acceleration

BIBLIOGRAPHY
* Menon ES; Piping Calculations Manual; McGraw Hill, New York, 2005.
* Hicks TG; Mechanical Engineering Formulas, Pocket Guide; McGraw Hill, New York, 2003, Chapter 10.
* Menon ES; Liquid Pipeline Hydraulics; Marcel Dekker, Inc, New York, 2004.
* Hicks TG (Editor); Handbook Of Mechanical Engineering Calculations; McGraw Hill, New York, 1998, Section 8.

Fouling

FOULING

The deposition of paraffin, salt or scale on flowline wells can materially reduce the cross-sectional area of the pipe and severely restrict flow.

Paraffin can usually be removed by scraping or by pumping hot oil or condensate through the lines. Salt and/or scale similarly may require removal by a pipeline scraper pig, or in some cases by chemical treatment. These factors should be carefully considered when designing and sizing the flowlines. If either of these factors are suspected, it may be wise to weight the estimated cleaning frequency with the cost of installing slightly larger pipelines.

Flanges

FLANGES

Introduction
Flanges are normally used to connect sections of pipe, valves, vessels or other fittings by forming a seal with either a ring or flat type gasket. They are assembled with stud bolts, which when tightened, force the two flange faces towards each other on the gasket to form a pressure tight seal. Flanges in the oil industry are classified according to their construction, pressure rating and diameter.

The two classifications of flanges are:
1. ASA (ANSI) American Nation Standards Institute.
2. API American Petroleum Institute
4.3.2 API Classification of Flanges

There are three common types of API flanges: API 2000,3000,5000 and there are two high pressure series, API 10,000 and 15,000. The number of the series indicated corresponds to the maximum working pressure expressed in psi at a temperature of l00ºF.


This maximum working pressure is affected by temperature। The maximum working pressure of the flange will be reduced by a factor of 1.8% for each 50ºF increase in temperature above 100ºF to a maximum of 450’F. The following table gives the maximum working pressure as a function of temperature.

Pressure Ratings

1. Test And Working Pressures
The hydrostatic test pressure is equal to twice the maximum working pressures for flanges of diameter below or equal to 14 inches. The test pressure is equal to 1.5 times the maximum working pressure for flanges of diameter equal to or greater than 16 inches.

2. ASA Flanges
With the exception of the ASA 150 series, the number corresponds to the maximum working pressure of the flange in psi at a temperature of 85OºF for carbon steel flanges.
To obtain the working pressure of the flange at temperature from –20 to+ 100ºF, the number is multiplied by 2.4.

For example:
ASA 300 Max WP = 2.4 x 300 = 720psi
ASA 900 Max WP = 2.24 x 900 =2160psi

The following table gives the working pressures of all flanges in this classification. The hydrostatic test pressure is equal to 1.5 times the working pressure at 100ºF.

4. Flange Physical Characteristics
To avoid any confusion when describing or ordering flanges, the following information should be given:
1. Type ASA or API;
2. Description of connection:
a) Weld neck flange
b) Slip on welding flange
c) Threaded flange
d) Blind flange.
3. Nominal diameter;
4. Number in ASA or API classification;
5. Type of face and gasket;
6. Bore if necessary;
7. Type of steel used for manufacture.

5. Flange Make-Up
To ensure that the flange will form a good seal, care should be taken when making them up. The studs should first be made hand tight with the faces of the flanges parallel to each other. The studs should then be gradually tightened in the sequence shown in the diagram below.

6. Line Pipe
Line pipe is required by the oil and gas industry to convey oil, gas, water, chemicals, etc. in its operations.

The API with cooperation of the American Gas Association has developed specifications meeting the needs of the oil and gas industry for steel and wrought-iron line pipe and published these in API standards 5L and 5LX. These provide standard dimensions, strengths and performance properties and the required thread gauging practice to ensure complete interchangeability.

Friday, August 22, 2008

Standard Handbook for Civil Engineers

Standard Handbook for Civil Engineers
Ebook Title: Standard Handbook for Civil Engineers
Author: Jonathan T. Ricketts, M. Kent Loftin, Frederick S. Merritt
Publisher: McGraw-Hill Professional; 5 edition (December 29, 2003)
Hardcover: 1600 pages
Language: English
ISBN-10: 0071364730
ISBN-13: 978-0071364737



Ebook Description
A revision of the classic reference covering all important principles and techniques needed by practicing civil engineers. The 5th Edition incorporates changes in design and construction practices, especially in design specifications for construction materials, buildings and bridges, safety and health concerns, and the most current codes changes including ACI, AISC, ASTM, NDS for wood structures, etc. Standard Handbook for Civil Engineers, covers systems design, community and regional planning, the latest design methods for buildings, airports, highways, tunnels and bridges. It includes sections on construction equipment, construction management, materials, specifications, structural theory, geotechnical engineering, wood, concrete, steel design and construction.

This book provides code changes from the ACI, ASTM, & AISC, the most up-to-date specifications for wood construction, & recent EPA & OSHA regulations. Presents new methods for nondestructive testing of piles & applications of geosynthetics. Systems requirements: PC with 486 or higher processor, Microsoft Windows 3.1, Windows 95, or NT 3.51 or later, & 16 MB of RAM. CD-ROM. --This text refers to an out of print or unavailable edition of this title.
This new, completely updated, and expanded Fifth Edition features:
- The most recent code changes, including AIC, AISC, ASTM, NDS for Wood Structures, and more
- Current EPA and OSHA regulations
- Additional information on design build delivery systems
- Increased coverage of stormwater runoff
- Over 700 tables, formulas, and drawings to make every explanation and procedure crystal clear
- Sections on construction management; materials specifications; structural theory; wood and concrete, steel design and construction; and much more
- The latest design methods for buildings, airports, highways, tunnels, and bridges

Turn to this one-stop review of the field for simplified solutions to the hundreds of practical problems you face in your day-to-day civil engineering practice.

Ebook Review
Sci-Tech Book News : The fifth edition of this reference in civil engineering features coverage of recent code changes, including AIC, ASTM, and NDS for Wood Structures, and current EPA and OSHA regulations, plus expanded information on design build delivery systems and increased coverage of stormwater runoff. There is also new information on three-dimensional modeling of pile groups, cracking in high strength steel beams, intelligent transportation, and various types of wharf designs. Coverage encompasses fundamentals of civil engineering and the latest changes in design, construction, materials, and equipment in 23 different disciplines including systems design, geotechnical engineering, and community and regional planning. Ricketts is a consulting engineer.
Choice : ...contains much useful information and many equations, tables, and facts needed in many aspects of civil engineering...well written...easy to read...Highly recommended.
From the Back Cover : IF CIVIL ENGINEERS COULD HAVE ONLY ONE REFERENCE BOOK – THIS WOULD BE IT
About the AuthorJonathan T. Ricketts is a Consulting Engineer in Palm Beach Gardens, Florida, a registered engineer in several states, and the editor of McGraw-Hill's Building Design and Construction Handbook.
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The Handbook of Highway Engineering

The Handbook of Highway Engineering
Ebook Title: The Handbook of Highway Engineering

Author: T.F. Fwa
Publisher: CRC; 1 edition (September 28, 2005)
Hardcover: 888 pages
Language: EnglishI
SBN-10: 0849319862
ISBN-13: 978-0849319860


Ebook Description
Modern highway engineering reflects an integrated view of a road system's entire lifecycle, including any potential environmental impacts, and seeks to develop a sustainable infrastructure through careful planning and active management. This trend is not limited to developed nations, but is recognized across the globe. Edited by renowned authority T.F. Fwa, The Handbook of Highway Engineering provides a comprehensive, up-to-date treatment of all aspects of highway development and engineering. Its three sections range from consideration of socio-economic and environmental factors to design, construction, maintenance, and management. Beginning with financing, access management, environmental impacts, road safety, and noise, the book explores the expanded responsibilities of the modern highway engineer as well as the increasing trend toward privatization of project development and financing. The next section considers technical issues in highway and pavement engineering, including materials, new mechanistic-empirical design approaches, and new closed-form solutions for backcalculation as well as deflection and stress computation in multi-slab systems. Rounding out the discussion, the final section examines construction, management, performance evaluation including nondestructive testing, and a chapter devoted to highway asset management. Featuring contributions from eminent experts representing eight countries on four continents, The Handbook of Highway Engineering supplies all of the tools needed to manage the entire integrated process of modern highway development and engineering.


About The Author
T.F. Fwa is the Recipient of the ASCE 2005 Frank M. Masters Transportation Engineering Award For his innovative research on highway and airport pavements and excellence in teaching and professional activities to enhance transportation engineering. --Transportation and Development Institute of ASCE, 2005

The Electrical Engineering Handbook, 2Ed

The Electrical Engineering Handbook, Second Edition

Book Description
In 1993, the first edition of The Electrical Engineering Handbook set a new standard for breadth and depth of coverage in an engineering reference work. Now, this classic has been substantially revised and updated to include the latest information on all the important topics in electrical engineering today. Every electrical engineer should have an opportunity to expand his expertise with this definitive guide.In a single volume, this handbook provides a complete reference to answer the questions encountered by practicing engineers in industry, government, or academia. This well-organized book is divided into 12 major sections that encompass the entire field of electrical engineering, including circuits, signal processing, electronics, electromagnetics, electrical effects and devices, and energy, and the emerging trends in the fields of communications, digital devices, computer engineering, systems, and biomedical engineering. A compendium of physical, chemical, material, and mathematical data completes this comprehensive resource. Every major topic is thoroughly covered and every important concept is defined, described, and illustrated. Conceptually challenging but carefully explained articles are equally valuable to the practicing engineer, researchers, and students.A distinguished advisory board and contributors including many of the leading authors, professors, and researchers in the field today assist noted author and professor Richard Dorf in offering complete coverage of this rapidly expanding field. No other single volume available today offers this combination of broad coverage and depth of exploration of the topics. The Electrical Engineering Handbook will be an invaluable resource for electrical engineers for years to come.
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The Electronic Packaging Handbook

The Electronic Packaging Handbook
Reviewhighly recommendedenough detailprovides essential factural information on the design, manufacturing, and testing of electronic devices and systemsthis book is primarily for engineers and technicians involved in any aspect of design, production, testing, or packaging of electronic productsThe book ties together well with references between chapterswell written and editedeach chapter includes a section of bibliographic references and suggested readings.

--Dave Fish, Pandion Electronics, Inc., SMTnet.com

Book Description
The packaging of electronic devices and systems represents a significant challenge for product designers and managers. Performance, efficiency, cost considerations, dealing with the newer IC packaging technologies, and EMI/RFI issues all come into play. Thermal considerations at both the device and the systems level are also necessary. The Electronic Packaging Handbook, a new volume in the Electrical Engineering Handbook Series, provides essential factual information on the design, manufacturing, and testing of electronic devices and systems. Co-published with the IEEE, this is an ideal resource for engineers and technicians involved in any aspect of design, production, testing or packaging of electronic products, regardless of whether they are commercial or industrial in nature. Topics addressed include design automation, new IC packaging technologies, materials, testing, and safety. Electronics packaging continues to include expanding and evolving topics and technologies, as the demand for smaller, faster, and lighter products continues without signs of abatement. These demands mean that individuals in each of the specialty areas involved in electronics packaging-such as electronic, mechanical, and thermal designers, and manufacturing and test engineers-are all interdependent on each others knowledge. The Electronic Packaging Handbook elucidates these specialty areas and helps individuals broaden their knowledge base in this ever-growing field.
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Tuesday, August 19, 2008

The Properties of Gases and Liquids, 5Ed

ISBN: 0070116822
Title: The Properties of Gases and Liquids (5th. Edition)
Author: Bruce E. Poling John M. Prausnitz John P. O'Connell
Publisher: McGraw-Hill Professional
Publication Date: 2000-11-06
Number Of Pages: 768

Must-have reference for processes involving liquids, gases, and mixtures
Reap the time-saving, mistake-avoiding benefits enjoyed by thousands of chemical and process design engineers, research scientists, and educators. Properties of Gases and Liquids, Fifth Edition, is an all-inclusive, critical survey of the most reliable estimating methods in use today —now completely rewritten and reorganized by Bruce Poling, John Prausnitz, and John O'Connell to reflect every late-breaking development. You get on-the-spot information for estimating both physical and thermodynamic properties in the absence of experimental data with this property data bank of 600+ compound constants. Bridge the gap between theory and practice with this trusted, irreplaceable, and expert-authored expert guide — the only book that includes a critical analysis of existing methods as well as hands-on practical recommendations. Areas covered include pure component constants; thermodynamic properties of ideal gases, pure components and mixtures; pressure-volume-temperature relationships; vapor pressures and enthalpies of vaporization of pure fluids; fluid phase equilibria in multicomponent systems; viscosity; thermal conductivity; diffusion coefficients; and surface tension

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Power System and instrument

Schlumberger drilling CD's
With highly interactive show with visual and vocal effects illustrating drilling &other topics
related to oil productioncontents:

CD 10:
Power System and instrument
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Well logging, Mud logging and Drill stem tes

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CD 9:
Well logging, Mud logging and Drill stem tes
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Casing and Cementing

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CD 8:
Casing and Cementing
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Pipe Handling

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CD 7:
Pipe Handling
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Rotating Equipments & Mast and Substructure

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CD 6:
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Hoisting Equipments

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CD 5:
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Mud circulation and treating Equipments

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CD 4:
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Drilling Fluids and Mud Test

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CD 3
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BOP Equipments

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An introduction to drilling rigs and main components of drill string

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Tuesday, August 12, 2008

Piping [Lesson 1B]

Sizes and Ratings
Pipe, fittings, and valves must all fit together to form a piping system. To ensure uniform sizing and rating, a system of describing sizes and ratings has been developed.

Piping Sizes and Rating To understand piping installation, you must first know how piping is measured and rated.
Piping is manufactured and sold by two independent designations:
- Nominal size
- Schedule

When fully describing a pipe, both designations must be used. In describing a pipe in the field, usually only the nominal size is used. The schedule of a pipe in service cannot be determined visually without reading the marking.

Nominal Size Nominal size is approximately the inside diameter of the pipe or fitting, expressed in inches, or fractions of an inch. The smallest nominal pipe size is 1/8 inch. In larger nominal sizes, 48 inches is not uncommon. Nominal sizes increase by standard steps in size, such as 1/8, 1/4, 1/2, 3/4, 1, 1-1/2, 2, 3, 4, 6, 8 inch, and so-on.

A standard length or joint of any size pipe is 20 feet long.

Schedule
Pipe schedule is a number that expresses the ability of the pipe to resist pressure. The higher the schedule number, the greater the strength of the pipe. Pipe schedules are rated in standard units. Common schedules for piping are 20, 40, 80, 120, 160, and so-on. For the common nominal sizes up to 8 inches, standard-service pipe is rated schedule 40: below schedule 40 is light-duty piping and above schedule 40 is heavy duty piping. This designation is not true for the larger nominal sizes.


The schedule rating for piping is raised by increasing the wall thickness. The outside diameter for any nominal size pipe must remain fixed so the fittings will always fit. Therefore, to increase the schedule of a pipe, the inside diameter must be reduced to increase the wall thickness. A higher schedule number has less capacity to carry fluid than a lower schedule for any given nominal size.

Pipe Construction
Pipe is constructed by two common methods:
- Welded seam
- Seamless

Both types of construction have advantages and disadvantages.
Welded Seam Pipe
Welded seam pipe is rolled from a flat plate, and the seam is welded where the edges of the roll butt together. Welded seam pipe has uniform wall thickness but may have flaws in the weld. Welded seam pipe should not be used for corrosive liquids that could attack the weld flaws.

Seamless Pipe
Seamless pipe is extruded or forged from a solid billet of steel. It has the advantage of having no weld seam that can be attacked by corrosives. A disadvantage is the inside diameter is often oval-shaped, so the wall is not uniform in thickness. This could cause the pipe to be downgraded slightly in rating because of a thinner wall section.

Pipe Fittings
Pipe fittings are the connections used to join lengths of pipe, to change the direction of a pipe run, to reduce pipe size, or to branch a pipe run.

Some common pipe fittings are:
- Caps
- Couplings
- Ells
- Flanges
- Metering flanges
- Reducers
- Tees

Size and Rating of Pipe Fittings
Pipe fittings are sized by nominal size, the same method used for pipe.
They are rated by their working pressure, not by schedule. Examples of ratings are 150 lb, 300 lb, 400 lb, and 600 lb. The “lb” refers to the working pressure in psi (pounds per square inch). The rated “lbs” is at elevated temperature, as prescribed by ANSI (American National Standards Institute). At ambient temperatrue the strength of fittings is much higher than their rating.
Valves
Valves are inserted into piping runs to control and direct flow. Most valves are hand-operated and used to start and stop flows. For automatic process control, special valves with precision flow characteristics are remotely operated by automatic controllers.

Valves are sized and rated in the same way as fittings; that is, by nominal pipe size and by pressure rating. Standard service valves are rated at 150 lbs.

Installing Piping
Straight lengths of pipe are joined together end-to-end to make a pipe run. Fittings and valves are added to complete the run. All of this assembly must be sturdily supported, yet allow some limited movement for expansion and contraction. Because of this, piping installation is no simple thing.

How Piping, Fittings, and Valves are Joined
Joining Piping and Fittings
Steel piping and fittings are joined by two methods:
- Threaded connections
- Welded connections

Most process piping and fittings are joined by welding, especially if the piping is handling hazardous materials. Threaded connections have a tendency to crack and break at the threads when any stress is applied.
Piping lengths may be purchased with threaded ends or with beveled ends for welding. The same is true for fittings. Threaded fittings may have either male threads or female threads. (That is, they are either threaded on the outside or on the inside of the fitting wall.)

Sealing material is always applied to threaded connections before the connection is made. Sealing material may be a putty-like pipe joint compound or Teflon tape applied by wrapping the threads.
Joining Valves
Valves are seldom joined to piping by welding. Welding on valves can cause warping and leakage. Though weld valves are manufactured, most valves are installed with flanges or threaded connections. Flanges are cast as part of the valve. The valve flange mates with a flange welded to the connected piping and the valve is bolted into place. Before bolting, a gasket is inserted between the two flanges. Flanges will leak if care is not taken when they are assembled.

Pipe Supports Piping needs to be well supported to take the stress off of fittings and valves. Yet, it needs to be flexible to allow for expansion and contraction.

Pipe Racks Piping in a processing plant is laid out in parallel runs on elevated pipe racks or on piers. Pipe racks are beamed structures with posts and cross-beams at regular intervals. Tie beams and cross-bracing make the whole structure rigid.

Figure 1-2 illustrates a pipe rack.

A short length of “structural tee” is welded to the bottom of each pipe, where the pipe rests on the pipe rack. These “tee” shoes raise the pipe off the rack support beam so that insulation will not be crushed by the weight of the pipe.
Off-rack Pipe Suspension and Support Piping that descends a tower or traverses open space, away from the pipe rack, requires special support. The weight of the piping must not hang from flanges or connections or be allowed to flex into a bow. Vertical piping descending a tower is stabilized with side guides, and its weight rests on posts at the bottom. Springs and counterbalances are used to allow the pipe to expand. Horizontal runs of piping located away from the pipe rack are supported by pipe hangers, or on individual posts.

Piping [Lesson 1A]

Module Objectives
At the completion of this module, you will be able to:
- Describe piping and piping systems.
- Describe the basic components of piping systems.
- Describe how piping works.
- Describe the guidelines for operating piping systems.
- Describe how to maintain piping systems.


Module Introduction
Piping is a network or system of pipes, valves, and auxiliary equipment that channels fluids (liquids, gases, or fluidized solids) between plant vessels and equipment. As an operator, you must understand how piping affects process conditions. Piping obstructions and failures can affect operating safety and efficiency and be detrimental to product quality. In this module you will learn about piping and piping systems. You will also learn how to operate and perform preventive maintenance on piping systems.


Lesson 1 — ABOUT PIPING
Lesson Objectives
In order to complete this lesson, you must:
- Define fluid, pressure, and viscosity.
- Describe the three major functions of piping.
- Describe how piping, fittings, and valves are sized and rated.
- Describe how piping is installed


Lesson Introduction Piping systems are the conduits used to efficiently carry process fluids throughout a process plant. Understanding the basic concepts of piping systems will help you become a qualified, efficient, and safe operator.

In your work as a plant operator, you will use the basic concepts of piping every day. Understanding piping principles and functions will also aid you in your study of other operator training lessons.
In this lesson you will learn the basics of fluids, pressure, and viscosity, as well as piping functions, construction, and installation.



Fluids, Pressure, and Viscosity
In a process facility, piping directs the flow of fluids between the various vessels and equipment. To understand piping and its functions, you need to first understand fluids and the forces that act upon them.


Fluids Defined A fluid is any substance that flows. This, essentially, includes all substances that are not large undivided solids. Liquids, gases, and finely divided fluidized solids are all fluids. For the purposes of this module, fluids are able to flow through an enclosed piping system.


Definition of a Liquid A liquid is a fluid that flows freely but does not have a tendency to separate. Water is a good example. Internal forces hold a liquid together in a cohesive mass, while allowing it to flow and assume the shape of its container. A liquid does not appreciably change its volume when it is exposed to pressure variations.

Definition of a Gas A gas is an uncohesive fluid that expands to completely fill its container, and it has no independent shape or volume. Gases are compressible and can expand indefinitely. Gases have a proportional relationship between their quantity, volume , pressure, and temperature. If any one of these four variables change, a proportional change must occur in one or more of the other factors.

Definition of a Fluidized Solid A finely divided solid can be made to behave as a fluid if the mass of particles is aerated. Aeration is intermixing air, steam, or other gases into a bed of small solid particles so that the particles become separated and “lubricated.” While the aeration is maintained, the aerated mass can flow through piping, valves, and fittings as if it were a liquid. An example of a fluidized solid is the circulating catalyst in a Fluid Catalytic Cracking Unit

Pressure
Pressure is the force that a fluid exerts against the walls of the piping that contains it. Pressure is also the force that causes the fluid to move through the piping.


Pressure Defined Pressure is defined as a force per unit area. In the English measurement system, pressure is most often expressed as psi (pounds per square inch). This relates to the force, in pounds, that exerts itself against any square inch of area. Pressure exerts itself equally in all directions throughout any body of fluid. However, the weight of a fluid above any prescribed depth adds to the pressure at that level. This means that pressure increases with fluid depth.

Fluid Flow and Pressure Difference
Pressure Difference (dP) Pressure is the driving force to move a fluid in a piping system. To be more exact, fluid flow requires that a difference in pressure be established across the length of the pipe. The pressure must be greater at the upstream end of the pipe than at the downstream end. Pressure difference is often written as dP, d/P, or D P

NOTE
To move any fluid through a pipe, dP must be created across the pipe’s length. Either increase the upstream pressure, or decrease the downstream pressure, or both. As an example, a pump is a device that is used to increase the upstream pressure, creating dP and causing the fluid to flow.

Fluid Friction
Just as dP causes a fluid to flow, fluid friction opposes fluid flow. In any piping system, fluid friction increases with the rate of flow. When the flow begins for a given dP, flow increases until fluid friction balances the driving force. At that point, the rate of flow stops increasing and becomes constant.

NOTE
Fluid friction opposes fluid flow. Friction always increases as the flow rate increases. Therefore, for any given dP across a section of pipe, there is a steady maximum flow that results if no further restrictions are added.

Viscosity
There are two kinds of friction within any piping system:
- Wall friction between the fluid and the pipe walls
- Internal friction (or viscosity)

Viscosity, or the internal friction of a fluid, produces the greater resistance to flow. Fluids move through pipes in layers that slip by each other at different rates of flow. This shearing action creates friction. Viscosity increases with the “thickness” of the fluid. A thicker fluid has a higher viscosity (or resistance to flow).
In the pipe shown in Figure 1-1, the fluid is made to change direction with an ell-shaped fitting. In this case, the fluid turns 90° by friction with the wall of the ell. In the pipe on the right, a tee-shaped fitting is installed, and one side of the tee is plugged. Because the “dead” side of the tee is filled with fluid, the flow changes direction with friction against the “dead” fluid.
In this example the fluid friction in the tee is over nine times greater than it is in the ell, for the same flow rate. The greater friction is created by the viscosity of the fluid (or the fluid’s internal resistance to flow).
The Functions of Piping
Piping performs three major functions in the handling of fluids.
Functions The three major functions that piping performs are:
- Transporting fluids
- Containing fluid pressure
- Directing fluid flow and regulating flow rate

Transporting Fluids Piping is the conduit that contains and transports fluids throughout a processing plant. Piping can be branched to direct a fluid to several destinations simultaneously. It is the highway in which process fluids travel to reach vessels, heat exchangers, reactors, tanks, and other equipment within a process plant.
Containing Fluid Pressure Pressure is an important tool in a process. It is the energy used to move fluids through a process. It is able to concentrate a quantity of gas. And it assists chemical reactions in performing their transformations.

Piping can be designed to safely transport fluids that place extreme adverse conditions on the system. High pressure, high temperature, and corrosive fluids may be handled safely when proper design and metallurgy are used. The strength of the pipe wall determines if it can safely contain fluids under pressure.
Directing Fluid Flow and Regulating Flow Rate
As a fluid moves in a piping system, the flow may need to be manipulated. At times the flow needs to be:
- Stopped and isolated
- Regulated for rate of flow
- Routed through different piping
- Directed to a different destination
All of these operations are accomplished with valves. A valve is a special fitting with a moveable plug or gate in the flow path. When the valve is operated, the plug or gate stops or restricts the flow of fluid.

Gas Turbine Power Cycles [3]

4.5. Exhaust Heat Exchanges

Because the gas leaving the turbine is hotter than the gas leaving the compressor, it is
possible to heat up the air before it enters the combustion chamber by use of an exhaust gas
heat exchanger. This results in less fuel being burned in order to produce the same
temperature prior to the turbine and so makes the cycle more efficient. The layout of such a
plant is shown on fig.8.

In order to solve problems associated with this cycle, it is necessary to determine the temperature prior to the combustion chamber (T3).
A perfect heat exchanger would heat up the air so that T3 is the same as T5. It would also cool down the exhaust gas so that T6 becomes T2. In reality this is not possible so the
concept of THERMAL RATIO is used. This is defined as the ratio of the enthalpy given to the air to the maximum possible enthalpy lost by the exhaust gas. The enthalpy lost by the exhaust gas is
∆H = mgcpg(T5-T6)

This would be a maximum if the gas is cooled down such that T6 = T2. Of course in reality
this does not occur and the maximum is not achieved and the gas turbine does not perform
as well as predicted by this idealisation.
∆H(maximum) = ∆H = mgcpg(T5-T6)
The enthalpy gained by the air is ∆H(air) = macpa(T3-T2)
Hence the thermal ratio is T.R. = macpa(T3-T2)/ mgcpg(T5-T2)
The suffix ‘a’ refers to the air and g to the exhaust gas. Since the mass of fuel added in the
combustion chamber is small compared to the air flow we often neglect the difference in
mass and the equation becomes

WORKED EXAMPLE No.5
A gas turbine uses a pressure ratio of 7.5/1. The inlet temperature and pressure are
respectively 10oC and 105 kPa. The temperature after heating in the combustion
chamber is 1300 oC. The specific heat capacity cp for air is 1.005 kJ/kg K and for the
exhaust gas is 1.15 kJ/kg K. The adiabatic index is 1.4 for air and 1.33 for the gas.
Assume isentropic compression and expansion. The mass flow rate is 1kg/s.
Calculate the air standard efficiency if no heat exchanger is used and compare it to the
thermal efficiency when an exhaust heat exchanger with a thermal ratio of 0.88 is used.
SOLUTION
Referring to the numbers used on fig.8 the solution is as follows.
In order find the thermal efficiency, it is best to solve the energy transfers.
P(in)= mcpa(T2-T1) = 1 x 1.005 (503.6-283) = 221.7 kW
P(out) = mcpg(T4-T5) = 1 x 1.15 (1573-953.6) = 712.3 kW
P(nett) = P(out) - P(in) = 397.3 kW
Φ(in)combustion chamber) = mcpg(T4-T3)
Φ(in)= 1.15(1573-953.6) = 712.3 kW
ηth = P(nett)/Φ(in) = 494.2/712.3 = 0.693 or 69.3%

Self Assessment Exercise No. 5
1. A gas turbine uses a pressure ratio of 7/1. The inlet temperature and pressure are
respectively 10oC and 100 kPa. The temperature after heating in the combustion
chamber is 1000 oC. The specific heat capacity cp is 1.005 kJ/kg K and the adiabatic
index is 1.4 for air and gas. Assume isentropic compression and expansion. The mass
flow rate is 0.7 kg/s.
Calculate the net power output and the thermal efficiency when an exhaust heat
exchanger with a thermal ratio of 0.8 is used.
(Answers 234 kW and 57%)
2. A gas turbine uses a pressure ratio of 6.5/1. The inlet temperature and pressure are
respectively 15oC and 1 bar. The temperature after heating in the combustion chamber
is 1200 oC. The specific heat capacity cp for air is 1.005 kJ/kg K and for the exhaust
gas is 1.15 kJ/kg K. The adiabatic index is 1.4 for air and 1.333 for the gas. The
isentropic efficiency is 85% for both the compression and expansion process. The mass
flow rate is 1kg/s.
Calculate the thermal efficiency when an exhaust heat exchanger with a thermal ratio
of 0.75 is used.
(Answer 48.3%)

Worked Example No.6
A gas turbine has a free turbine in parallel with the turbine which drives the
compressor. An exhaust heat exchanger is used with a thermal ratio of 0.8. The
isentropic efficiency of the compressor is 80% and for both turbines is 0.85.
The heat transfer rate to the combustion chamber is 1.48 MW. The gas leaves the
combustion chamber at 1100oC. The air is drawn into the compressor at 1 bar and
25oC. The pressure after compression is 7.2 bar.
The adiabatic index is 1.4 for air and 1.333 for the gas produced by combustion. The
specific heat cp is 1.005 kJ/kg K for air and 1.15 kJ/kg K for the gas. Determine the
following.
i. The mass flow rate in each turbine.
ii. The net power output.
iii. The thermodynamic efficiency of the cycle.

Solution
T1 = 298 K
T2= 298(7.2)(1-1/1.4) = 524 K
T4 = 1373 K
T5 = 1373(1/7.2)(1-1/1.333) = 838.5 K
COMPRESSOR
ηi = 0.8 = (524-298)/(T2-298) hence T2= 580.5 K
TURBINES
Treat as one expansion with gas taking parallel paths.
ηi = 0.85 = (1373-T5)/(1373-838.5) hence T5 = 918.7 K
HEAT EXCHANGER
Thermal ratio = 0.8 = 1.005(T3-580.5)/1.15(918.7-580.5)
hence T3= 890.1 K
COMBUSTION CHAMBER
Φ(in)= mcp(T4-T3) = 1480 kW
1480 = m(1.15)(1373-890.1) hence m = 2.665 kg/s
COMPRESSOR
P(in) = mcp (T2-T1) = 2.665(1.005)(580.5-298) = 756.64 kW
TURBINE A
P(out) = 756.64 kW = mAcp(T4-T5)
756.64 = = 2.665(1.15)(1373-918.7) hence mA= 1.448 kg/s
Hence mass flow through the free turbine is 1.2168 kg/s
P(nett) = Power from free turbine =1.2168(1.15)(1373-918.7) = 635.7 kW
THERMODYNAMIC EFFICIENCY
ηth = P(nett)/Φ(in)= 635.7/1480 = 0.429 or 42.8 %
Self Assessment Exercise No. 6
1. List the relative advantages of open and closed cycle gas turbine engines.
Sketch the simple gas turbine cycle on a T-s diagram. Explain how the efficiency can be improved by the inclusion of a heat exchanger. In an open cycle gas turbine plant, air is compressed from 1 bar and 15oC to 4 bar. The
combustion gases enter the turbine at 800oC and after expansion pass through a heat
exchanger in which the compressor delivery temperature is raised by 75% of the
maximum possible rise. The exhaust gases leave the exchanger at 1 bar. Neglecting
transmission losses in the combustion chamber and heat exchanger, and differences in
compressor and turbine mass flow rates, find the following.
(i) The specific work output.
(ii) The work ratio
(iii) The cycle efficiency
The compressor and turbine polytropic efficiencies are both 0.84.
Compressor cp = 1.005 kJ/kg K γ= 1.4
Turbine cp = 1.148 kJ/kg K γ= 1.333

2. A gas turbine for aircraft propulsion is mounted on a test bed. Air at 1 bar and 293K
enters the compressor at low velocity and is compressed through a pressure ratio of 4
with an isentropic efficiency of 85%. The air then passes to a combustion chamber
where it is heated to 1175 K. The hot gas then expands through a turbine which drives
the compressor and has an isentropic efficiency of 87%. The gas is then further
expanded isentropically through a nozzle leaving at the speed of sound. The exit area
of the nozzle is 0.1 m2. Determine the following.
(i) The pressures at the turbine and nozzle outlets.
(ii) The mass flow rate.
(iii) The thrust on the engine mountings.
Assume the properties of air throughout.
The sonic velocity of air is given by
The temperature ratio before and after
the nozzle is given by
T(in)/T(out) = 2/(γ+1)