K L UNIVERSIT Y, GUNTURB.Tech. III year, Second Semester Academic Year: 2011-12 COURSE HANDOUT Date: 10-DEC-2011 Course Name : I.C.ENGUNES & GAS TURBINES Course Coor dinator : Dr.G.R.K.Sastry Course Detail : THEORY Lecture Hours : 45 Team of I nstructors : Dr.G.R.K.Sastry, K.Srinivasa Rao, V.Ranjit Kumar& L.Venu Gopal I. MECHANICAL ENG INEERI NG PROGRAMME OBJECTIVE: Mechanical engineers apply principles of physical science and mathematics to conceive, design, produce and operate the moving parts, components and machinery used in every aspect of modern life. From roc ket s, robots and automobil es to powe r pla nts , engine s, air -condi tio ning equi pme nt and biomechanical parts, mechanical engineers put energy and machines to work, and wherever there is motion, you’ll find evidence of their innovations. Today, they often use computer-aided design and computer simulation to ensure their products are reliable, efficient and economically sound. The spectrum of professional activity for the mechanical engineer runs from research through design and development to manufacturing and sales. II . PROGRAM EDUCATIONAL OB JECT IVES Upon completion of the mechanical engineering program our mechanical engineering students: (A) Wi ll pos sess a sound kno wl edg e and under standi ng of the fundamentals of mechanical engineering in the general streams of Design, Production, Thermal and Industrial Enginee ri ng, necessar y to be pr oducti ve engi nee rs in industry or government, and/or succeed in graduate or other professional schools. Will be able to formulate, analyze, and creatively solve multidisciplinary technical problems through the use of modern engineering tools, be they experimental, analytical or numerical. Wi ll develop and use lif elong lea rni ng skills to tak e advant age of professional developme nt opportunities in their disciplines, develop new knowledge and skills, pursue new areas of expertise or careers, adapt to changing global markets and workforce trends. Will be able to communicate clearly and effectively with fellow engineers, employers, and the general public. Will posse ss the ski ll s needed to ful fi ll their profe ssional dut ie s and responsi bi li ti es in teamwork, collegiality, ethics, technical leadership, business acumen and lifelong learning. Will understand the economical, societal and environmental impact and ethical and professional responsibilities of a mechanical engineer and Graduates willengage in professional service by L-T-P 4-1-2
This document is posted to help you gain knowledge. Please leave a comment to let me know what you think about it! Share it to your friends and learn new things together.
This course studies the fundamentals of how the design and operation of internal combustion engines
affect their performance, operation, fuel requirements, and environmental impact. Topics include fluidflow, thermodynamics, combustion, heat transfer and friction phenomena, and fuel properties, with
reference to engine power, efficiency, and emissions. Students examine the design features and
operating characteristics of different types of internal combustion engines: spark-ignition, diesel
stratified-charge, and mixed-cycle engines. Class includes lab project in the Engine Laboratory.
VI. COURSE OBJECTIVES:
1.To make students familiar with the design and operating characteristics of modern internal
combustion engines
2.To apply analytical techniques to the engineering problems and performance analysis of internal
combustion engines
3.To study the thermodynamics, combustion, heat transfer, friction and other factors affecting engine
power, efficiency and emissions
4.To introduce students to the environmental and fuel economy challenges facing the internal
combustion engine
5.To introduce students to future internal combustion engine technology and market trends
.
VII. COURSE OUTCOMES:
At the end of the course the student will be able to to do the following. :
1. Differentiate among different internal combustion engine designs
2. Recognize and understand reasons for differences among operating characteristics of differen
engine types and designs
3. Given an engine design specification, predict performance and fuel economy trends with good
accuracy
4. Based on an in-depth analysis of the combustion process, predict concentrations of primary
exhaust pollutants
5. Exposure to the engineering systems needed to set-up and run engines in controlled laboratory
environments
6. Develop skills to run engine dynamometer experiments
All internal combustion engines depend on the combustion of a chemical fuel, typically with oxygen
from the air (though it is possible to inject nitrous oxide in order to do more of the same thing and gain a
power boost). The combustion process typically results in the production of a great quantity of heat, as
well as the production of steam and carbon dioxide an2d other chemicals at very high temperature; the
temperature reached is determined by the chemical make up of the fuel and oxidisers (see stoichiometry)
as well as by the compression and other factors.Gasoline engine ignition systems generally rely on a
combination of a lead–acid battery and an induction coil to provide a high-voltage electric spark to ignite
the air-fuel mix in the engine's cylinders. This battery is recharged during operation using an electricity-
generating device such as an alternator or generator driven by the engine. Gasoline engines take in a
mixture of air and gasoline and compress it to not more than 12.8 bar (1.28 MPa), then use a spark plug to
ignite the mixture when it is compressed by the piston head in each cylinder.
COMBUSTION IN CI ENGINE:
Diesel engines and HCCI (Homogeneous charge compression ignition) engines, rely solely on heat
and pressure created by the engine in its compression process for ignition. The compression level that
occurs is usually twice or more than a gasoline engine. Diesel engines will take in air only, and shortly
before peak compression, a small quantity of diesel fuel is sprayed into the cylinder via a fuel injector that
allows the fuel to instantly ignite. HCCI type engines will take in both air and fuel but continue to rely on
an unaided auto-combustion process, due to higher pressures and heat. This is also why diesel and HCCI
engines are more susceptible to cold-starting issues, although they will run just as well in cold weather
once started. Light duty diesel engines with indirect injection in automobiles and light trucks employ
glowplugs that pre-heat the combustion chamber just before starting to reduce no-start conditions in coldweather. Most diesels also have a battery and charging system; nevertheless, this system is secondary and
is added by manufacturers as a luxury for the ease of starting, turning fuel on and off (which can also be
done via a switch or mechanical apparatus), and for running auxiliary electrical components and
accessories. Most new engines rely on electrical and electronic engine control units (ECU) that also adjust
the combustion process to increase efficiency and reduce emissions.
KNOCK RATING OF FUELS:
The knock tendency in spark ignition engines of binary mixtures of hydrogen, ethane, propane and n-
butane is examined in a CFR engine for a range of mixture composition, compression ratio, spark timing
and equivalence ratio. It is shown that changes in the knock characteristics of binary mixtures of hydrogen
with methane are sufficiently different from those of the binary mixtures of the other gaseous fuels with
methane that renders the use of the methane number of limited utility. However, binary mixtures of n-
butane with methane may offer a better alternative. Small changes in the concentration of butane produce
almost linearly significant changes in both the values of the knock limited compression ratio for fixed
spark timing and the knock limited spark timing for a fixed compression ratio.
compressors, known as superchargers, have also been used to boost the power of automotive reciprocating
engines by compressing the intake air, though these are very rare.
UNIT-V
GAS TURBINES:
A gas turbine, also called a combustion turbine, is a type of internal combustion engine. It has an upstream
rotating compressor coupled to a downstream turbine, and a combustion chamber in-between.
Energy is added to the gas stream in the combustor, where fuel is mixed with air and ignited. In the
high pressure environment of the combustor, combustion of the fuel increases the temperature. The
products of the combustion are forced into the turbine section. There, the high velocity and volume of the
gas flow is directed through a nozzle over the turbine's blades, spinning the turbine which powers the
compressor and, for some turbines, drives their mechanical output. The energy given up to the turbinecomes from the reduction in the temperature and pressure of the exhaust gas.
Energy can be extracted in the form of shaft power, compressed air or thrust or any combination of
these and used to power aircraft, trains, ships, generators, or even tanks.
JET & ROCKET PROPULSION:
A jet engine is a reaction engine that discharges a fast moving jet to generate thrust by jet propulsion and
in accordance with Newton's laws of motion. This broad definition of jet engines includes turbojets
turbofans, rockets, ramjets, pulse jets. In general, most jet engines are internal combustion engines[1] but
non-combusting forms also exist.
In common parlance, the term jet engine loosely refers to an internal combustion airbreathing jet
engine (a duct engine). These typically consist of an engine with a rotary (rotating) air compressor
powered by a turbine ("Brayton cycle"), with the leftover power providing thrust via a propelling nozzle
These types of jet engines are primarily used by jet aircraft for long distance travel. Early jet aircraft used
turbojet engines which were relatively inefficient for subsonic flight. Modern subsonic jet aircraft usually
use high-bypass turbofan engines which give high speeds, as well as (over long distances) fuel efficiency
that is about as good as piston and propeller aeroengines
A rocket engine, or simply "rocket", is a jet engine[1] that uses only propellant mass for forming its
high speed propulsive jet. Rocket engines are reaction engines and obtain thrust in accordance with
Newton's third law. Since they need no external material to form their jet, rocket engines can be used for