INTERNAL COMBUSTION ENGINE ASPECTS

MR.Vinod ajnabi : 

MR.Vinod ajnabi FROM KRISHNA ENGG COLLEGE GAZIABAD(U.P) KRISHNA ENGG COLLEGE GAZIABAD(U.P)

OUT LINE : 

OUT LINE INTRODUCTION THERMAL STRENGTH VIBRATION ADVANTAGE LIMITATION

INTRODUCTION : 

INTRODUCTION The internal combustion engine is an engine in which the combustion of a fuel (generally, fossil fuel) occurs with an oxidizer (usually air) in a combustion chamber. The internal combustion engine (or ICE) is quite different from external combustion engines, such as steam or Stirling engines, in which the energy is delivered to a working fluid not consisting of, mixed with or contaminated by Working fluids can be air, hot water, pressurised water or even liquid sodium, heated in some kind of boiler by fossil fuel, wood-burning, nuclear, solar combustion products

CONTINUE : 

CONTINUE I.C ENGINE

THERMAL : 

THERMAL THERMAL CYCLE MECHANICAL EFFECIENCY STROKE OF ENGINE

THERMAL CYCLE : 

THERMAL CYCLE OTTO CYCLE DESIEL CYCLE ATKINSON CYCLE JOULE OR BRAYTON CYCLE CARNOT CYCLE STRILING CYCLE

OTTO CYCLE : 

OTTO CYCLE

CONTINUE : 

CONTINUE

DESIEL CYCLE : 

DESIEL CYCLE

ATKINSON CYCLE : 

ATKINSON CYCLE

JOULE OR BRAYTON : 

JOULE OR BRAYTON

CONTINUEBRAYTON CYCLE ENGINE : 

CONTINUEBRAYTON CYCLE ENGINE

CARNOT CYCLE CYCLE : 

CARNOT CYCLE CYCLE

STRILING CYCLE : 

STRILING CYCLE

CONTINUESECTION VIEW OFSRILING ENGINE : 

CONTINUESECTION VIEW OFSRILING ENGINE

CONTINUESTRLING ENGINE MODEL : 

CONTINUESTRLING ENGINE MODEL

MECHANICAL EFFECIENCY : 

MECHANICAL EFFECIENCY Mechanical efficiency n:n = (Pb / Pig) = 1-(Pf / Pig)Where Pb is the brake power, Pig is gross indicated power, and Pf the friction power.

STROKE OF ENGINE : 

STROKE OF ENGINE TWO STROKE (DESIEL,PETROL) FOUR STROKE (DESIEL,PETROL) SIX STROKE

TWO STROKE ENGINE : 

TWO STROKE ENGINE

FOUR STROKE ENGINE : 

FOUR STROKE ENGINE

BASED ON STRENTH : 

BASED ON STRENTH CYLINDER OF ENGINE CARK SHAFT PISTON CONNECTTING ROD WRUST PIN PISTON RING FLYWHEEL ROCKER ARM MECHANISM AND OTHER MECHANICAL DEVICE LIKE ,GEAR,PINOIN,GEAR BOX,CLUCTH,ETC

STRENGTH OF CYLINDER : 

STRENGTH OF CYLINDER Automobile-engine cylinders generally cast of close-grained gray iron approximating the following composition. Silicon 1.9 to 2.2% Sulphur not over 0.12% Phosphorus not over 0.15% Manganese 0.6 to 0.9% Combined carbon 0.35 to 0.55% Total carbon 3.2 to 3.4%

STRENGTH OF CRANK SHAFT : 

STRENGTH OF CRANK SHAFT The shaft is subjected to various forces but generally needs to be analysed in two positions. Firstly, failure may occur at the position of maximum bending; this may be at the centre of the crank or at either end. In such a condition the failure is due to bending and the pressure in the cylinder is maximal. Second, the crank may fail due to twisting, so the conrod needs to be checked for shear at the position of maximal twisting. The pressure at this position is the maximal pressure, but only a fraction of maximal pressure.

STRENGTH OF PISTON : 

STRENGTH OF PISTON Cast Iron piston   Steel piston Aluminium piston,

STRENGTH OF CONNECTING ROD : 

STRENGTH OF CONNECTING ROD

STRENGTH OF PISTON RING : 

STRENGTH OF PISTON RING Cast iron Cast iron alloyed for piston rings Nodular cast iron alloyed for piston rings Bronze Aluminum Bronze Phosphor Bronze Steel Stainless Steels for use in high temperatures

STRENGTH OF FLYWHEEL : 

STRENGTH OF FLYWHEEL High energy materials Flywheel from stationary engine. Note the castellated rim which was used to rotate the engine to the correct starting position by means of a lever. For a given flywheel design, it can be derived from the above equations that the kinetic energy is proportional to the ratio of the hoop stress to the material density and to the mass. could be called the specific tensile strength. The flywheel material with the highest specific tensile strength will yield the highest energy storage per unit mass. This is one reason why carbon fiber is a material of interest. For a given design the stored energy is proportional to the hoop stress and the volume:

VIBRATION IN ENGINE : 

VIBRATION IN ENGINE An internal combustion engine produces power in the form of controlled explosions. These explosions produce powerful pulses of energy that cause the engine to vibrate in response. Engine designers do their best to make these forces cancel out to minimize vibrations. But, no matter how well the designer does his job, he cannot eliminate all inherent vibrations in an engine. Therefore we need to remember that it is perfectly normal for an IC (Internal combustion) engine to produce a characteristic vibration spectrum signature. Vibration analysis of IC engines then must focus on "variations" from the "normal" vibration signature.

CONTINUE : 

CONTINUE

LIMITATIONS OF ENGINE : 

LIMITATIONS OF ENGINE Small-scale energy conversion devices are being developed for a variety of applications. Notable are propulsion units for micro-aircraft vehicles (MAV). In spite of the fact that batteries have low energy density, batteries today power most of the micro aircrafts. Their low energy density significantly limits the aircraft performances. The high specific energy of hydrocarbon and hydrogen fuels, as compared to other energy storing means, like, batteries, elastic elements, flywheels, pneumatics, and fuel cells, appears to be an important advantage, and favors the internal-combustion-engine (ICE) as a candidate. In addition, the specific power (power per unit of mass) of the ICE is much higher than that of other candidates like fuel cells, photovoltaic, and battery units. Micro-engines are not simply smaller versions of full-size engines. Physical processes such as combustion, gas exchange, and heat transfer, are performed in regimes different from those occur in full-size engines. Consequently, engine design principles are different at a fundamental level, and have to be re-considered before they are applied to micro-engines. When a spark-ignition (Sl) cycle is considered, part of the energy that is released during combustion is used to heat-up the mixture in the quenching volume, and therefore the flame-zone temperature is lower and in some cases can theoretically fall below the self-sustained combustion temperature. The flame quenching thus seems to limit the minimum dimensions of a SI engine. This limit becomes irrelevant when a homogeneous-charge compression-ignition (HCCI) cycle is considered. In this case friction losses and charge leakage through the cylinder-piston gap become dominant, constrain the engine size, and impose minimum engine speed limits. In the present work a phenomenological model has been developed to consider the relevant processes inside the cylinder of a homogeneous-charge compression-ignition (HCCI) engine. The lower possible limits of scaling-down HCCI cycle engines are proposed. The present work postulates the inter-relationships between the pertinent parameters, and proposes the lower possible miniaturization limits of IC engines.

ADVANTAGES : 

ADVANTAGES There are other advantages to this scheme besides "no vibration".One is the option to 'cut' the channel in a manner other than a sine wave. For instance, one might want the piston to linger at the top of the compression stroke in order to allow for more complete burning of the fuel before using the energy on the downstroke. It might be possible to tweak some more efficiency out of internal combustion. The piston and piston rod are one solid unit eliminating "sideslap". It might also be possible to lay the engine sideways and mount two pistons on the same rod thereby creating a size minimized eight cylinder engine (all pistons running on the same sine track).

CONTINUE : 

CONTINUE The camshaft is easier to machine being now a plate mounted on top to the engine connected directly to the main shaft. (It can also double as the flywheel.) As the drum turns, raised metal on the plate activates the valves which can be accelerated to open and closed positions at any desired rate. This can be a very light engine. No counter weigths are required on the crankshaft for example. I estimate the size of a stock four cylinder engine to be about 12" x 12" x 18" which means you could probably pick it up and carry it to the basement for maintenance by yourself (... though I wouldn't personally advise it). An 8 cyl. engine mounted sideways wouldn't be much larger ~ 12" x 12" x 24" .

THANK YOU : 

THANK YOU GUIDED BY MR- ABHISHAKE PANDY SIR