Determining characteristic curve of a four-stroke Diesel engine. - Calculating thermal efficiency of the engine. Apparatus. The experimental setup, shown in Fig . PDF | The simulation and computational development of modelling for the research is use the commercial Computational Fluid Dynamics (CFD) of GT- SUITE Explain simple engine operation. • Explain why gasoline is atomized in the small engine. • Describe four-stroke engine operation and explain the purpose of.
|Language:||English, Spanish, Arabic|
|Distribution:||Free* [*Registration needed]|
3. 48/60 – Four-stroke diesel engine. MAN Diesel & Turbo is the world's leading designer and manufacturer of low and medium speed engines. Our involvement . 2. Figure 2 Cutaway of a Four-Stroke Supercharged Diesel Engine 4. Figure 3 Cross Section of a V-type Four Stroke Diesel Engine. Nov 20, The four stroke cycle. ➊➋➌➍. Learning objective. ▫ To understand the mechanical working processes in a four stroke diesel engine.
At this time the Inlet valve is opened and the exhaust valves are closed. Suction will be created in the cylinder due to the movement of the piston downwards Bottom Dead centre the air will be drawn into the cylinder.
When the piston reaches the bottom dead centre BDC , the suction stroke will end.
Compression stroke Compression Stroke starts right after the suction stroke completes. Due to this, the air which is drawn into the cylinder will be compressed.
During this stroke, both the inlet and exhaust valves are closed. This volume is called clearance volume.
Now the fuel is injected into the cylinder by the high-pressure fuel injecter at the end of compression stroke. These two strokes i.
Expansion or power stroke During expansion stroke, both the inlet and exhaust valves remain closed. It is also called as working stroke as the linear movement of the piston is converted into the rotational movement by the cranks shaft. This is the first half of the cycle, until the the piston reaches it's highest point in the cylinder.
The next half of the cycle occurs when a spark plug ignites the fuel-air mixture when the piston is at it's peak, thereby causing the violent expansion of gases and pushing the piston back down to power the crankshaft and ultimately your vehicle.
This is sometimes also know as the "Power Stroke" The above two step repeat themselves again and again, and that's what makes a two stroke engined vehicle move.
Advantages of two strokes - Due to the existence of only two strokes, the "Power Stroke" occurs every half cycle. One in every two strokes produces power whereas in four stroke engines, only one in four strokes produces power.
This gives two stroke engines a significantly higher power-to-weight ratio than four strokes. Hence, even today chainsaws, lawnmowers and other small engined tools have a two stroke engine instead of a four stroke.
Disadvantages of two strokes - Very low fuel economy due to the combustion of exhaust gases and the escape of fuel. Since exhaust gases are re-compressed and hydrocarbons fuel are expelled from the exhaust, the exhaust is rich with carbon causing it's characteristic white colour and unusually high amounts of carbon monoxide.
Intake Stroke - Fuel-air mixture shown in blue below is sucked in to the piston when it as it's lowest point due the creation of low pressure. It is important to remember that unlike two stroke engines, four strokes have valves.