Diesel Engine Thermal Efficiency

The thermal efficiency of a conventional steam engine is 4%-8%, the thermal efficiency of a gasoline engine is in the range of 25%-35%, a diesel engine can achieve a thermal efficiency of 35%-45%, and the thermal efficiency of a jet engine is in the range of 50%-60%.

Diesel engines and gasoline engines, compared to the same power, the diesel engine torque, the maximum power when the rotational speed is low. The greater the torque output the greater the carrying capacity, the better the acceleration performance, the stronger the climbing force, which also shows that the diesel engine than the gasoline engine has the strength.

Torque, like power, is one of the main indices of an automobile engine, which is reflected in the performance of the car, including acceleration, hill climbing ability. It is precisely defined as the cross product (M) of the bit vector (L) and the force (F), which in physics means the force that makes an object rotate multiplied by the distance to the rotating shaft, and it can indicate the magnitude of the force output from the engine (because the crankshaft in the engine has a certain radius).

In layman's terms, torque is an important measure of how good a car's engine is, and the amount of torque in a car is directly proportional to the engine's power.

Expanded:

Diesel engines have the advantage of being a good engine. p>The advantages of a diesel engine are high torque and good economy. Each working cycle of a diesel engine also undergoes four strokes: intake, compression, work, and exhaust. However, because the fuel used in diesel engines is diesel, which is more viscous than gasoline and is less likely to evaporate, while its auto-ignition temperature is lower than that of gasoline, the formation of combustible mixtures and ignition methods are different from those of gasoline engines.

The main difference is that the mixture in the cylinder of a diesel engine is compression ignition, not ignition. Diesel engine work into the cylinder is air, the air in the cylinder compressed to the end of the temperature up to 500-700 ℃, the pressure up to 40-50 atmospheric pressure.

Piston close to the upper stop, the engine on the high-pressure pump to high-pressure diesel fuel injection into the cylinder, diesel fuel to form fine oil particles, and high pressure and high temperature air mixture, diesel fuel mixture combustion on its own, violently expanding, resulting in an explosive force, pushing the piston down to do work, at this time, the temperature can reach 1900-2000 ℃, the pressure can be up to 60-100 atmospheres, resulting in a great torque, so the Diesel engines are widely used in large diesel vehicles.

Reference: