Find out what is the theoretical efficiency of a professional gasoline engine 5

Whether it is a gasoline engine or a diesel engine, the thermal efficiency can not exceed 45, the biggest reason is that the engine crank connecting rod mechanism and the work of the engine do not match, resulting in the piston thrust converted into crankshaft rotation when the energy input impedance is too large, when the piston thrust is the largest, the input resistance is infinite, and when the input resistance is the smallest, the piston thrust has been less than the maximum value of 1 4, and then the exhaust valve will be opened in advance, the waste of energy is actually very serious, It is impossible to achieve an energy conversion efficiency of 50 for a comprehensive evaluation of the crank linkage mechanism, and it is impossible for the thermal efficiency of the engine to exceed 45, which is the ceiling.

Generally reaching 30% is very good, you can consider atomizing gasoline to make gasoline burn more fully.

However, because gasoline is not subject to deflagration restrictions and diesel spontaneous combustion like diesel, the compression ratio of gasoline engines is lower than that of diesel engines, and the efficiency is lower.

In response to your question, I have a question: if the compression ratio is 1:10, how can I make the expansion ratio reach 1:?

20 or even 1:30?Is it possible that the exhaust pressure will reach 1 2 or 1 3 of the atmospheric pressure?

And if you draw the PV picture, you will find that if you increase the compression ratio, there is still a lot of room for improvement in the upper limit of the P value, but if you increase the expansion ratio, that is, the P value goes down, there is only one atmosphere of space in the space.

Your process like this is not a waiting cycle, go find a thermodynamics textbook and take a look.

Change the supercharge, (there is also an electronic fan supercharger) add 97 gasoline to increase the combustion rate,

Gasoline engine efficiency refers to the ratio of the heat equivalent of the effective power of the engine to the heat content of the fuel consumed per unit time, which is used to evaluate the economy of the engine as a heat engine. Gasoline engine efficiency range: Gasoline engines are between 80% and 90% efficient.

From the point of view of energy conversion, the conversion of electrical energy into kinetic energy has the highest efficiency, which can reach 100%, and is generated by a non-quasi-static process (frictional loss). At present, the efficiency of a gasoline engine is generally a quarter to a fifth of that of an electric motor, or twenty percent. If the mechanical efficiency is, the effective thermal efficiency of a gasoline engine is about 20% to 35%.

The effective thermal efficiency of a diesel engine is between 35% and 43%. Factors affecting the efficiency of a gasoline engine: air leakage between the combustion chamber and the cylinder of the diesel engine.

Changes in the volume of the combustion chamber, such as replacement of thickened cylinder gaskets, intake efficiency (air filter blockage, supercharger jamming, poor exhaust, valve cam wear, valve timing disorder, intake luck pipe leakage, poor cooling of diesel engine, heating intake air intake, etc.). ), injection and mixing efficiency. Carbon deposition in the injector, wear of the plunger of the oil pump of the wheel beam, pressure drop of the injector, inaccurate injection timing, etc.

1.Here is how efficiently a car starts a skidding machine:1.

2.Limited by the Carnot cycle, the theoretical maximum efficiency of gasoline engine is about 36%, and the efficiency of diesel engine is not high. 2.

From the point of view of energy conversion, the conversion of electrical energy into kinetic energy has the highest efficiency, up to 90%, and is affected by non-static processes (frictional losses); At present, the efficiency of gasoline engines is generally one-quarter to one-fifth of that of electric motors, that is, about 20%.

BAI for gasoline engines

Thermal efficiency refers to:

duThe mechanical work output of the engine and the DAO chemical energy produced by burning fuel.

ratio。That is, there is a specific amount of heat conversion into effective work. The thermal efficiency of current engines is generally only a little more than 30%.

Gasoline engine:

The gasolineengine is an engine that converts internal energy into kinetic energy using gasoline as fuel. Because gasoline is less viscous and evaporates quickly, gasoline can be injected into the cylinder with a gasoline injection system, and after compression reaches a certain temperature and pressure, it is ignited with a spark plug to make the gas expand to do work. The gasoline engine is characterized by high speed, simple structure, light weight, low cost, stable operation, and convenient use and maintenance.

How it works:

The engine is a machine that converts chemical energy into mechanical energy, and its conversion process is actually the process of the work cycle, simply put, it is through the combustion of fuel in the cylinder, generating kinetic energy, driving the reciprocating motion of the piston in the engine cylinder, thereby driving the connecting rod connected to the piston and the crank connected with the connecting rod, making a reciprocating circular motion around the center of the crankshaft, and outputting power.

Thermal efficiency is the ratio between the mechanical work output of the engine and the chemical energy produced by burning fuel. That is, how much zhi is evaluated

Heat is converted into effective work.

At present, the thermal efficiency of the engine is still very low from the numerical point of view, generally only a little more than 30%, improving thermal efficiency means improving the fuel economy of automobiles, and some new engine technologies that are emerging at present can be considered to improve thermal efficiency, such as TDI, TSI, TFSI, ECO-BOOST, etc.

The efficiency of a diesel engine is about 35, while the efficiency of a gasoline engine is about 27. It is equivalent to burning a pound of oil, the diesel engine has a pound to be wasted, and the gasoline engine has to have a pound to be wasted. When the engine is very powerful, of course, choose the diesel engine, choose the gasoline engine and you will die.

But why is there a gasoline engine with a small power? This brings us to the weight of the engine. Because diesel engines are much heavier than gasoline engines.

For the same three-horsepower engine, the gasoline engine is only about 20 pounds, while the diesel engine is nearly 100 pounds. If you put a three-horsepower diesel engine on a motorcycle, I'm afraid the engine will crush the car. The first consideration here is lightness.

So the dust wheel noisy choice of gasoline engine.

However, when installing a high-power engine on a heavy-duty truck with a load of 60 tons, the first consideration is fuel economy. Of course, I chose a diesel engine.

The answer is yours to choose.

The general efficiency of the gasoline engine: 26%--40%.

Efficiency of diesel engine: 34%--45%.

The average effective pressure refers to the effective work output of the engine per unit cylinder working volume, which is a very important parameter to measure the dynamic performance of the engine.

The effective fuel consumption rate is expressed in terms of the amount of fuel consumed per unit of effective power per hour, which is inversely proportional to the effective thermal efficiency.

The effective thermal efficiency is the ratio of the effective work actually cycled to the amount of heat expended to obtain this effective work.

Effective thermal efficiency and effective fuel consumption are effective indicators to measure the economic performance of an engine.