What does automotive thermal efficiency refer to?

[EmiliaAnn]

Engine thermal efficiency is one of the indicators for evaluating engine performance. The higher the engine's thermal efficiency, the better the fuel economy, performance, and emissions will be. The introduction to engine thermal efficiency is as follows: Thermal efficiency energy: If no energy is consumed beyond the body's basal metabolism, then for an engine, it means the power generated by fuel combustion is only used for its own operation without any external power output. From this perspective, it can be considered as having 0% thermal efficiency. Gasoline engine working principle: An engine is a machine that converts chemical energy into mechanical energy. Its conversion process is essentially the working cycle. Simply put, it involves burning fuel in the cylinders to generate kinetic energy, which drives the pistons inside the engine cylinders to move back and forth. This movement then drives the connecting rods attached to the pistons and the crankshaft connected to the rods, causing them to perform reciprocating circular motions around the crankshaft center, thereby outputting power.