What is the relationship between power and engine speed?
1 Answers
There is a significant relationship between engine output power and rotational speed. As the speed increases, the engine's power output also increases accordingly. However, beyond a certain speed, the power begins to decline. Therefore, the rotational speed at which the engine reaches its maximum power is called the maximum power speed. Generally, in automotive specifications, rotational speed is expressed in r/min (revolutions per minute). For example, a maximum power of 100ps/5000r/min means the engine produces its highest output of 100 horsepower at 5000 revolutions per minute. Related concepts are introduced as follows: 1. Power: The physical definition of power is the amount of work done by an object per unit time. For internal combustion engines, it can be understood as the amount of energy generated by fuel per unit time. Therefore, power is merely a physical quantity that describes how fast work is done. The higher the power, the more energy is generated per unit time, and often the higher the top speed of the vehicle. 2. Rotational Speed: In engines, rotational speed is defined as the number of revolutions the crankshaft makes per unit time, which is directly related to the vehicle's speed. The rotational speed undergoes torque multiplication and speed reduction through the entire drivetrain system, including the transmission and final drive, before it is ultimately reflected in the wheel speed. Therefore, the ratio between the engine speed and the wheel speed is the final drive ratio of the entire drivetrain system.
