indicated horsepower
Quick Summary
Indicated horsepower (ihp) is a measure of the power developed within the cylinders of an engine. It is calculated using the average pressure of the working fluid, the piston's area, its stroke length, and the number of working strokes per minute.1
This is distinct from brake horsepower (bhp), which measures the engine's power at the output shaft after accounting for internal friction losses. Indicated horsepower represents the theoretical power generated before these mechanical losses occur.23
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- horsepower
…sizes, is often expressed as indicated horsepower, which is determined from the pressure in the cylinders. Brake or shaft horsepower is less than indicated horsepower by the amount of power lost to friction within the engine itself, which may amount to 10 percent or more of the indicated horsepower. Electric…
Read More…sizes, is often expressed as indicated horsepower, which is determined from the pressure in the cylinders. Brake or shaft horsepower is less than indicated horsepower by the amount of power lost to friction within the engine itself, which may amount to 10 percent or more of the indicated horsepower. Electric…
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gasoline enginePerformanceThis quantity is the indicated horsepower of the engine, so called from an instrument known as the engine indicator, which is used to measure the pressure on the piston and thus calculate the power developed in the cylinder.
Read MoreThis quantity is the indicated horsepower of the engine, so called from an instrument known as the engine indicator, which is used to measure the pressure on the piston and thus calculate the power developed in the cylinder.
Read More