What is net power and net torque? What it the relationship between net power and net torque?
What is net power and net torque? What it the relationship between net power and net torque?
Net power: the effective power output by the engine’s
power output shaft that is measured when engine is equipped with all the
parts needed for actual operation conditions and is operated in the
regulated rotating speed in the engine laboratory table. It indicates
the amount and speed of the work done, i.e. the amount of work done in
unit time. The conventional unit of power is horsepower, and one
horsepower refers to work done by 75kg applied force that move one meter
in one second. To be unified with international unit, it is converted
into KW. 1 PS=0.7355 kW.
Net torque: the average torque output by the engine’s
power output shaft that is measured when engine is equipped with all the
parts needed for actual operation conditions and is operated in the
regulated rotating speed in the engine laboratory table. The
conventional unit of the torque is unit (N.m). When the power remains
the same, the torque is in inverse relation with the rotating speed of
the engine. The faster the rotating speed is, the smaller the torque is,
and vise versa.
Here, v means linear speed, and in the engine, crankshaft linear speed=
crankshaft angular speed(ω)×crankshaft radius (r), substitute into the
above formula: Power(p)= force(F) ×radius(r) ×angular speed(ω); And
force (F) ×radius(r)=torque
We can conclude that: power(P)= torque ×angular speed ω, so the power
of the engine can be calculated from the torque and rotating speed.
The unit of angular speed is radian/second, and in radian system, πmeans 180°.