Indicated Power Calculator:
Enter the values of number of cylinders, k, effective pressure, p(bar), Stroke length, L(m), piston area, A(m2) and engine speed, n(RPM) to determine the value of Indicated power, IP(W).
Indicated Power Formula:
Imagine a powerful engine driving a car. Indicated power (IP) represents the theoretical maximum power developed within the engine cylinders by the combustion process. It signifies the rate at which the engine converts the thermal energy from burning fuel into mechanical work.
Indicated power (IP) is a term commonly used in the context of internal combustion engines, particularly to describe the power derived directly from the pressure in the cylinders before any mechanical losses are accounted for through the engine’s components like the gearbox or drivetrain.
Fuel is burned within the engine cylinders, releasing thermal energy. This thermal energy expands the hot gases, pushing the piston down the cylinder (power stroke).
The force exerted by the expanding gases on the piston translates into mechanical work. The formula considers the engine’s design, combustion efficiency, and speed to estimate the theoretical maximum power generated by these processes.
Indicated power, IP(W) in watts is calculated by the product of 1.66, number of cylinders, k, effective pressure, p(bar) in bar, Stroke length, L(m) in metres, piston area, A(m2) in square metres and engine speed, n(RPM) in revolution per minute.
Indicated power, IP(W) = 1.66 * k * p(bar) * L(m) * A(m2) * n(RPM)
IP(W) = indicated power in watts, W.
k = number of cylinders.
p(bar) = effective pressure in bar.
L(m) = length in metres, m.
A(m2) = piston area in square metres, m2.
n(RPM) = engine speed in revolution per minute, RPM.
Indicated Power Calculation:
1. Calculating Indicated Power (IP)
Given:
Mean Effective Pressure p(bar) = 12 bar
Stroke Length L(m) = 0.1 m
Piston Area A(m2) = 0.05 m²
Engine Speed n(RPM) = 3000 RPM
Constant (k) = 1 (for simplification)
Indicated power, IP(W) = 1.66 * k * p(bar) * L(m) * A(m2) * n(RPM)
IP(W) = 1.66 * 1 * 12 * 0.1 * 0.05 * 3000
IP(W) = 9000W.
2. Finding Stroke Length (L):
Mean Effective Pressure p(bar) = 10 bar
Indicated power, IP(W) = 5000W
Piston Area A(m2) = 0.03 m²
Engine Speed n(RPM) = 2000 RPM
Constant (k) = 1 (for simplification)
Indicated power, IP(W) = 1.66 * k * p(bar) * L(m) * A(m2) * n(RPM)
L(m) = IP(W) / 1.66 * k * p(bar) * A(m2) * n(RPM)
L(m) = 5000 / 1.66 * 1 * 10 * 0.03 * 2000
L(m) = 5000 / 996
L(m) = 50m.