Enter the number of cylinders, the effective pressure (bar), RPM, piston area (m^2), and the stroke length (m) into the calculator to determine the Indicated Power. 

Indicated Power Formula

The following formula is used to calculate the Indicated Power.

IP = 100 * k * p * L * A *n / 60

  • Where IP is the Indicated Power (kW)
  • k is the number of cylinders 
  • p is the effective pressure (bar) 
  • L is the stroke length (m) 
  • A is the piston area (m^2)
  • n is the rotational speed (RPM)

How to Calculate Indicated Power?

The following example problems outline how to calculate Indicated Power.

Example Problem #1

  1. First, determine the number of cylinders. In this example, the number of cylinders is determined to be 2.
  2. Next, determine the effective pressure (bar). For this problem, the effective pressure (bar) is measured to be 41 .
  3. Next, determine the stroke length (m). In this case, the stroke length (m) is found to be 4.
  4. Next, determine the piston area. In this case, the area is .25.
  5. Next, determine the RPM. This is given as 30.
  6. Finally, calculate the Indicated Power using the formula above: 

IP = 100 * k * p * L * A *n / 60

Inserting the values from above and solving yields: 

IP = 100 * 2* 41 * 4 * .25 *30 / 60 = 4100 (kW)


Example Problem #2

Using the same method as above, determine the variables required by the formula. For this example problem, these are:

number of cylinders = 2

effective pressure (bar) = 8

stroke length (m) = .09

area (m^2) = .67

RPM = 100

Enter these given values into the calculator or above yields: 

IP = 100 * 2* 8 * .09 * .67 * 100 / 60 = 160.8 (kW)