Enter the fin heat transfer (J) and the ideal fin heat transfer (J) into the calculator to determine the Fin Efficiency. 

Fin Efficiency Formula

The following formula is used to calculate the Fin Efficiency. 

Ef = Qf / Qif *100

  • Where Ef is the Fin Efficiency (%)
  • Qf is the fin heat transfer (J) 
  • Qi is the ideal fin heat transfer (J) 

How to Calculate Fin Efficiency?

The following two example problems outline how to calculate the Fin Efficiency.

Example Problem #1:

  1. First, determine the fin heat transfer (J). In this example, the fin heat transfer (J) is given as 40.
  2. Next, determine the ideal fin heat transfer (J). For this problem, the ideal fin heat transfer (J) is given as 50.
  3. Finally, calculate the Fin Efficiency using the equation above: 

Ef = Qf / Qif *100

Inserting the values from above and solving the equation: 

Ef = 40 / 50 *100 = 80 (%)


Example Problem #2: 

Using the same process as above, first define the variables required by the formula. In this case, these values are:

fin heat transfer (J) = 70

ideal fin heat transfer (J) = 90

Entering these values yields:

Ef = 70/ 90 *100 = 77.77 (%)