Relative Efficiency Calculator

✖Indicated Thermal Efficiency is given by the ratio of indicated power generated by the engine to the power generated by the combustion of the fuel.ⓘ Indicated Thermal Efficiency [IDE]			+10% -10%
✖Air Standard Efficiency (in %) is the efficiency of the engine using air as the working medium. This efficiency is often called ideal efficiency.ⓘ Air Standard Efficiency [η_a]			+10% -10%

✖The Relative Efficiency of an I.C. engine is the ratio of indicated thermal efficiency to the thermal efficiency of a theoretically reversible cycle.ⓘ Relative Efficiency [η_r]

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Relative Efficiency Solution

STEP 0: Pre-Calculation Summary

Formula Used

Relative Efficiency = (Indicated Thermal Efficiency/Air Standard Efficiency)*100
η_r = (IDE/η_a)*100
This formula uses 3 Variables

Variables Used

Relative Efficiency - The Relative Efficiency of an I.C. engine is the ratio of indicated thermal efficiency to the thermal efficiency of a theoretically reversible cycle.
Indicated Thermal Efficiency - Indicated Thermal Efficiency is given by the ratio of indicated power generated by the engine to the power generated by the combustion of the fuel.
Air Standard Efficiency - Air Standard Efficiency (in %) is the efficiency of the engine using air as the working medium. This efficiency is often called ideal efficiency.

STEP 1: Convert Input(s) to Base Unit

Indicated Thermal Efficiency: 0.42 --> No Conversion Required
Air Standard Efficiency: 5 --> No Conversion Required

STEP 2: Evaluate Formula

Substituting Input Values in Formula

η_r = (IDE/η_a)*100 --> (0.42/5)*100

Evaluating ... ...

η_r = 8.4

STEP 3: Convert Result to Output's Unit

8.4 --> No Conversion Required

FINAL ANSWER

8.4 <-- Relative Efficiency

(Calculation completed in 00.020 seconds)

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Created by Aditya Prakash Gautam

Indian Institute of Technology (IIT (ISM) ), Dhanbad, Jharkhand

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National Institute Of Technology (NIT), Hamirpur

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Brake specific fuel consumption

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Brake Power given Mechanical Efficiency

LaTeX Go Brake Power = (Mechanical Efficiency/100)*Indicated Power

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Brake Power given Mean Effective Pressure

LaTeX Go Brake Power = (Brake Mean Effective Pressure*Stroke Length*Area of Cross Section*(Engine Speed))

Indicated Power given Mechanical Efficiency

LaTeX Go Indicated Power = Brake Power/(Mechanical Efficiency/100)

Brake Power given Mechanical Efficiency

LaTeX Go Brake Power = (Mechanical Efficiency/100)*Indicated Power

Mechanical Efficiency of IC engine

LaTeX Go Mechanical Efficiency = (Brake Power/Indicated Power)*100

Relative Efficiency Formula

LaTeX Go

Relative Efficiency = (Indicated Thermal Efficiency/Air Standard Efficiency)*100
η_r = (IDE/η_a)*100

What is relative efficiency of an IC engine ?

Relative efficiency or 'Efficiency Ratio' is the ratio of indicated thermal efficiency and the air standard efficiency of an IC engine or the ratio of the actual efficiency obtained from an engine to the theoretical efficiency of the engine cycle.

How to Calculate Relative Efficiency?

Relative Efficiency calculator uses Relative Efficiency = (Indicated Thermal Efficiency/Air Standard Efficiency)*100 to calculate the Relative Efficiency, The Relative Efficiency formula is defined as the ratio of indicated thermal efficiency and the air standard efficiency of an IC engine. Relative Efficiency is denoted by η_r symbol.

How to calculate Relative Efficiency using this online calculator? To use this online calculator for Relative Efficiency, enter Indicated Thermal Efficiency (IDE) & Air Standard Efficiency (η_a) and hit the calculate button. Here is how the Relative Efficiency calculation can be explained with given input values -> 0.84 = (0.42/5)*100.

FAQ

What is Relative Efficiency?

The Relative Efficiency formula is defined as the ratio of indicated thermal efficiency and the air standard efficiency of an IC engine and is represented as η_r = (IDE/η_a)*100 or Relative Efficiency = (Indicated Thermal Efficiency/Air Standard Efficiency)*100. Indicated Thermal Efficiency is given by the ratio of indicated power generated by the engine to the power generated by the combustion of the fuel & Air Standard Efficiency (in %) is the efficiency of the engine using air as the working medium. This efficiency is often called ideal efficiency.

How to calculate Relative Efficiency?

The Relative Efficiency formula is defined as the ratio of indicated thermal efficiency and the air standard efficiency of an IC engine is calculated using Relative Efficiency = (Indicated Thermal Efficiency/Air Standard Efficiency)*100. To calculate Relative Efficiency, you need Indicated Thermal Efficiency (IDE) & Air Standard Efficiency (η_a). With our tool, you need to enter the respective value for Indicated Thermal Efficiency & Air Standard Efficiency and hit the calculate button. You can also select the units (if any) for Input(s) and the Output as well.

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