Ideal Engine Cycle Efficiency Calculator
Compute the efficiency of Carnot, Otto, Diesel, or Brayton cycles by entering temperatures and cycle-specific parameters
Calculator
Select a cycle type, input the parameters, and choose units for temperature. The efficiency will be calculated and displayed in a table.
About the Ideal Engine Cycle Efficiency Calculator
The Ideal Engine Cycle Efficiency Calculator helps you compute the theoretical efficiency (η) of popular engine cycles including Carnot, Otto, Diesel, and Brayton cycles. By entering relevant parameters such as temperatures, compression ratio, and cutoff ratio, this calculator determines the ideal efficiency according to thermodynamic principles.
Supported Engine Cycles
- Carnot Cycle: Maximum possible efficiency between two temperatures.
- Otto Cycle: Ideal efficiency for spark-ignition engines, depends on compression ratio.
- Diesel Cycle: Efficiency for compression-ignition engines, depends on compression and cutoff ratios.
- Brayton Cycle: Efficiency of ideal gas turbine cycles, depends on pressure ratio.
Key Formulas Used
- Carnot: η = 1 - TC/TH
- Otto: η = 1 - 1/rγ-1, r = compression ratio, γ ≈ 1.4 for air
- Diesel: η = 1 - (1/rγ-1) × ((rcγ - 1)/(γ × (rc - 1)))
- Brayton: η = 1 - r(1-γ)/γ, r = pressure ratio
How to Use the Calculator
- Select the desired engine cycle from the dropdown menu.
- Enter the high (TH) and low (TC) temperatures. Choose units (K or °C).
- For Otto and Diesel cycles, enter the compression ratio. For Diesel, also enter the cutoff ratio.
- The calculator will display the ideal efficiency as a percentage in the results table.
Applications of Engine Cycle Efficiency Calculations
- Estimate theoretical performance of heat engines and turbines.
- Compare different engine cycles for energy efficiency.
- Support research, teaching, and thermodynamics problem-solving.
- Analyze effects of temperature and compression ratios on engine efficiency.