engineering

Diesel Cycle Calculator

Calculate Diesel cycle thermal efficiency from compression ratio, cutoff ratio, and specific heat ratio

Diesel Cycle Calculator

η = 1 − (r_c^γ − 1) / (γ · r^(γ-1) · (r_c − 1))

Diesel: 14–25

V₃/V₂, typical 1.5–4

Thermal Efficiency

63.16%

η = 0.6316

State Points

StateT (K)P (kPa)
1 (BDC, start)300.0100.0
2 (TDC, compressed)953.35719.8
3 (end of injection)1906.65719.8
4 (BDC, expanded)791.7263.9

Energy Summary (kJ/kg)

q_in

958.0

W_net

605.0

q_out

352.9

Comparison with Otto (same r)

Otto η = 68.53%
Diesel η = 63.16%
Diesel is less efficient than Otto at same r

How to Use This Calculator

1

Enter your input values

Fill in all required input fields for the Diesel Cycle Calculator. Most fields include unit selectors so you can work in your preferred unit system.

2

Review your inputs

Double-check that all values are correct and that you have selected the right units for each field. Incorrect units are the most common source of calculation errors.

3

Read the results

The Diesel Cycle Calculator instantly computes the output and displays results with units. All calculations happen in your browser — no loading time and no data sent to a server.

Formula Reference

Diesel Cycle Calculator Formula

See calculator inputs for the governing equation

Variables: All variables and their units are labeled in the calculator interface above.

When to Use This Calculator

  • Use the Diesel Cycle Calculator when solving homework or exam problems that require quick numerical verification of your hand calculations.
  • Use it during the design phase to rapidly iterate on parameters before running detailed finite element simulations.
  • Use it when reviewing a colleague's calculation or checking a vendor's data sheet for plausibility.
  • Use it to generate reference data for a technical report or presentation without manual computation.

Related Calculators