Heat Engine Efficiency Calculator (η=W/Qh)
Compute real heat engine efficiency η = W/Qh: given any two of heat input, heat rejection and work output, solve the third and the efficiency.
Key points
Heat Engine Efficiency Calculator (η=W/Qh): Compute real heat engine efficiency η = W/Qh: given any two of heat input, heat rejection and work output, solve the third and the efficiency. Formula: η = W / Qh = (Qh − Qc) / Qh. Enter parameters on the DD-CAT IDE online tool page to get results instantly, with a calculation-model diagram that updates with the inputs. Engine efficiency η = W/Qh = (Qh − Qc)/Qh is always less than 1; real efficiency is far below the Carnot efficiency of the same temperature range. Energy conservation: heat input Qh = work output W + heat rejection Qc.
Inputs
η = W / Qh = (Qh − Qc) / QhCalculation model (updates with parameters)
| Engine efficiency η | 30% | η = W / Qh |
| Heat input Qh | 1 kJJ | |
| Work output W | 300 JJ | |
| Heat rejection Qc | 700 JJ | Qc = Qh − W |
Engineering notes
- Engine efficiency η = W/Qh = (Qh − Qc)/Qh is always less than 1; real efficiency is far below the Carnot efficiency of the same temperature range.
- Energy conservation: heat input Qh = work output W + heat rejection Qc.
- Gasoline engines ≈ 25–35%, diesel ≈ 35–45%, combined gas-steam cycles can exceed 60%.
FAQ
- What is Heat Engine Efficiency Calculator (η=W/Qh) for?
- Compute real heat engine efficiency η = W/Qh: given any two of heat input, heat rejection and work output, solve the third and the efficiency.
- What is the formula for Heat Engine Efficiency Calculator (η=W/Qh)?
- Core formula: η = W / Qh = (Qh − Qc) / Qh. The tool returns results instantly using this formula and the selected parameters.
- What engineering notes should I keep in mind when using Heat Engine Efficiency Calculator (η=W/Qh)?
- Engine efficiency η = W/Qh = (Qh − Qc)/Qh is always less than 1; real efficiency is far below the Carnot efficiency of the same temperature range. Energy conservation: heat input Qh = work output W + heat rejection Qc. Gasoline engines ≈ 25–35%, diesel ≈ 35–45%, combined gas-steam cycles can exceed 60%.