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Carnot Efficiency Calculator

Calculate Ideal Gas Law (PV=nRT), Carnot efficiency, heat transfer Q = mcΔT, entropy ΔS, enthalpy, and thermal resistance for carnot efficiency.

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Input Thermodynamic Parameters

Enter temperature T, mass m, specific heat c, or pressure P.

Calculated Heat Energy (Q)

418.40 kJ
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Carnot Efficiency Bound

The maximum theoretical efficiency of any heat engine Operating between hot reservoir T_H and cold reservoir T_C is η_Carnot = 1 - (T_C / T_H) in Kelvin.

Calculation Methodology & Details

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Formula

Heat Energy Transfer: Q = m × c × ΔT Ideal Gas Law: P × V = n × R × T Carnot Efficiency: η = 1 - (T_cold / T_hot) Gibbs Free Energy: ΔG = ΔH - T × ΔS LMTD Heat Exchanger: ΔT_lm = (ΔT₁ - ΔT₂) / ln(ΔT₁ / ΔT₂)

Applies 1st and 2nd Laws of Thermodynamics, kinetic theory of gases, Van der Waals real gas state equations, and Rankine/Otto heat engine power cycles.

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Important Disclaimer

Temperatures used in thermodynamic ratios (T_C / T_H, gas law PV=nRT) must always be in absolute units Kelvin (K = °C + 273.15).

How to Calculate Step-by-Step

Follow these steps to complete the calculation:

1

Step 1

Enter substance mass m (kg) or gas volume V (m³ / Liters).

2

Step 2

Input initial and final temperatures T1 and T2 (°C or K) or specific heat capacity c.

3

Step 3

View heat energy transfer Q (Joules or BTU), Carnot cycle thermal efficiency (%), entropy change ΔS (J/K), or LMTD heat exchanger rating.

Detailed Insights & Expert Guide

ℹ️ About this Calculation

The Carnot Efficiency Calculator solves thermodynamic state variables (PV=nRT), sensible and latent heat transfer, Carnot/Rankine/Otto cycle efficiency, heat exchanger LMTD, and Gibbs free energy spontaneous reaction criteria.

Variable Glossary

Input

Specific Heat (c)

Amount of heat energy required to raise the temperature of 1 kg of a substance by 1 °C (J/kg·K).

Parameter

Entropy (S)

Thermodynamic state function measuring molecular disorder and unavailable thermal energy (J/K).

FAQ

What is the difference between Sensible and Latent Heat?
Sensible heat causes a measurable change in temperature (Q = mcΔT) without phase change. Latent heat causes phase change (melting/boiling, Q = mL) at constant temperature.
What is LMTD in Heat Exchangers?
Log Mean Temperature Difference (LMTD) represents the effective temperature driving force for heat transfer in heat exchangers (counter-flow or parallel flow): Q = U × A × LMTD.
What is Gibbs Free Energy (ΔG)?
Gibbs Free Energy ΔG = ΔH - TΔS determines reaction spontaneity. If ΔG < 0, the reaction is exergonic and spontaneous; if ΔG > 0, it requires external energy input.