What is the Engine Thermo Lab multi-solver?

Engine Thermo Lab is a guided workflow that chains 2 individual PolySim solvers into one end-to-end analysis, piping each result into the next step.

Yes. Every step runs entirely in your browser using real numerics — no install, no account, no cloud cost. Custom or private solver packs are available as a paid service.

Fluids & Energy Pack · Multi-Solver

Engine Thermo Lab

Cycle & efficiency. This multi-solver chains 2 solvers into a single guided workflow — run each step in order and carry the result forward.

Workflow steps

otto-cycle
→carnot-cycle

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Otto Cycle

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Otto Cycle (Engine)Live

gasoline engine efficiency

Controls

Presets

Compression ratio

Heat capacity ratio γ

The Otto cycle idealizes a gasoline engine: adiabatic compression, constant-volume combustion, adiabatic expansion (the power stroke), and exhaust. Its efficiency, η = 1 − 1/r^(γ−1), depends only on the compression ratio. Higher compression means more efficiency — until the fuel pre-ignites and knocks, which is why octane rating matters.

▶ Run in Python

Data Inspector

Efficiency58.5%

Compression ratio9:1

γ1.40

Governing equation

η = 1 - \frac{1}{r ^{γ - 1}} = 1 - \frac{1}{9 ^{1.40 - 1}} = 58.5%

Reading this result: Efficiency (58%) depends only on the 9:1 compression ratio and γ, not on how much fuel you burn — adding heat gives more power at the same efficiency ceiling.

Runs locally in your browser — free forever. Scale to the cloud when reality gets heavy.

↓

Carnot Cycle

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Carnot CycleLive

the ideal heat engine

Controls

Presets

Hot reservoir Tₕ (K)

Cold reservoir Tc (K)

Expansion ratio

The Carnot cycle — two isothermal and two adiabatic steps — is the most efficient possible heat engine between two temperatures. Its efficiency depends only on the reservoir temperatures: η = 1 − Tc/Th. No real engine can beat it, which is why raising the hot temperature or lowering the cold one is the only path to higher efficiency.

▶ Run in Python

Data Inspector

Efficiency50.0%

Tₕ / Tc2.00

Carnot limit50.0%

Governing equation

η = 1 - \frac{T _{c}}{T _{h}} = 1 - \frac{300}{600} = 0.500

Reading this result: Efficiency here is 50.0% and is fixed by the temperature ratio alone — widening the expansion ratio enlarges the enclosed work loop but can never push past the 50.0% Carnot ceiling, and each kelvin removed from the cold side buys a bit more than each kelvin added to the hot side.

Runs locally in your browser — free forever. Scale to the cloud when reality gets heavy.

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Frequently asked questions

What is the Engine Thermo Lab multi-solver?: Engine Thermo Lab is a guided workflow that chains 2 individual PolySim solvers into one end-to-end analysis, piping each result into the next step.
Is it free to use?: Yes. Every step runs entirely in your browser using real numerics — no install, no account, no cloud cost. Custom or private solver packs are available as a paid service.