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ENES

Real-Gas Properties

Run a capability-checked HEOS, Peng–Robinson or SRK property calculation for selected pure gases at an explicitly declared temperature and absolute pressure. The pinned engine loads only when you request it and does not send the state to a service.

FreeNo sign-upPrivate — runs in your browser, nothing is uploaded

Loads the pinned CoolProp 8.0.0 browser engine only when requested. Inputs stay on this device.

This real-fluid view admits 22 of the 29 catalog gases. The pinned engine has no finite HEOS state for acetylene, nitrogen trifluoride, hexafluoropropylene, silane, germane, phosphine, and diborane, so none is silently replaced with an ideal-gas value here. They remain available for ideal-reference conversion and batch mass/amount conversion.

Choose a material, model and absolute state, then run a capability-checked calculation.

Quick answer

A real-gas property is model- and state-dependent. This calculator labels the selected model and returns no substitute number when the requested material, output or state is unavailable from the pinned runtime.

Formula & method

EOS(T, P, material, model) → density, Z, h, s, u, Cp, Cv
  • T — absolute temperature
  • P — absolute pressure
  • Z — compressibility factor

HEOS and cubic-EOS outputs are model predictions, not a substitute for a certified material data sheet or process-safety review.

Examples

Example 1: Nitrogen at ambient pressure
Input
N₂, HEOS, 298.15 K, 101,325 Pa(a)
Result
Density, Z and supported mass-specific properties
Why
The runtime verifies its pinned files and version before evaluating the named state.
Example 2: CO₂ cubic comparison
Input
CO₂, PR or SRK, 320 K, 2 MPa(a)
Result
Density and Z when admitted
Why
Cubic model results are presented as model predictions rather than measured truth.
Example 3: Unsupported state
Input
Any state or property outside the admitted matrix
Result
Explicit unavailable status
Why
The calculator never falls back to an ideal-gas value for a real-fluid request.

When to use this tool

  • Comparing the supported pure-gas models at a declared state.
  • Checking whether real-gas compressibility materially differs from one.
  • Obtaining a reproducible local model result before engineering review.

Common mistakes

  • Entering gauge pressure as absolute pressure.
  • Treating a cubic-EOS prediction as a calibration certificate.
  • Using a phase-sensitive result when the requested phase has not been admitted.

Assumptions

What the result takes for granted:

  • The state is a pure material, not a composition or a cylinder inventory.
  • The selected model is only used where the local capability matrix admits it.
  • The engine files and version are verified locally before calculation.

Limitations

Where this tool stops — and what to use instead:

  • This is not a phase-envelope, flash, regulator, relief or process-design tool.
  • An unavailable result deliberately contains no fabricated numerical fallback.
  • Independent scientific validation remains distinct from an engine regression check.

Frequently asked questions

Why does the first calculation take longer?

The 9.2 MB pinned WebAssembly runtime is fetched and hash-verified only when a real-fluid calculation is requested.

Why can a result be unavailable?

The input may be outside the admitted material/model/output/state scope or the engine may return a non-finite result. Showing no number is safer than guessing.

Are PR and SRK measurements?

No. They are equation-of-state model predictions and can differ from each other and from measured data.

Sources & references

External references open in a new tab. We are independent and not affiliated with these organizations.

  • ✓ Free to use
  • ✓ No sign-up required
  • ✓ Runs entirely in your browser — nothing is uploaded.
  • ✓ Formula and method shown above
Last updated: How we calculateReport a correctionDisclaimer

Provided “as is” for general information only — results may be inaccurate, so verify before you rely on them. No warranty; use at your own risk.

Built and reviewed by HIFreeTools against the formula shown above and any authoritative references cited on this page. See our methodology and editorial standards.

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