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Fluids

Fluid catalog, state-point calculator, backends, range explorer, and heat-transfer numbers.

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Fluids

The fluid library is built around one state-point workflow: choose a fluid, define temperature and pressure, calculate properties, then export or explore ranges when needed.

Catalog page

Open Fluids to search gases, liquids, refrigerants, oils, fuels, and reviewed local engineering models. The catalog shows source quality where relevant and links each row to the calculator.

Use the catalog page for selection. Use the calculator page for calculations.

State-point calculator

Open Fluid calculator. The calculator supports:

  • Temperature and pressure input with common SI and Imperial units.
  • Output unit system selection.
  • Backend selection where applicable.
  • Relative humidity for air.
  • Optional flow inputs for Reynolds, Peclet, Nusselt, Grashof, and Rayleigh numbers.
  • Saturation and P-h modes for supported fluids.

Range explorer

The range explorer belongs to the fluid calculation page. Use it when a property must be reviewed over temperature, pressure, or a temperature-pressure grid.

Multi-fluid comparisons support temperature sweeps. Use a single fluid for a pressure sweep or temperature-pressure grid. Comparison tables identify each fluid and show applicable warnings. A phase-boundary error in any selected fluid stops the comparison; reduce the range or choose a different state point.

Changing inputs clears the previous calculation and disables its exports. Calculate or generate the range again to obtain results for the new inputs. Exports use the inputs belonging to the completed result.

Range explorer outputs can be exported as:

  • Table
  • CSV
  • PDF report
  • Chart inside the report when the range is valid

Air and humidity

Air is handled as one practical engineering fluid. Dry air is the default case with relative humidity at 0 percent. Enter relative humidity when moist-air density and psychrometric helper values are needed.

Backends

The backend selection should normally stay on auto. It chooses the best approved backend for the selected fluid. Explicit backend selection is useful for debugging, comparison, or checking fallback behavior.

Common backend labels:

  • CoolProp
  • Thermo / ChEDL
  • Chemicals / ChEDL
  • Cantera
  • Local reviewed model

Result checks

Before using a calculated result:

  • Check phase and warnings.
  • Check source quality.
  • Check validity range.
  • Confirm the output unit system.
  • Use evidence-pack PDF when the result must be stored with inputs and metadata.