Working Fluid

Transition value for Reynolds Number used in all tube elements.

For values of Reynolds Numbers within 5% of REYTRAN, the flow is assumed to be in transition. In the transition region a transition factor (between 0 and 1) is calculated as the ratio of (Reynolds Number minus 95% of REYTRAN) to (10% of REYTRAN). This transition factor is then used to linearly scale the values of friction factor, heat transfer coefficient, and adiabatic wall temperature between the fully laminar and the fully turbulent values.

For values of Reynolds Number above REYTRAN, turbulent flow values are used.

For values of Reynolds Number below REYTRAN, laminar flow values are used.

(Default value = 2300 providing a transition range from 2185 to 2415.)

Flag used to specify whether or not supersonic Mach numbers (Mach > 1.0) will be permitted in momentum chambers. Suggested input is either 0 or 2 depending on whether supersonic flow should be allowed.

< 2.0 Mach number to be limited to 1.0. (0-Supersonic Momentum Chambers Disallowed)

≥ 2.0 Supersonic Mach numbers are permitted. (2-Supersonic Momentum Chambers Allowed)

In inertial chambers, supersonic values are always permissible and ISUPER has no effect. (Default value = 0. Supersonic flow in momentum chambers not allowed)

Identifies working fluid(s).

0: Fluid 1 is Ideal Air; Fluid 2 is Steam (Default)

1-11: Not supported in standard FlowSimulator

12: Fluid 1 is Ideal Air; Fluid 2 is a Real Gas

13: Fluids 1 and 2 are distinct Real Gases

17: Fluid 1 is CEA air; Fluid 2 is a CEA fuel

18: Fluid 1 is Ideal Air; Fluid 2 is a CEA fuel

(Default value = 0.)

If PROPS is set to 17 or 18, FlowSimulator will look for either a fuel source component or a name list in the model database that identifies the type(s) of CEA fuel used. PROPS = 17 will use CEA definition of air properties for working fluid 1 instead of using the FlowSimulator definition of air (types 0, 12, 18).

Flag that specifies how FlowSimulator models should handle incompressible / compressible gas mixtures at chambers.

The values for the flag are:

0: All gas chambers - compressible

1: All gas chambers - incompressible

3: Treat chambers as compressible if at least one neighboring element is compressible

4: Treat chambers as incompressible if at least one neighboring element is incompressible

Chamber Temperature energy balance calculation procedure

0: T_Mixing_Default/ T_Mixing_Traditional→ Use 2nd order only for combustion models

2: T_Mixing_2nd_Order → Use new 2nd order T mixing, which works well when mixing different species