The heat exchanger is modelled as a volumetric energy source where the energy transfer between two fluid streams is based on an effectiveness, specified as a function of the mass flow rates.

\[Q_t = e \left(\dot{m}_1 , \dot{m}_2 \right) \left(T_2 - T_1\right) \dot{m}_1 C_p,\]


total heat source
effectiveness table
net mass flux entering heat exchanger [kg/s]
secondary mass flow rate [kg/s]
primary inlet temperature [K]
secondary inlet temperature [K]
specific heat capacity [J/kg/K]

The energy source is distributed across the cells according to:

\[Q_c = \frac{V_c |U_c| (T_c - T_{\ref})}{\sum(V_c |U_c| (T_c - T_{\ref}))},\]


energy source for cell
volume of the cell [m3]
local cell velocity [m/s]
local call temperature [K]
min or max(T) in cell zone depending on the sign of \(Q_t\) [K]

Optional entries:

  • primaryInletT : sets the primary inlet temperature. If not set, the flux-averaged temperature is used
  • targetQdot : the secondary inlet temperature is derived from a target heat rejection


The option is specified using:

    type            effectivenessHeatExchanger;
    selectionMode   cellZone;
    cellZone        porosity;

    secondaryMassFlowRate   1.0;
    secondaryInletT 336;
    faceZone        facesZoneInletOriented;
    outOfBounds     clamp;
    file            "effTable";

    // Optional
    // primaryInletT 293;
    // targetQdot   1500;

The two-dimensional effectiveness table is specified according to, e.g. for the table

  mfr2,1 mfr2,2 mfr2,3
mfr1,1 A B C
mfr1,2 D E F
mfr1,3 G H I

the equivalent entry becomes:

            (mfr2,1    A)
            (mfr2,2    B)
            (mfr2,3    C)
            (mfr2,1    D)
            (mfr2,2    E)
            (mfr2,3    F)
            (mfr2,1    G)
            (mfr2,2    H)
            (mfr2,3    I)

Further information


  • none

Source code


  • Introduced in version v3.0+
  • Previously known as:
    • heatExchangerSource : v2212
    • effectivenessHeatExchangerSource : v3.0+