Card 6e - Thermal Coupling Request (forced convection)

The following NEARC options of the Card 6e model forced convection to hydraulic elements.

Parameters: L, N1S, N1F, N1D, N2S, N2D, HN1, KODE, EXP, P1, VX, VY, VZ

The N2 elements must be 2-node hydraulic elements. The forced convection conductance G is computed with:

where:

  • h is the computed forced convection heat transfer coefficient. KODE may be NEARC1, NEARC4, or NEARC12.
  • HN1 is a constant conductance multiplier.
  • KT is the conductance multiplier interpolated from optional Card 9 table EXP. EXP = blank defaults to KT = 1. The dependent variable on table EXP's TABTYPE Card must be COND.
  • ATC(N1) is the area of the overlap of N1 onto N2.

L

L is the code AREA (or 11)

The NEARx (recommended) options connect the N1 elements to the nearest of the N2 elements.

KODE = NEARC1

NEARC1 (or 3000) specifies how the forced convection heat transfer coefficient is computed.

If N1 is planar, h is calculated assuming it lies on the wall of a duct with fully developed duct flow.

If N1 is a beam element, h is calculated with free cylinder in cross flow correlations.

If N1 is a lump mass element, h is calculated with sphere in free flow correlations.

KODE = NEARC4

NEARC4 (or 3003) specifies how the forced convection heat transfer coefficient is computed using a flat plate in free stream correlation. The distance to the leading edge of the plate is the length of the flow path from the center of the hydraulic element N2 to the first upstream BLSTART element.

If there are no BLSTART elements specified, the leading edge is at the most upstream element.

N1 must be planar.

KODE = NEARC12

NEARC12 (or 3012) is similar to NEARC1, but the length of the boundary layer from the beginning of the duct is taken into account.

The boundary layer starts at the nearest upstream BLSTART element.

KODE = NEARC13

NEARC13 (or 3013) is similar to NEARC1, but 2-node beam elements are treated not as beams perpendicular to the flow, but as equivalent area shell elements parallel to the flow (i.e. as if they were on the pipe wall).

Code example

AREA BOARD 0 0 FLUID 0 1 NEARC1
$ FORCED CONVECTION CONDUCTANCES CALCULATED
$ FOR ELEMENTS OF BOARD