Card 6b - Solar View Factor Request

This optional card specifies the parameters and options for solar view factor calculations.

Parameters: L, N1, THETAS, PHIS, TIME, PSUN, REVN1

L

L is the type of solar view factor calculation request.

  • L = SOLS1 (or 7) calculates a single solar view factor with shadowing for element or group N1.
  • L = SOLN1 (or 8) is the same as L = SOLS1 with no shadowing.
  • L = SOLSALL (or 9) calculates solar view factors with shadowing for all elements starting with element N1, in the order the Card 5 elements occur. For solar view factors to all elements, N1 should be 0.
  • L = SOLNALL (or 10) is the same as L = SOLSALL with no shadowing.

N1

N1 may be an element number or a group name.

THETAS

THETAS is the angle in degrees the sun vector makes with the Z axis. The sun vector is defined as a unit vector at the origin pointing towards the sun.

PHIS

PHIS is the angle in degrees the projection of the sun vector on the XY plane makes with the X axis (CCW is positive).

TIME

TIME defines the time when a solar view factor occurs. TIME can be blank, or the flag CONSTANT for constant heat loads. TIME = blank defaults to CONSTANT.

PSUN

PSUN is optional, it defines the collimated solar spectrum radiative source's (sun's) power output per unit area for the view factor request. PSUN overrides the Card 2a default PSUN value.

PSUN = 0 or blank, the Card 2a PSUN value will be used.

PSUN = Tn or PSUN =-n, where n is a table number (e.g. T10 or -10), and n is a table whose dependent variable is QNODE, and TIME = CONSTANT, then the PSUN value will be interpolated from the table n by the Analyzer during run time.

REVN1

REVN1 is applicable for L = SOLS1 or SOLN1, otherwise it must be blank or 0. REVN1 may be 0 or an element or a group name, and the reverse sides of the REVN1 element(s) are added to the N1 elements.

Code example


 SOLS1 3 45 38 12     $ SOLAR VF WITH SHADOWING FOR EL. 3 TIME = 12
 SOLSALL 0 45 38 12   $ SOLAR VF'S FOR ALL ELEMENTS, TIME = 12

Notes

The sun is modeled as a collimated point source at a distance of 1.E6 from the origin, and pointing towards it.

Solar view factor calculations to the space elements are not performed, and space elements do not cause shadowing. For elements to be considered non–shadowing space elements, their nodes must be at distances greater than 1.E6, to prevent them from shadowing the sun. For more information, see Card 5d - Space Element Generation.

If duplicate solar view factor requests are present to the same element, the first one takes precedence.