Summation of View Factors
Because radiation leaving a surface is conserved, the sum of all view factors from a given surface, is unity:
For example, consider a case where two blobs with surfaces A and B are floating around in a cavity with surface C. All of the radiation that leaves A must either hit B or C, or if A is concave, it could hit A. 100% of the radiation leaving A is divided up among A, B, and C.
Confusion often arises when considering the radiation that arrives at a target surface. In that case, it generally does not make sense to sum view factors as view factor from A and view factor from B (above) are essentially different units. C may see 10% of A 's radiation and 50% of B 's radiation and 20% of C 's radiation, but without knowing how much each radiates, it does not even make sense to say that C receives 80% of the total radiation.
Read more about this topic: View Factor
Famous quotes containing the words summation, view and/or factors:
“He maintained that the case was lost or won by the time the final juror had been sworn in; his summation was set in his mind before the first witness was called. It was all in the orchestration, he claimed: in knowing how and where to pitch each and every particular argument; who to intimidate; who to trust, who to flatter and court; who to challenge; when to underplay and exactly when to let out all the stops.”
—Dorothy Uhnak (b. 1933)
“Now view yourself as I was, on the spot—
With a slight kind of engine. Do you see?
Like this . . . You wouldn’t hang me? I thought not.””
—Edwin Arlington Robinson (1869–1935)
“The goal of every culture is to decay through over-civilization; the factors of decadence,—luxury, scepticism, weariness and superstition,—are constant. The civilization of one epoch becomes the manure of the next.”
—Cyril Connolly (1903–1974)