Question

Determine F12 and F21 for the following configurations: (a) A long semicircular duct with diameter of 0.1 meters: (b) A hemisphere-disk arrangement, with hemisphere diameter of 0.1 meters:

Answer 1

long duct: 1.0 and 0.424

Hemisphere 1.0 ; 0.125; 0.5

Step-by-step explanation:

For a long duct:

By inspection,
`F_(12) = 1.0`

Calculating by reciprocity,
`F_(21) = (A_(1) )/(A_(2)F_(12) ) = (2RL)/((3)/(4)*2\pi RL )* 1.0\\ = 0.424`

Hemisphere:

By reciprocity gives = 0.125

using the summation rule:
`F_(21) + F_(22) + F_(23) = 1`

However, because this is a hemisphere, the value will be= 0.5 * 1

= 0.5