Determine the shape factor F1–4 for the geometrical configuration shown below.

Question

GIVEN

Geometrical configurations shown above

FIND

The shape factor F1–4

Answer 1

Let A5 =A1 + A2 and A6 = A3 + A4



Combining these equations A12 F12–34 = A3 F3–1 + A3 F3–2 + A4 F4–1 + A4 F4–2

By symmetry F1–4 = F2–3 = F4–1 = F3–2 and F3–1 = F1–3 = F2–4 = F4–2

Also A1 = A2 = A3 = A4 and A12 = 2A1

Therefore A12 F12–34 = 2A1 (F1–3 + F1–4)

Solving for F1–4 F1–4 = F12–34 – F1–3

The shape factors F1–3 and F12–34 can be determined