Based on q = hΔT. | Based on ΔT = f{q}. | – |
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U = 1/(1/h1{ΔT1} + t/k + 1/h2{ΔT2) | ΔTtotal = ΔT1{q} + ΔTwall{q} + ΔT2{q} | (1) |
ΔTtotal = 320 – 200 = 120 | ΔTtotal = 320 – 200 = 120 | (2) |
h1 = .40(ΔT1).33 | ΔT1 = 1.99q.75 | (3) |
twall/kwall = .05 | ΔTwall = .05q | (4) |
h2 = .80(ΔT2).50 | ΔT2 = 1.16q.667 | (5) |
U = 1/(1/.4(ΔT1).33 +.05 + 1/.8(ΔT2).50) | 120 = 1.99q.75 + .05q + 1.16q.667 | (6) |