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How do you correctly calculate the heat transfer load?

How do you correctly calculate the heat transfer load?

How do you correctly calculate the heat transfer load?

I'm trying to determine the heat transfer load of a sealed cabinet I'm a bit confused about the formula that is apparently used for it. I would appreciate some help. The formula is:

(q = (To - Ti ) ÷ [(1/ho ) + (1/hi ) + R] x 5.67

Definition of Variables— q = Heat transfer load per unit of surface area To = Maximum ambient temperature outside the enclosure Ti = Maximum rated temperature of the electrical components ho = Convective heat transfer coefficient outside the cabinet Still air: h = 1.6 Relatively calm day: h = 2.5 Windy day (approx. 15 mph): h = 6.0 hi = Convective heat transfer coefficient inside the cabinet Still air: h = 1.6 Moderate air movement: h = 2.0 Blower (approx. 8 ft.3/sec.): h = 3.0 R = Value of insulation lining the interior of the enclosure walls No insulation: R = 0.0 1/2 in. or 12 mm: R = 2.0 1 in. or 25 mm: R = 4.0 1-1/2 in. or 38 mm: R = 6.0 2 in. or 51 mm: R = 8.0

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