Concept explainers
A long bus bar (cylindrical rod used for making electrical connections) of diameter D is installed in a large conduit having a surface temperature of 30°C and in which the ambient air temperature is
(a) Recognizing that the electrical resistance per unit length of the bar is
(b) To assess the trade-off between current-carrying capacity, operating temperature, and bar diameter. for diameters of 10, 20, and 40 mm. plot the bar temperature T as a function of current for the range
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Fundamentals of Heat and Mass Transfer
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