Question

In stationary state operation, a transmission box receives 60 kW for the input arrow and powers the output arrow. The box loses energy by heat transfer at a rate defined by Newton's Cooling Law of Q = hA (Tb-Tf), where h = 0.171 kW / m2 * K, A = 1m2 is the surface area of the box, Tb = 300K is the external temperature and Tf = 20ºC is the surrounding air temperature, evaluate the power obtained from the transmission box, in kW.

To = 300 K We = -60 kW Tp = 293 K h = 0.171 kW/m2.K w Input shaft Gearbox Outer surface A = 1.0 m2 Output shaft

Answer 1

Given & heat received by trams mission box = 60kw or power transmission box loses energy at the rate of a=hACTO-4) = 0.177 kWmer X Im? x (300K - 293 k) - 0.17 kw x 7 = 11197 kW trams mission box So, heat release by - Gokw - 11197 kw - 58.803 kW or power So, Power obtained by transmission box = 58.803 kw