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Ambient air at 20 ° C flows at a speed of 2.5 m / s on...
Ambient air at 20 ° C flows at a speed of 2.5 m / s on a hot spherical object with a diameter of 30 cm. If the average surface temperature of the object is 200 ° C, what is the average transport heat transfer coefficient during this process? = (For air, take k = 0.02514 W / mK, Pr = 0.7228, v = 1.798 x 10 m / s, Mo = 1.825 x 105 kg / ms, Ms = 2.577 x 105 kg / ms.)
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