Heat Transfer
A metal ball of radius 0.1 m at a uniform temperature of 90°C is left in air at 30°C. The density and the specific heat of the metal are 3000 kg/m³ and 0.4 kJ/kg.K respectively. The heat transfer co-efficient is 50 W/m².K Neglecting the temperature gradients inside the ball, the time taken (in hours) for the ball to cool to 60°C is
Presence of a non-condensible gas decreases the condensing film co-efficient
Gases to be heated/cooled is normally routed through the shell side, because the corrosion caused by the cooling water or steam condensate remain localised to the tubes
Gases under high pressure are routed through the tube side, because high pressure gases are corrosive in nature
EXAMIANS