Heat Transfer The average heat transfer co-efficient over the entire length of the plate (ha) and the local heat transfer co-efficient (hL), in case of heat transfer over a flat plate in lminar zone is related as Ha= 5hL Ha = 0.8hL Ha = 2hL Ha = hL Ha= 5hL Ha = 0.8hL Ha = 2hL Ha = hL ANSWER DOWNLOAD EXAMIANS APP
Heat Transfer Graetz number is given by kL/mCp mCp/kL kμ/mCp mCp/kμ kL/mCp mCp/kL kμ/mCp mCp/kμ ANSWER DOWNLOAD EXAMIANS APP
Heat Transfer The critical radius of insulation for a spherical shell is (where, K = thermal conductivity of insulating material h0 = heat transfer coefficient at the outer surface) K/h0 h0/K h0/2K 2K/h0 K/h0 h0/K h0/2K 2K/h0 ANSWER DOWNLOAD EXAMIANS APP
Heat Transfer 1000 Kg of liquid at 30°C in a well stirred vessel has to be heated to 120°C, using immersed coils carrying condensing steam at 150°C. The area of the steam coils is 1.2 m² and the overall heat transfer co-efficient to the liquid is 1500 W/m².°C. Assuming negligible heat loss to the surrounding and specific heat capacity of the liquid to be 4 kJ/kg.°C, the time taken for the liquid to reach desired temperature will be 44 min 51 min 22 min 15 min 44 min 51 min 22 min 15 min ANSWER DOWNLOAD EXAMIANS APP
Heat Transfer While the total emissivity of a perfect black body is unity, the same for a real body is >1 0 1 between 0 and 1 >1 0 1 between 0 and 1 ANSWER DOWNLOAD EXAMIANS APP
Heat Transfer In a liquid-liquid heat exchanger, for the same process temperature, the ratio of the LMTD in parallel flow to the LMTD in counter flow is always ∞ < 1 > 1 1 ∞ < 1 > 1 1 ANSWER DOWNLOAD EXAMIANS APP