The Dietus-Boelter equation for convective leat transfercannot be used

1.	The Dietus-Boelter equation for convective leat transfercannot be used for
A.	low Reynold's number
B.	very low Grashoff number
C.	molten metals
D.	all (a), (b) and (c)
Answer» E.

Discussion

No Comment Found

Related MCQs

Hot water (0.01 m /min) enters the tube side of a counter current shell and tube heat exchanger at 80°C and leaves at 50°C. Cold oil (0.05 m/min) of density 800 kg/m and specific heat of 2 kJ/kg.K enters at 20°C. The log mean temperature difference in °C is approximately
A process stream of dilute aqueous solution flowing at the rate of10 Kg.s is to be heated. Steam condensate at 95°C is available for heating purpose, also at a rate of 10 Kg.s. A 1 - 1 shell and tube heat exchanger is available. The best arrangement is
A 10 cm dia steam pipe, carrying steam at 180°C, is covered with an insulation (conductivity = 0.6 W/m.°C). It losses heat to the surroundings at 30°C. Assume a heat transfer co-efficient of 0.8 W/m.°C for heat transfer from surface to the surroundings. Neglect wall resistance of the pipe and film resistance of steam. If the insulation thickness is 2 cms, the rate of heat loss from this insulated pipe will be
In the equation = Δ; Δ is
In Joule's experiment, an insulated container contains 20 kg of water initially at 25°C. It is stirred by an agitator, which is made to turn by a slowly falling body weighing 40 kg through a height of 4 m. The process is repeated 500 times. The acceleration due to gravity is 9.8 ms. Neglecting the heat capacity of agitator, the temperature of water (in °C) is
The heat flux (from outside to inside) across an insulating wall with thermal conductivity, K= 0.04 W/m.°K and thickness 0.16m is 10 W/m. The temperature of the inside wall is - 5°C. The outside wall temperature is
Steam consumption in kg/hr in case of an evaporator is given by (where, & are capacity the economy of the evaporator respectively)
With the increase of temperature, the Col-burn factor
Minimum recommended baffle spacing in a shell and tube heat exchanger is about (where, = shell diameter)
The equation, , corrosponds to __________ analogy.

The Dietus-Boelter equation for convective leat transfercannot be used for

Discussion

No Comment Found

Related MCQs

Reply to Comment