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A large value of temperature difference will lead to more condensation and hence a __________ heat transfer coefficient

A large value of temperature difference will lead to more condensation and hence a __________ heat transfer coefficient Correct Answer Smaller

A large temperature difference will lead to more condensation on the wall and bigger condensate thickness which will lead to a small heat transfer coefficient.

Related Questions

Which are the correct statements? (a) Film condensation usually occur on oily surface. (b) Temperature of condensate gradually increases towards the liquid-vapour interface. (c) Suitable coating is used to promote dropwise condensation. (d) Dropwise condensation gives lower heat transfer rate than film condensation.
Experimental results indicate that the local heat transfer coefficient h g for flow over a flat plate with an extremely rough surface is approximated by the relation h x = a x -0.12 Where a is a constant coefficient and x is distance from the leading edge of the plate. What is the relation between this local heat transfer coefficient and the average heat transfer coefficient for a plate of length x?
Statement 1: Film-type condensation has a higher heat transfer co-efficient than drop-wise condensation. Statement 2: Drop-wise condensation is easier to maintain than Film-type condensation
Consider the following statements (i) If a condensing liquid does not wet a surface, then drop wise condensation will not take place on it (ii) Drop wise condensation gives a higher transfer rate than film wise condensation (iii) Reynolds number of condensing liquid is based on its mass flow rate (iv) Suitable coating or vapor additive is used to promote film wise condensation Identify the correct statement
A stream of air at 100 kPa pressure and 300 K is flowing on the top surface of a thin flat sheet of solid naphthalene of length 0.2 m with a velocity of 20 m/sec. The other data are: Mass diffusivity of naphthalene vapor in air = 6 * 10 –6 m2/sec Kinematic viscosity of air = 1.5 * 10 –5 m2.sc Concentration of naphthalene at the air-solid naphthalene interface = 1 * 10 – 5 kmol/m3 Calculate the overage mass transfer coefficient over the flat plate. Note: For heat transfer over a flat plate, convective heat transfer coefficient for laminar flow can be calculated by the equation. Nu = 0.664 ReL1/2 Pr1/3 you may use analogy between mass and heat transfer.
The scales form in heat exchanges after a period of operation and provide additional resistance to heat transfer with some heat transfer coefficient . The reciprocal of this scale heat transfer coefficient is called .
A heat exchanger with heat transfer surface area A and overall heat transfer coefficient U handles two fluids of heat capacities Cmax and Cmin. The number of transfer units (NTU) used in the analysis of heat exchanger is specified as
A heat exchanger with heat transfer surface area A and overall heat transfer coefficient U handles two fluids of heat capacities Cmax and Cmin. The number of transfer units (NTU) used in the analysis of heat exchanger is specified as
In a surface condenser, the water flowing through a series of tubes at the rate of 200 kg/hr is heated from 15 degree Celsius to 75 degree Celsius. The steam condenses on the outside surface of tubes at atmospheric pressure and the overall heat transfer coefficient is estimated at 860 k J/m2 hr degree. Find the number of transfer units of the heat exchanger. At the condensing pressure, stream has saturation temperature 0f 100 degree Celsius and the latent heat of vaporization is 2160 k J/kg. Further, the steam is initially just saturated and the condensate leaves the exchanger without sub-cooling i.e. only latent heat of condensing steam is transferred to water. Take specific heat of water as 4 k J/kg K
An average convective heat transfer coefficient for flow of air over a sphere has been measured by observing the temperature-time history of a 12 mm diameter copper sphere (density = 9000 kg/m3 and c = 0.4 k J/kg K) exposed to air at 30 degree Celsius. The temperature of the sphere was measured by two thermocouples one located at the center and the other near the surface. The initial temperature of the ball was 75 degree Celsius and it decreased by 10 degree Celsius in 1.2 minutes. Find the heat transfer coefficient