An increase in number of tubes will lead to larger condensate thickness in the lower tubes leading to ____________ heat transfer coefficient

An increase in number of tubes will lead to larger condensate thickness in the lower tubes leading to ____________ heat transfer coefficient Correct Answer Smaller

If the number of tubes increases then the condensate thickness too increases in the lower tubes leading to smaller heat transfer coefficient.
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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
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