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In regenerative air preheaters, the heat is transferred

In regenerative air preheaters, the heat is transferred Correct Answer From heating an intermediate material and then heating the air from this material

Related Questions

Are these statements about the regenerative heat exchangerstrue? Statement 1: Regenerators are commonly used in gas/gas heat recovery applications. Statement 2: Regenerative heat exchangers are also known as capacitive heat exchangers.
In recuperative air preheaters, the heat is transferred
Heat exchangers are used in A. Condensers and boilers in steam plants B. Radiators C. Intercoolers and preheaters D. Condensers and evaporators in refrigerators and air conditioners
Determine the correctness or otherwise of the following Assertion [a] and the Reason [r]. Assertion [a]: In a power plant working on a Ranking cycle, the regenerative feed water heating improves the efficiency of the steam turbine. Reason [r]: The regenerative feed water heating raises the average temperature of heat addition in the Rankine cycle.
A Carnot heat engine receives heat at 750 K and rejects the waste heat to the environment at 300 K. The net work output of the heat engine is used to drive a Carnot refrigerator, whose COP is 6.14. If the heat removal rate from the refrigerated space is 6.6 kW, determine the rate of heat supply to the heat engine?
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.
In regenerative air preheater (as practised in heating of coke ovens), the heat is transferred
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 effectiveness of the heat exchanger. At the condensing pressure, stream has a 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 the water. Take specific heat of water as 4 k J/kg K
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
In designing air preheaters, the important design consideration is that