The fuel used in a boiler is having a calorific value of 25120 kJ/kg. The temperature of the gas leaving the economizer chamber is 260°C and is reduced to 150°C while leaving the pre-heater chamber. If 18 kg of air is supplied per kg of coal burnt and the efficiency of pre-heater is 80% determine (a) the percentage saving of heat of coal in the pre-heater, (b) the temperature of air leaving the pre-heater if the initial temperature of air is 27°C. Take Cp of air and flue gases equal to 1.05 kJ/kg.

The fuel used in a boiler is having a calorific value of 25120 kJ/kg. The temperature of the gas leaving the economizer chamber is 260°C and is reduced to 150°C while leaving the pre-heater chamber. If 18 kg of air is supplied per kg of coal burnt and the efficiency of pre-heater is 80% determine (a) the percentage saving of heat of coal in the pre-heater, (b) the temperature of air leaving the pre-heater if the initial temperature of air is 27°C. Take Cp of air and flue gases equal to 1.05 kJ/kg.

Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)

8th Edition

ISBN:9781305387102

Author:Kreith, Frank; Manglik, Raj M.

Publisher:Kreith, Frank; Manglik, Raj M.

Chapter1: Basic Modes Of Heat Transfer

Section: Chapter Questions

Problem 1.75P: Referring to Problem 1.74, how many kilograms of ice can a 3-ton refrigeration unit produce in a...

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