Chapter 1 Basics of Heat Transfer1-41The ducts of an air heating system pass through an unheated area, resulting in a temperature drop of the air in the duct. The rate of heat loss from the air to the cold environment is to be determined. Assumptions1 Air is an ideal gas since it is at a high temperature and low pressure relative to its critical point values of -141°C and 3.77 MPa. 2 The kinetic and potential energy changes are negligible, . 3Constant specific heats at room temperature can be used for air. This assumption results in negligible error in heating and air-conditioning applications. ΔΔkepe≅≅0Properties The specific heat of air at room temperature is Cp= 1.007 kJ/kg·°C (Table A-15). AnalysisWe take the heating duct as the system. This is a control volume
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This note was uploaded on 01/14/2012 for the course PHY 4803 taught by Professor Dr.danielarenas during the Fall '10 term at UNF.