الفهرس 
Introduction and Literature ReviewOnly 14 pages are availabe for public view
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Abstract
Condensation process from moist air flowing around horizontal pipe is investigated theoretically and experimentally. This process has many important engineering applications, such as the processes concerning moist air treatment, air conditioning applications and recovery of water from moist air. In the theoretical analysis of present work, the flow is assumed to be laminar, steady and of constant physical properties. The process is described by continuity, momentum, energy and mass partial differential equations expressed in Cartesian coordinates system. Due to the nature of the studied problem and with proper transformation of dependent and independent variables of the problem, these governing equations are retransformed to set of ordinary differential equations. Accordingly, the solution of this equations leads to similar solution of the problem. This solution is obtained by application of the wellknown numerical method of Rungkutta. According to this solution, one obtains the values of hydrodynamic, thermal and mass boundary layer thickness, Nusselt and Sherwood numbers for different values of Reynolds number and at different values of condensation and position parameters. In the experimental part of this investigation, air properties (humidity and temperature) and flow rate are varied to evaluate their effect on the heat and mass transfer coefficients. Chilled water flowing in a copper horizontal pipe is used to extract the heat load from the moist air, flowing through the outer surface of the pipe. The values of inlet temperature and relative humidity are measured before and after the test section at different values of flow rate, inlet relative humidity and temperature difference between the dewpoint of moist air at inlet and wall temperature. In accordance, heat and mass transfer coefficient are estimated for different operating conditions. Correlations of the problem parameters are proposed. According to the obtained experimental results the average heat and mass transfer coefficients increase with increasing flow rate and relative humidity of moist air at inlet, and decrease with increasing the temperature difference between the dewpoint of moist air at inlet and wall temperature.