5515

5175

كارشناسي ارشد

تبديل انرژي

اصفهان: دانشگاه صنعتي اصفهان، دانشكده مكانيك

1389

دوازده،82ص.: مصور،جدول،نمودار

ص.ع.به فارسي و انگليسي

احمد صابونچي

علي اكبر عالم رجبي

16/8/89

محسن ثقفيان، احمد صداقت

مهندسي مكانيك

ID5175

به فارسي و انگليسي: قابل رويت در نسخه ديجيتالي

Investigating the effect of dominant parameters on the wet cooling tower performance using mathematical modeling Ali Parsa a parsa@me iut ac ir May 15th 2010 Department of Mechanical Engineering Isfahan University of Technology Isfahan 84156 83111 Iran Degree M Sc Ahmad Saboonchi ahmadsab@cc iut ac ir Abstract The main idea of this project is to investigate the effects of different parameters on the performance of shower cooling towers based on a mathematical models The shower cooling towers are sorted in the category of wet and counter current cooling towers The main characteristics of this kind of cooling towers is the elimination of fill from the tower space and using of water flow distribution system in order to increase the contact surface between water drop and air As a result of this mechanism the water drops could fall down freely in the cooling tower space and perform heat and mass transfer simultaneously In our method by using mathematical tools and formulation conservation law of heat and mass transfer and simplification assumption a new mathematical model has been derived which describe the thermal behavior of cooling tower In this method a dynamical model for drops which are considered as a sphere is derived that result in a deferential equation for the drop velocity firstly Then with the simultaneously simulation of heat and mass transfer another four deferential equations is derived which declare the temperature alteration of water drop diameter alteration of water drop absolute air humidity and temperature of air Finally these five coupled equations which are first order nonlinear ordinary differential equations are solved numerically The velocity radious and temperature of droplet absolute hiumidity of air inlet air temperature height of tower and air to water mass ratio are determined in mathematical modeling that are effective parameters in the shower cooling tower performance The first five parameters are named cooling tower variables and the last three ones are constant Since outlet water temperature and mass ratio have used as the design parameters the variation of these parameters are ploted in terms of other parameters and presented in the conclusion section For this case the influences of air temperature absolute humidity droplet velocity droplet temperature hight of tower and air to water mass ratio on the outlet water temperature and mass ratio vaporization are investigated for several droplet radious The evaporation cooling efficiency is presented for cooling towers and the variation of the cooling tower efficiency due to the mentioned paramerters is investigated Key Words Cooling Tower Mathematical Modeling Outlet Water Temperature Efficiency

احمد صابونچي

علي اكبر عالم رجبي

محسن ثقفيان، احمد صداقت