Numerical Analysis Of The Wet Film Humidifier Performance

Artificial indoor environment includes two crucial indexes, temperature and humidity, and humidity has important significance on people living environment, which is one of the conditions to ensure health. In the industrial production process, we should control humidity in a range in order to produce qualified products. Humidifier is the tool to change the humidity.At present there are many kinds of humidifiers on the market, but wet film humidifier has more advantages,such as less equipment investment, high efficiency, energy saving, clean air, low noise, low water quality requirements and so on, so it get the promotion soon in the market.In this article, the physical model of wet film humidifier simplified into an abstract mathematical model, through ignoring the secondary factors (the system of humidifier water and air are thermal isolation, system conditions is stability, water in the metal surface can form even, stable water film, etc), and getting the main factors (packing thickness, pouring water density, air quality flows, etc). This is a crucial step, numerical calculation precision depends on the degree of the approximate of mathematical model and actual model.Establishment of differential control equations of wet film humidifier in heat and mass exchange process are established according to establishing mathematics model and the basic heat and mass transfer principle, with analysis the energy conservation and quality conservation. There still have many difficulties in mathematics theory solving, so this work adopts the numerical solution which is a common methods now. In numerical solution process, first the differential control equation should send into difference control equations. Then set the boundary conditions and lewis number and gets numerical solution. In the solving process, for comparing the results, the paper uses a single parameter changing method to calculate and computing results rolls into the form.Analyse a large number of data using the regression analysis method, then organize the numerical calculation results into experience formula which provide convenient for the solving of parameters and save the numerical calculation of trouble. According to analyse the results of numerical, we can gain the influence law of heat and mass transfer of wet film humidifier,which influents with packing thickness, air quality, pouring water density,etc, and the changing of export parameters (dry ball temperature, wet ball temperature, mass transfer coefficients, etc).Research of the work can provide the theory basis for wet film humidifier, can finish the design of wet film humidifier without doing any experiment, can save the test funds and can cut down the product development cycle. For other packing wet film humidifier,we can use the research ideas this topic, getting the influence of export parameters and mass transfer coefficients, which influents with packing thickness,, pouring water density, air quality flow,etc,and determine the reasonable parameters of packing thickness, pouring water density, air quality flow. This can save material and energy, and can meet the design results.