Open Adsorption Desiccant Wheel Air Conditioning System Simulation And Experimental Study

The main advantage that an open-cycle rotary desiccant air conditioningsystem offers is the capability of using low-grade thermal energy andenvironmental protection, so it has been generally regarded as one of theprimary technologies for substituting CFC's conventional refrigeration systemin the 2fth century. The key problem which commercializes the systems iscoupled heat and mass transfer processes and mechanisms and ways ofenhancement in rotary dehumidifier, which is the main component of adesiccant air conditioning system. The performance of open-cycle desiccant airconditioning system and its factors influencing performance have beeninvestigated experimentally and theoretically. Multidimensional dynamicmodel which describes the simultaneous heat and mass transfer processes thatoccur in an rotary desiccant dehumidifier has been set up. A numerical schemeRHDMX has been developed for simulating the performance of rotarydehumidifier and the entire system .The numerical method is of high-orderaccuracy, is numerically implicit, and is unconditionally stable. This methodallows for more rapid simulation of the performance of rotary desiccantdehumidifier and air conditioning system. Considering the circumferentialconvection is the most important feature for RHDMX. The effects of desiccantsorption properties, the heat and mass transfer characteristics of the matrix andstructure parameters of rotary dehumidifier on the performance of the systemhave been investigated. The relationships between the operating parameters ofsystem are optimized. This paper presents two novel ideals of enhancingcombined heat and mass transfer for rotary dehumidifier : The first is to notonly enhance desiccant properties of LiCl but also reduce regenerationtemperature of LiCl by adding the additives which are kinds of high polymercompounds with cross-linked net structure . These additives have thecohesion after absorbed salt solution, so LiCl mass fraction can be increased.As it increases, the moisture sorption capacity of the wheel increases and thecooling capacity of the system also increases appropriately; The second is tochange the structure of adiabatic rotary dehumidifier into cross-flow type. Inan rotary dehumidifier, this cross-flow arrangement has the advantage of easy...