Component Simulation And Visualization Computation Of Absorber In Fire-directed Absorption Chiller

With the frequently adjustment of energy policy and structure in China, natural gas issure to be the emphasis of energy development and utilization in 21 century. Fire-directedabsorption chiller shows the unique predominance in reducing the polluted gas exhausting,relaxing the power stress and adjusting the high load of power and natural gas supplement.So the fire-directed absorption chiller will play a promote role on traditional compressrefrigeration system. It's very known that absorption refrigeration system is units of many heat exchangers.Absorber and generator have the complicate dual-solution two-phase flow heat and masstransfer. In order to improve the heat and mass transfer coefficient and reduce the heatexchange area of each component, even in the evaporator and condenser which onlycontains the monadic-solution flow, absorption refrigeration system utilizes the falling filmevaporation and condensing technology. This complicate thermodynamic process makesthe modeling and description of each component harder and much work to realize thesimulation of whole absorption refrigeration system. Hence, this paper chooses the mostrepresentative absorber as the component-simulation object. Based on the thermodynamicproperties function of LiBr/Water solution and pure water, through mixing programming ofFortran and Matlab, and utilizes the powerful matrix computation, graph drawing, editperformance and graphic user interface of Matlab, comes true the visualizationcomputation and develops the toolbox of absorption refrigeration which supplies thefacilitate and useful tool for the following simulation design and visualization computation. Compared with the general single-tube model, this paper takes the horizontal bundleabsorber as the research object, analyses the principal of dual-solution two-phase flow heatand mass transfer in absorber, introduces the wetting ratio to describe the incompletewetting performance and view it as the changeable parameter to explain it's influence tototal performance of absorber and cooling capability of evaporator. The componentsimulation of absorber uses the falling and droplet model which divides the whole steamabsorption process of single tube into three zones, that is to say, falling film along the tubewall, droplet formation zone at the bottom of the tube and droplet fall between the tubes.Connecting with the three control differential function group, analyses the influence ofdifferent structure parameters such as number of horizontal tube, tube diameter, tube length,axial distance between tubes and running conditions such as solution mass flow rate,temperature, concentration, cooling water mass flow rate, inlet temperature andevaporative etc. to total performance of absorber and cooling capability of evaporator, andoriented from the simulation of Matlab, comes true the component simulation andvisualization computation of absorber. The way of modeling and simulation of absorber can also be expanded to otherthermodynamic component such as generator, evaporator and condenser, which will bebasis of the static and dynamic modeling and simulation of absorption refrigeration system.