Calculation And Evaluation Research On SEER Of Direct Evaporative Cooler

In this paper, basis on the definition of SEER of direct evaporative cooler, with threekinds of mode to select indoor design parameters respectively, which can determine themaximum allowable outdoor wet-bulb temperature evaporative cooler can work, basis onwhich to select Changdu, Yinchuan, Taiyuan as typical cites for SEER rating. Analysis theinsufficient of the rated conditions to calculate EER in existing national standards, determineconsistency outdoor calculated parameters as the rated conditions for SEER rating in typicalcites. Which can determine the cooling load point of the building cooling load lines, inaddition, according to the indoor design parameters to calculate and analysis the annualcooling load of rental shops in typical cites, which can determine the zero load point of rentalshops in typical cites, use dynamic method to determine the cooling season date in typicalcites, also statistics dry and wet bulb temperature and its hours distribution during coolingseason when need cooling.In addition, through analyzing the cooling capacity and power consumption of directevaporative cooler, then based on three fundamental assumptions:(1) building cooling load isa linear relationship with the outdoor dry bulb temperature;(2) the evaporation coolingefficiency is a linear relationship with the air flow of the direct evaporative cooler;(3) powerconsumption is a linear relationship with the air flow of the direct evaporative cooler. Take theactual air flow as a judgment, adopt the method of operation stages calculation, to obtain thecalculating formulas of actual cooling capacity and actual power consumption when directevaporative cooler in the continuous running stage of minimum air flow, in the continuousvariable air flow running stage between minimum and intermediate air air flow, in thecontinuous variable air flow running stage between intermediate and rated air flow, and in thecontinuous running stage of rated air flow. Finally it is concluded that the theory formula ofSEER calculation of direct evaporative cooler for the type (3-31).According to the theory formula of SEER calculation, take two direct evaporativecoolers which the rated flow is11000m3/h and20000m3/h respectively to be the experimental object, test the air flow, evaporative cooling efficiency and power consumptionunder different operation frequencies. And use the experimental data to fitting for evaporationcooling efficiency and power consumption as a function of air flow.Finally, calculates the EER under different rated conditions and the SEER in Changdu,Yinchuan, Taiyuan of the two direct evaporative coolers respectively, the calculation resultsshow that the cooler which the higher EER under the rated conditions is, the SEER value maybe relatively lower on the contrary. Then through the analysis of the calculation results, toprove the calculating method of SEER of direct evaporative cooler which gain in this paper, ismuch more scientific and reasonable than the calculating method of EER. Take SEER as anevaluation index of energy efficiency for direct evaporative cooler is more scientific, whichcan reflect the actual operation performance of direct evaporative cooler.