طراحي بهينه هندسه پروفيل دندانه پمپ هاي ژيروتوري

چكيده انگليسي :

Optimum Geometric Design of Gerotor Pump Tooth Profile Mohammad Reza Karamooz Ravari m karamoozravari@me iut ac ir 2010 12 19 Department of Mechanical Engineering Isfahan University of Technology Isfahan 84156 83111 IranDegree M Sc Language FarsiDr Mohammad Reza Forouzan Forouzan@cc iut ac ir AbstractThe Gerotor pumps are the most important positive displacement pumps which have a vast amount ofapplication in industries The Gerotors offer several advantages including simplicity of design low cost highefficiency low noise low flow ripple excellent durability single shaft design minimized parts common parts packaging flexibility and single or multi element arrangements These pumps are specially used in the mostinternal combustion engines as an oil pump Considering the applications of these pumps the optimization ofthem is more needed but the studies which concentrated on the optimization of the Gerotor pumps are slight Inthis project first the geometric equations of the Epitrochoid profile have been derived by using the envelopetheory and the volumetric and dynamic characteristics have been introduced according to the geometry of therotors profile The optimization problem cost functions included flow ripple wear rate proportional factor areaefficiency and influence area These cost functions have been developed according to the volumetric dynamicand geometric properties The non undercutting and pump volumetric displacement are the main constraints andhave been formulated too In order to have general optimum solution and reduce number of design variables allthe design variables except number of outer rotor teeth have normalized to the non dimensional variables byusing the outer rotor lobe center radius Using the normalized design variables causes the non dimensional costfunctions too By attention to integer variables and disconnected cost functions two mixed integer non linearoptimization programming MINLP methods namely the combination algorithm based on line up competitionand direct search and line up competition algorithm LCA have been used to optimize the single objectiveoptimization problem Considering more than one cost function it is necessary to change multi objectiveoptimization problem to single objective one The Global Criterion Method has been used to change multi objective optimization to single objective optimization problem The optimization programming has beenimplemented for several values of non dimensional displacement First the single objective optimizationproblems have been solved for each case and the optimum point optimum value optimum profile flow ratecurve and wear rate proportional factor curve have been resulted Then several combinations of multi objectiveoptimization problems such as lifetime and efficiency optimization have been studied On the other hand theinfluence of varied parameter such as number of rotors teeth and the value of non dimensional displacementhave been surveyed on each of the cost functions and the combinations of them Finally for better comparison several sample pumps which reported in literatures have been optimized by use of varied combination of costfunctions The results show significant improvement by considering only one cost function but in multi objective optimization problems the flow ripple cost function did not improve in some cases because the currentdesign point of some sample pumps is near the flow ripple optimum point Other cost functions that arementioned above have been improved in all cases The results show the lifetime and efficiency multi objectiveoptimization problems are the best configurations of the cost functions Also the optimum results which areobtained by both optimization methods are in agreement with each other which show the global optimization ofthe problems KeywordsGerotor Pump Epitrochoid Flow Ripple WRPF Area Efficiency Influence Area EnvelopeTheory Mixed Integer Optimization

كارآموز راوري، محمدرضا

طراحي بهينه هندسه پروفيل دندانه پمپ هاي ژيروتوري

پمپ اپي تروكايد , نوسانات جريان , نرخ سايش دندانه , بازده سطحي , بهينه سازي با اعداد صحيح آميخته