شبيه‌سازي و بهينه‌سازي ابعاد دهانه ورودي سايكلون گاز-ذره به كمك تكنيك هاي ديناميك سيالات محاسباتي

3D Simulation Optimization of gas –solid cyclone separator of intance dimention using fluent software

خلاصه – در اين پژوهش بهينه‌سازي ابعاد دهانه ورودي سايكلون با در نظر گرفتن دو تابع هدف افت فشار و راندمان جداسازي به كمك تكنيك هاي ديناميك سيالات محاسباتي صورت گرفت. به‌منظور صحه‌سنجي شبيه‌سازي. نتايج با نتايج تجربي مقايسه شد شبيه‌سازي تطابق رضايت بخشي با نتايج تجربي داشت و ميانگين خطاي مدل‌سازي كمتر از 10درصد به دست آمد نتايج نشان داد افزايش عرض يا ارتفاع ورودي سايكلون افت فشار را به بهاي افزايش قطر برشي كاهش مي‌دهد. سايكلون‌هاي با ورودي عريض‌تر مطلوب نيستند. تأثير تغيير عرض ورودي روي قطر برشي در مقايسه با تأثير ارتفاع ورودي چشمگيرتر است. همچنين نسبت بهينه عرض ورودي به ارتفاع ورودي b/a بين 0.5 الي 0.7 به دست آمد. در اين نسبت هر دو تابع هدف وضعيت به نسبت مطلوبي دارند در اين بازه ميزان افت فشار در حدود 100 پاسكال و مقدار قطر برشي نيز قابل‌قبول و در حدود 1/1 تا 3/1 ميكرومتر است. كليدواژه‌ها: سايكلون، بهينه‌سازي، ديناميك سيالات محاسباتي، قطر برش

Due to the benefits of cyclone separation, which include low costs of construction, installation, and maintenance, they are widely used in various industries. Because of the cost and time consuming of cyclone manufacturing, it’s better to have a software simulation. The particle residual time, separation efficiency, minimum separation cut of diameter, pressure drop and particle and gas flow patterns accurately were calculated. In this way, geometry was generated in Catia V.5 software, mesh generation was done by Ansys and finally, simulation was performed using Ansys-Fluent. The mass and momentum equations were solved in a turbulent flow filed. For validation, the simulation results were compared with experimental results. The obtained Simulation results were in good agreement with experimental results and the mean modeling error for the axial velocity profile was less than 15%, which indicating that the RSM model could simulate vortex flows properly. In the following, cyclone optimization was performed for two objective functions, the cut-off diameter and pressure drop were considered as these two objective. The dimensions of the cyclone inlet were considered as Independent variables. In order to optimization, the five cyclones with different height and width inlet dimension were simulated and the results are as follows: Increasing the width or height of the inlet of the cyclone reduces the pressure drop to the cost of increasing the cut off diameter. Optimization results show that widescreen cyclones are not desirable. The effect of changing the width of the inlet on the cut off diameter is more significant than the effect of the inlet height. The optimum inlet width to the height (b/a) is between 0.5 and 0.7. In this ratio, both objectives function are in good condition. In this interval, the pressure drop is about 100 Pascal and the cut off diameter is also acceptable and about 1.1 to 1.3μm