طراحی دیفیوزر برای یک تونل باد زیرصوت مکشی به کمک دینامیک سیالات محاسباتی

نوع مقاله: مقالة‌ تحقیقی‌ (پژوهشی‌)

نویسنده

عضو هیئت علمی پژوهشگاه هوافضا، وزارت علوم، تحقیقات و فناوری

چکیده

در این مقاله، طراحی دیفیوزر یک تونل باد زیرصوت مکشی که سه فن محوری نیروی رانش آن را تأمین می‌کنند، به کمک دینامیک سیالات عددی مورد توجه قرار گرفته است. اتاق آزمون تونل باد یاد شده به ابعاد cm140×cm195 است. برای مدل‌سازی فن محوری یاد شده که شامل 10 پره روتور و 13 پره استاتور می‌باشد و نیز در روند طراحی دیفیوزر و مدل‌سازی تونل باد از مدل‌سازی سه­بعدی پره‌ها استفاده شده است. این روش به بهترین شیوه، اثرات چرخش جریان را مدل می­کند. در بخش طراحی دیفیوزر سعی شد تا با بررسی حالات مختلف هندسی، دیفیوزری با بهترین عملکرد انتخاب شود. طرح نهایی دیفیوزری با زاویة مخروط معادل 4 درجه و طرح دایروی است. همچنین نشان داده شد که طرح دایروی در مقایسه با طرح­های سه­گوش و محاطی عملکرد بهتری از لحاظ افت فشار کل تونل باد و دبی عبوری از آن را دارد.

کلیدواژه‌ها


عنوان مقاله [English]

Design of a Diffuser for a Subsonic Wind Tunnel Using CFD

نویسنده [English]

  • Zoheir Sabohi
Faculty of Aerospace Research Institute
چکیده [English]

In this paper, the design of a diffuser for a suction type subsonic wind tunnel equipped with three axial fans has been taken into account by CFD. The tunnel test section has a 140 cm height and 195cm width. For numerical modeling the axial fans that contains 10 rotor blades and 13 stator blades 3D modeling to simulate the impeller have been used. The 3D modeling to simulate the impeller method provides an adequate means for simulating the swirl effects of air flow. The best geometrical characteristics have been selected for designing the optimal performance for the diffuser. The final design includes a circular diffuser which incorporates a 4 degree equivalent cone angle. This study also suggests that the circular scheme is superior to the triangular and fitted design aspect of the total pressure loss and the volumetric flow rate.

کلیدواژه‌ها [English]

  • Wind tunnel
  • Computational Fluid Dynamics
  • Diffuser
  • Axial fan
  • 3D modeling to simulate the impeller

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