Design and Manufacture of Angular Oscillation Mechanism for Offensive and Defensive Models Testing With Mathematical Modeling

Document Type : Original Article



Considering the increasing threats and hostilities against our country, there is a great importance to design and build the basically status for model tests in the field of passive defense in wind tunnel with high attack angles and wide oscillations. In this regard, a mechanical test hardware is manufactured, which can provide the reciprocating pitch motion for wall model tests in a wind tunnel. This mechanism is manufactured to handle static and dynamic tests. At the dynamic mode, the mechanism can provide a verity of oscillation with the amplitude of ±6 degrees and the frequency up to 10 Hz, also it is capable to let the model have a high attack angle in dynamic or static tests. In this paper, after the introducing the dynamic pitching tests, the applications of a walled pitching test mechanism is presented. In the following the equations of motions are derived and some manufacturing process issues are discussed. Finally according to the experimental tests of a standard model (NACA0012) with an attach angle of 2 and 3 degrees at flow speed of 0.6 to 1.6 Mach and mentioned amplitudes and frequency , the results are presented in curve figures and are compared with the theoretical derived equations and real sine curves. The perusing of the resulted plots indicates the well adaptation of curves and high performance of the mechanism.


  1. داوری، رزاقی، سلطانی، بررسی اثرات حرکت نوسانی پیچشی روی مدل یک هواپیما بر نیروهای آیرودینامیکی توسط آنالیز طیف فرکانسی. هشتمین کنفرانس سالانه (بین المللی) انجمن هوافضای ایران، اصفهان، دانشگاه صنعتی مالک اشتر، 29 بهمن- 1 اسفند 1387.##
  2. داوری، حقیری، حسنی آهنگر، جهانگیریان، بررسی تجربی رفتار غیرخطی نیروی آیرودینامیکی یک مدل استاندارد دینامیکی در حرکت نوسانی پیچینگ. هفدهمین کنفرانس سالانه (بین المللی) مهندسی مکانیک، دانشگاه تهران 31-29 اردیبهشت 1388.##
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