عنوان مقاله :
پردازش سريع داده ها و طراحي معكوس آيروديناميكي با استفاده از روش رتبه كاسته ي تجزيه ي متعامد بهينه
عنوان فرعي :
FAST DATA PROCESSING AND INVERSE AERODYNAMIC DESIGN, USING LOW-DIMENSIONAL POD METHOD
پديد آورندگان :
مويدي، محمدكاظم نويسنده استاديار گروه مهندسي مكانيك، دانشگاه قم Moayyedi, M.K , طيبي رهني ، محمد نويسنده Taeibi-Rahni, mohammad , ثابت قدم، فريدون نويسنده ,
اطلاعات موجودي :
دوفصلنامه سال 1392 شماره 0
كليدواژه :
آيروديناميك تراكم پذير , روش تجزيه ي متعامد بهينه , روش رتبه كاسته , طراحي معكوس
چكيده فارسي :
در اين نوشتار از روش تجزيه‌ي متعامد بهينه )POD(proper orthogonal
decomposition (POD) براي تخمين سريع ميدان جريان، محاسبه‌ي
ضرايب و طراحي معكوس آيروديناميكي استفاده شده است. در اين رابطه دو روش
براي تخمين جريان تراكم‌پذير غيرلزج در رژيم‌هاي جريان متفاوت مورد
استفاده قرار گرفته كه هر دو روش تركيبي از روش تجزيه‌ي متعامد بهينه
)POD( است. روش‌هاي رتبه‌كاسته‌ي حاصل مي‌توانند با دقتي مناسب و سرعتي
بالا تغييرات در ميدان جريان ناشي از تغيير در پارامترهاي موثر
ازجمله عدد ماخ و زاويه‌ي حمله را پيش‌بيني كنند. براي طراحي
معكوس از يك مدل تركيبي مبتني بر روش تجزيه‌ي متعامد بهينه به‌همراه
يك مسيله‌ي بهينه‌سازي براي توزيع فشار سطحي يا كمينه‌سازي ضريب
پسا استفاده شده است. نتايج حاصله با شبيه‌سازي‌هاي عددي مستقيمdirect
numerical simulation (DNS و نتايج حل دقيق به‌عنوان مرجع مقايسه
شده كه دقت و سهولت چشمگيري را در محاسبات نشان مي‌دهد.
چكيده لاتين :
Lately, scientific and engineering computations have been receiving detailed
attention, in consequence of the improvement in computer hardware. Faster
processors, efficient memory modules, and parallel computation techniques have
prepared an adequate base for simulation of complex physical phenomena.
However, the challenges in performing a simulation of an engineering problem
and analyzing the attainable data increase manifold with the level of
difficulty in the governing equations. Despite this fact, attempts to
challenge these difficulties are inadequate. Numerical simulations yield large
sets of data, which may not be useful as an experimental assignment. These data
sets not only provide good and deep intuition into the physics of the problem,
but also simultaneously assist the assessment and enhancement of various models
that are developed for the computations.
In this article, Proper Orthogonal Decomposition (POD) has been used for fast
data estimation of flow the field, calculation of aerodynamical coefficients,
and inverse aerodynamic design. In this way, two methods have been used for
estimation of inviscid compressible flow fields in various regimes, in which
both methods are based on combined form of POD. The first extension is a
coupling between the POD method and a cubic spline interpolation, as
introduced for inviscid flows. The second is essentially a new technique,
which has been introduced by the authors for first time. In this method, some
additional calibrations (including a kind of re-projection) are needed to
achieve more accurate estimations. The outcome of these low order procedures
can predict variations of flow field, due to variations of some effective
parameters (e.g., Mach number or angle of attack) with high accuracy and high
speed of computation. For the inverse design, we used a combined model, based
on POD with the solution of an optimization problem, to obtain the desired
surface pressure distribution or to minimize drag coefficient. In this way, two
sets of snapshots have been used; an ensemble of flow fields, which may be
pressure distribution or any aerodynamic characteristics, and a geometrical
ensemble. The low order POD technique is used for computations of relative POD
modes and modal coefficients of these ensembles. To solve the coupled
optimization problem, an iterative approach has been used to achieve the
desired accuracy. Note that the present inverse design approach can be
reconstructed for different forms of the objective function. An order reduction
manner has been used to find the optimal number of modes for data
reconstruction that is a higher resolution of reconstruction which fewer modes
for data reconstruction. The obtained results are compared to CFD simulations
or exact solution results as reference data. The results show the relatively
good accuracy and also the simplicity of the procedure.
عنوان نشريه :
مهندسي مكانيك شريف
عنوان نشريه :
مهندسي مكانيك شريف
اطلاعات موجودي :
دوفصلنامه با شماره پیاپی 0 سال 1392
كلمات كليدي :
#تست#آزمون###امتحان
