تحليل پاسخ آيروديناميك غيردائم ايرفويل و بال هواپيما، نسبت به توابع ورودي از تندباد

Unsteady Aerodynamic Analysis of Airfoils and Aircraft Wings to Gust Inlet Function

در اﯾﻦ ﻣﻘﺎﻟﻪ روش ﻣﺪلﺳﺎزي ﭘﺎﺳﺦﻫﺎي آﯾﺮودﯾﻨﺎﻣﯿﮑﯽ ﻫﻮاﭘﯿﻤﺎ ﺑﻪ ﭘﺮوﻓﯿﻞ ﺗﻨﺪﺑﺎد cos-1 اراﺋﻪ ﺷﺪه اﺳﺖ. ﻣﻮارد آزﻣﺎﯾﺶ در ﻧﻈﺮ ﮔﺮﻓﺘﻪ ﺷﺪه، اﯾﺮﻓﻮﯾﻞ دو ﺑﻌﺪي ﻧﺎﮐﺎ 0012 ﺟﻬﺖ ﺻﺤﺖ ﺳﻨﺠﯽ روش ﺑﮑﺎر ﮔﺮﻓﺘﻪ ﺷﺪه و اﯾﺮﻓﻮﯾﻠﻬﺎي دو ﺑﻌﺪي ﺑﺎل ﯾﮏ ﻫﻮاﭘﯿﻤﺎي ﺳﺒﮏ ﻧﺎﮐﺎ 23012، 23015 و 23016/5و ﻫﻤﭽﻨﯿﻦ ﺑﺎل ﺳﻪﺑﻌﺪي ﻫﻤﺎن ﻫﻮاﭘﯿﻤﺎ در ﻋﺪدﻫﺎي ﻣﺎخ 0/1 ، 0/2 و 0/3 ﻣﯽﺑﺎﺷﺪ. ﻓﺮض ﺑﺮ اﯾﻦ اﺳﺖ ﮐﻪ ﻣﻮارد آزﻣﺎﯾﺶ، ﺻﻠﺐ ﻫﺴﺘﻨﺪ و ﻓﻘﻂ ﭘﺮوﻓﺎﯾﻞﻫﺎي ﺗﻨﺪﺑﺎد، ﻃﻮﻟﯽ در ﻧﻈﺮ ﮔﺮﻓﺘﻪ ﻣﯽﺷﻮﻧﺪ. ﻧﺘﺎﯾﺞ ﺷﺒﯿﻪﺳﺎزي ﻧﺸﺎن ﻣﯽدﻫﺪ ﮐﻪ ﭘﺎﺳﺦﻫﺎي آﯾﺮودﯾﻨﺎﻣﯿﮑﯽ ﺗﻨﺪﺑﺎد 1 cos ﺑﻪ ﺧﻮﺑﯽ ﺑﺎ ﺗﺎﺑﻊ ﺗﻘﺮﯾﺒﯽ ﮐﻮﺷﻨﺮ ﻣﻮاﻓﻖ ﻫﺴﺘﻨﺪ. در ﺣﺎﻟﺖ دو ﺑﻌﺪي ﺑﺮاي ﯾﮏ اﯾﺮﻓﻮﯾﻞ ﺧﺎص ﺑﺎ اﻓﺰاﯾﺶ ﻋﺪد ﻣﺎخ، داﻣﻨﻪ ﺿﺮﯾﺐ ﺑﺮآي اﻓﺰاﯾﺸﯽ ﻧﺎﺷﯽ از ﺗﻨﺪﺑﺎد، اﻓﺰاﯾﺶ و ﻃﻮل ﻣﻮج، ﮐﺎﻫﺶ ﻣﯽﯾﺎﺑﺪ. ﺑﺎ اﻓﺰاﯾﺶ ﺿﺨﺎﻣﺖ اﯾﺮﻓﻮﯾﻞ در ﯾﮏ ﻋﺪد ﻣﺎخ، داﻣﻨﻪ ﺿﺮﯾﺐ ﺑﺮآي اﻓﺰاﯾﺸﯽ، ﺛﺎﺑﺖ ﻣﯽﻣﺎﻧﺪ وﻟﯽ ﻃﻮل ﻣﻮج، اﻓﺰاﯾﺶ ﻣﯽﯾﺎﺑﺪ. در ﺣﺎﻟﺖ ﺳﻪ ﺑﻌﺪي ﺑﺮاي ﯾﮏ ﺑﺎل ﺑﺎ اﻓﺰاﯾﺶ ﻋﺪد ﻣﺎخ، داﻣﻨﻪ ﺿﺮﯾﺐ ﺑﺮآي اﻓﺰاﯾﺸﯽ، اﻓﺰاﯾﺶ و ﻃﻮل ﻣﻮج، ﺛﺎﺑﺖ ﻣﯽﻣﺎﻧﺪ.

In this paper, the modeling method of aircraft aerodynamic responses to the 1-cos gust profile is presented. Test cases considered are, a twodimensional NACA0012 airfoil was used to verify the method and twodimensional NACA23012, NACA23015, and NACA23016.5 airfoils of the wing of a light aircraft and three-dimensional wing of the same aircraft in Mach numbers 0.1, 0.2 & 0.3. The test cases are assumed to be rigid and only gust profiles are considered longitudinal. The simulation results show that the aerodynamic responses of 1-cos gust agree well with Küssner approximate function. In the two-dimensional mode for a particular airfoil, as the Mach number increases, the amplitude of the incremental lift coefficient due to the gust increases, and the wavelength decreases. As the thickness of the airfoil in a Mach number increases, the amplitude remains constant, but the wavelength increases. In the threedimensional mode, for a wing by increasing the Mach number, the amplitude increases and the wavelength remain constant.