TY - JOUR ID - 72020 TI - Comparison of Lift and Drag Forces for Some Conical Bodies in Supersonic Flow Using Perturbation Techniques JO - International Journal of Engineering JA - IJE LA - en SN - 1025-2495 AU - Baradaran Rahimi, A. AD - Mechanical Engineering, Ferdowsi University of Mashhad Y1 - 2012 PY - 2012 VL - 25 IS - 3 SP - 231 EP - 238 KW - Supersonic flow KW - conical bodies KW - lift to drag ratio KW - squircle cross KW - section KW - Euler equations KW - perturbation techniques DO - N2 - Numerical methods are not always convergent especially in higher velocities when shock waves are involved. A comparison analysis is performed to study the supersonic flow over conical bodies of three different cross sections circular, elliptic and squircle (square with rounded corners) shaped usingĀ  Perturbation techniques to find flow variables analytically. In order to find lift and drag forces the pressure force on the body is found, the component along x is drag and the component along z is lift. Three equations are obtained for lift to drag ratio of each cross section. The graphs for L/D show that for a particular cross section an increase in angle of attack, increases L/D. Comparing L/D in the three mentioned cross sections depicted that L/D is the greatest in squircle then in ellipse and theĀ  least in circle. The results are efficient in design of flying objects. UR - https://www.ije.ir/article_72020.html L1 - https://www.ije.ir/article_72020_3cade3cbfaf99f22b88e5d2775f9ab43.pdf ER -