The experiment data obtained are aimed for validating detailed design and development processes for varied aerodynamic applications. NACA airfoils were designed and developed at NASA Langley laboratory primarily for testing its aerodynamic performance. Therefore, use of boundary element methods such as 2D or 3D panel are recommended for obtaining faster and reliable results which can be readily used for validation with experiments or with other numerical methods such as computational fluid dynamics (CFD). For many applications of fluid dynamics, experiments are usually cumbersome to implement, due to complex wind tunnel setup of equipment, calibration, data recording, procedures. Panel methods are modern numerical techniques which execute faster and predict fairly accurate results compared to the experimental methods. Typically the results from experiment study serve as reliable validation step in aircraft industry which can be readily compared with numerical computations. In aerodynamic flow modeling, limiting Mach number value for incompressible flows is 0.3 while for compressible flows it is greater than 0.3. Reynolds number (Re) and Mach number (M). Most of aerodynamic flows can be characterized according to non–dimensional numbers viz. In addition, endurance and range are also important aerodynamic variables that impact the long run performance of aircraft. Glide or lift to drag ratio is an important parameter which affects the performance of an aircraft wing. The aerodynamic flow modeling is one of the core research areas in aviation industry and methods to control flow over finite span wings are aimed at analyzing the pitching, rolling and yawing moment behavior during operation. These forces are not fixed along the wing span and influences aerodynamic performance of aircraft wing. For a given angle of attack and Reynolds number, it not only affects the lift and drag force magnitudes but also the impacts the dynamic stability of an aircraft. In many aspects of aerodynamic research, the pressure coefficient and moment distribution for an airfoil provides important information related to lift and drag force characteristics acting on airfoil. Different types of NACA airfoils are defined based on the geometric properties such as chord length, camber, leading edge radius, as well as trailing edge angle and intended for commercial aircrafts, propellers and helicopters applications.
The lift is produced on low pressure or the suction side of airfoil surface as result of the pressure differential between the upper and lower surfaces of a wing. The lift generated on an aircraft wing is useful during takeoff, maneuvering, cruising and landing conditions. Most frequently lift and drag forces on airfoil are unsteady and non–uniform in nature that varies according to the flow conditions such as angle of attack and Reynolds number. NACA airfoils are used in the aircraft industry for generation of lift on wings of finite span length. Keywords: airfoil, panel method, pressure coefficient, angle of attack, chord Introduction The present results from the 2D panel method are validated using the results from Hess and Smith, inverse design methods implemented on conformal mapped symmetric Jukouwski airfoil of 10% thickness to chord at 40 angle of attack. The coefficient of lift and drag as well as glide ratio are evaluated for all three Reynolds numbers. The non–dimensional pressure coefficient along chord direction of airfoil is illustrated for upper and lower surfaces between –20 to 100 angle of attack. The analysis was conducted for various AOA (angle of attack), between –20 to 100 for the airfoil with tripped and untripped conditions. In the present work, surface pressure coefficient distribution of NACA 0010 is evaluated using the 2D panel and Jukouwski methods for incompressible lifting flows for three Reynolds numbers, Re–3 x105, 5 x105, 1 x 106. Computational methods are often used to predict the aerodynamic characteristics of such airfoils, typically the pressure, lift and drag force coefficients. Wing structures as found in aircrafts and wind turbine blades are developed using airfoils.
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