Comparison Study Between Schrenk’s Approximation Method and Computational Fluid Dynamics of Aerodynamic Loading on UAV NACA 4415 Wing

Abstract

In early stage of wing structural design, the most important stage of structural analysis is to estimate the aerodynamics loading acting on wing. Years ago, several methods were used to estimate the aerodynamics distribution along span wise and were invented by few scientists. Each method takes different parameters into consideration. Yet, there is no proof whether these theoretical methods are able to provide an acceptable accuracy in estimating wing lift distribution. Schrenk method is commonly used among engineers in the early phase of an aircraft designing process based on its ability to provide fast result. Due to the advancement in technology, a computational fluid dynamics (CFD) has been created in order to get the high-level accuracy in aerodynamics prediction, where it uses Navier-Stokes equation to solve the simulation. NACA 4415 on Aludra MK1 UAV has been chosen to represent an aerodynamics analysis along with the wing span. This study focuses in verifying the Schrenk Approximation method using the computerize data-based analysis (CFD). The goal of this study is to determine the lift distribution along the NACA 4415 wing span and to acquire the percentage errors between Schrenk Approximation method and CFD method. From both studies, a significant aerodynamics lifting is obtained where the percentage difference between both methods are 3% for lift force and 13% for lift coefficient. Hence, Schrenk approximation method can be used for further application of aerodynamics lifting of UAV wing especially for structural analysis since the result proven within the acceptable and reasonable limit with CFD method.