Journal of Advanced Research in Fluid Mechanics and Thermal Sciences 40, Issue 1 (2017) 18-26 18 Journal of Advanced Research in Fluid Mechanics and Thermal Sciences Journal homepage: www.akademiabaru.com/arfmts.html ISSN: 2289-7879 Wind Tunnel Experiments on a Generic Sharp-Edge Delta Wing UAV Model Nadhirah Mohd Zain 1 , Shabudin Mat 1,* , Khushairi Amri Kasim 1 , Shuhaimi Mansor 1 , Md. Nizam Dahalan 1 , Norazila Othman 1 1 Department of Aeronatical, Automotive and Offfshore Engineering, University Teknologi Malaysia, 81310 Johor Bahru, Malaysia ARTICLE INFO ABSTRACT Article history: Received 2 November 2017 Received in revised form 1 December 2017 Accepted 24 December 2017 Available online 26 December 2017 Delta wing is a triangular shape platform from a plan view. Delta wing can be applied to aircraft development as well as UAV. However, the flow around delta wing is very complicated and unresolved to date. On the upper surface of the wing, vortex is developed which need more studies to understand this flow physics. This paper discusses an experiment study of active flow control applied on the sharp-edged generic delta wing UAV. This paper focuses on the effect of rotating propeller on the vortex properties above a generic 550 swept angle model. The model has an overall length of 0.99 meter and the experiments were performed in Universiti Teknologi Malaysia Low Speed wind tunnel sized of 1.5 x 2.0 meter2. In this experiment, the experiments were conducted at a speed of 18 m/s. In order to differentiate the effect of propeller size on the vortex system, the experiment was carried out in three stages, i.e., experimental without propeller called as clean wing configuration and followed by the experiment with propeller diameter of 13”. The final experiment was the experiment with propeller diameter of 14”. During the experiments, two measurement techniques were employed; steady forces and surface pressure measurements. The experimental data highlights an impact of propeller size on the coefficients of lift, drag, and moment and vortex system of the delta-shaped UAV. The results obtained indicate that the lift is increased particularly at high angle of attack. The results also show that vortex breakdown is delayed further aft of the wing when propeller rotating at about 5000 RPM. Keywords: Delta Wing UAV, Propeller, Vortex, Wind Tunnel Experiment, Surface Pressure Copyright © 2017 PENERBIT AKADEMIA BARU - All rights reserved 1. Introduction Delta wing is commonly used for high speed application as its advantage can sustain lift force at higher angle of attack [1]. Nonetheless, delta wing configuration also can be applied in micro air vehicle (MAV) and unmanned aerial vehicle (UAV) because its weight effectiveness and the structure of a delta wing that is rigid [2]. Delta wing produced more lift at higher angle of attack because of the vortex formed near the leading edge [3, 4]. Strong vortices generate at higher angle of attack produce high speed flow above the wing, resulting in low pressure region above the wing [5, 6]. Thus, the wings lift increase significantly. The formation of leading edge vortex is affected by * Corresponding author. E-mail address: shabudin@utm.my (Shabudin Mat) Penerbit Akademia Baru Open Access