الفهرس 
CHAPTER 1 INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
Delta wing shapes are unique in their structure advantages and aerodynamic characteristics. On supersonic design, a delta wing shape is often used to reduce drag and achieve optimal performance. An experimental and numerical simulation are conducted for three delta wing shapes (simple delta wing, cranked arrow delta wing, and ogival delta wing) at different angles of attack (5o to 65o). The experimental investigation is limited to the subsonic flow (M=0.15) while the numerical simulation which performed using commercial software (ANSYS 15) is performed at different subsonic and supersonic flow (M=0.15 to 1.4). For subsonic speeds (M=0.15 to M= 0.8) the results showed that, the stall occurs at different angles of attack depending on wing type and Mach number. It occurs at (45º to 50º), (38º to 42º) and (50º to 52º) for simple, cranked arrow and ogival delta wing, respectively according to Mach number, while at supersonic flow (M=1.2 and M= 1.4), the stall occurs at (40º to 45º), (30º to 32º), and (40º to 50º) for simple, cranked arrow and ogival delta wing respectively, and depending also on Mach number. at low angle of attack (α = 5º), either for subsonic or supersonic speed, cranked arrow wing has a higher lift to drag coefficient (higher performance) when compared to other wing types. For cranked arrow delta wing as Mach number increases, the maximum value of lift to drag coefficients increases by about 12% at Mach number 0.4 when compared to the value at Mach number 0.15 and angle of attack 15º. While for supersonic speed, cranked arrow wing has higher lift to drag coefficient with respect to the other two wings by about 16% at Mach Number 1.2. In contrast, for both ogival and simple delta wings, maximum lift to drag coefficient decreases by about 13% and 10% respectively at Mach number 0.8 when compared with that at Mach number 0.15. The results also showed that for angles of attack (α) > 5º, the ogival delta wing has the higher lift to drag coefficient which increases with decreasing Mach number, and the maximum value of lift to drag coefficients decreases by about 6% at Mach number 1.4 when compared to that at Mach number 1.2. Also, it is noticed that the pressure variation on the upper surface of the simple delta wing is the higher of the three investigated types while the cranked arrow delta wing surface is subject to minimal pressure variation which makes it more stable during the maneuvering process.