This research studies the wear characteristic of Al-based composite material. Stir casting technique was used to fabricate composite samples of Al-6061 and Al-6061 reinforced with different percentage ages (5%, 10%, 15% weight) of silicon carbide particles (SiC). Abrasive wear behavior of composite was studied by dry sliding pin on disc method. Different parameters were taken into consideration including, applied load, sliding speed, and weight percentage age of silicon carbide particles. Wear test-sliding distance ranged from 1044 m to 3123 m measured over different times (10 min, 20 min, and 30 min). Normal loads range from 10 N to 30 N, at sliding speeds of 1.74m/s. Specific wear rate was calculated considering weight loss calculation which was measured by using digital electronic balance (up to 0.01 g accuracy). The results show that by increasing the sliding speed and the applied load we get the highest wear rate in the aluminum alloy, while with the Al/SiC composite, the wear rate decreases with the increase of SiC percentage age. It was found that hardness increases simultaneously when SiC percentage age increases. The highest hardness in (AL-15 wt. % SiC) was recorded.

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The airflow around two-dimensional standard NACA 0015 airfoil effect was studied and analysed. The study was performed by simulating three geometrical modification airfoils (bumps NACA 0015, multi-element NACA 0015, and a backward-facing step NACA0015). Using SST (Shear Stress Transport) turbulence model and compared with standard NACA 0015 was the performed methodology. The research focuses on two cases (at different attack angles from 0 to 18 degrees with Re=1.65x106). Case I: the numerical analysis method data for the coefficient of lift of standard NACA 0015 (baseline case study) is compared to the previous experimental data. Case II: the coefficient of pressure, coefficient of lift, the contour of static pressure, and the velocity contour for standard NACA 0015(chord length c=1m) were calculated and compared with three geometrical modifications NACA 0015 airfoil. The CFD software ANSYS FLUENT version 17.1 was used for the computations in the present study. As a result, the geometrical modification influences on the aerodynamic properties of NACA 0015 was investigated. Compared to standard NACA 0015 airfoil, a significant improvement in the lift coefficient for multi-element NACA 0015 was noticed especially at the angle of attack (6°,14° and 18°) while slight improvement was noticed in the lifting coefficient for the other two models (bumps NACA 0015, and a backward-facing step NACA0015) at AOA 14 degree.

Abstract The purpose of this research is to investigate how the fiber orientation and loading axis of a composite material affect its behavior. Consideration was given to two different fiber-to-matrix ratios in order to improve the mechanical properties. Hand lay-up samples were produced in accordance with ASTM D790 for flexural testing. On UTM, tensile and flexural tests were performed on the sample. The effect of fiber orientation modifies the composites' mechanical properties. As the fiber orientation increased, the tensile strength of the composite would reduce. This carbon/epoxy composite test demonstrates better strength than those conducted at (30, 5, 60, and 90 degrees). For flexural tests, a three-point bend at 30 degrees demonstrates excellent strength. Utilizing the three-point bend method, the flexural strength and flexural modulus have been determined. The tensile strength, young's modulus, elongation percentage, maximum load to break the composite, peak load, and flexural strength of single- and double-layered carbon fibers were compared and examined. As the number of layers increased, the adhesion between layers of epoxy and fiber carbon, and glass fiber weakened, causing a decrease in almost all mechanical properties. The fabricated 2024-T3 and epoxy glass fiber had higher fatigue strength than aramid reinforced and lower density than steel alloy utilized in aircraft manufacture.

The aim of this paper is to control the flow separation above backward-facing step (BFS) airfoil type NACA 0015 by blowing method. The flow field over airfoil has been studied both experimentally and computationally. The study was divided into two parts: a practical study through which NACA 0015 type with a backward -facing step (located at 44.4% c from leading edge) on the upper surface containing blowing holes parallel to the airfoil chord was used. The tests were done over two-dimensional airfoil in an open circuit suction subsonic wind tunnel with flow velocity 25m/s to obtain the pressure distribution coefficients. A numerical study was done by using ANSYS Fluent software version 16.0 on three models of NACA 0015, the first one has backward-facing step without blowing, the second with single blowing holes and the third have multi blowing holes technique. Both studies (experimental and numerical) were done at low Reynolds number (Re=4.4x105) and all models have chord length 0.27m.The experimental investigations and CFD simulations have been performed on the same geometry dimensions, it has been observed that the flow separation on the airfoil can be delayed by using  velocity blowing (30m/s) on the upper surface. The multi blowing holes with velocity improved the aerodynamics properties.The multi blowing holes and single blowing hole thesame effect onpressure distribution coefficients