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Most artificial socket prostheses are applied to fatigue load; therefore, more failure of socket prostheses occur due to fatigue loading. Then, it was necessary to improve the fatigue characterizations of composite materials used to manufacture the artificial socket prostheses by using hybrid nanomaterials, with different types and amounts. So, this work suggested mixing two nanomaterials types to improve the mechanical and fatigue properties of composite materials. Therefore, the experimental work used to manufacture tensile and fatigue samples of composite with different nanoweight fraction effects, in addition to calculating the mechanical properties and fatigue behavior for its composite. There, strength and modulus of elasticity, in addition to, fatigue strength and life evaluating of composite with different nanomaterials mixing. Also, the numerical technique by using the finite element method is used to calculate fatigue life and strength of composite materials. Also, comparison fatigue results were calculated by experimental work with fatigue results evaluated by numerical technique to give the discrepancy for results evaluation. Hence, the comparison of results showed good agreement for the technique used to evaluate the fatigue behavior of composite materials with the nanoeffect, where, the maximum error did not exceed (11.86%). Finally, the results have shown that the reinforcement by mixing two Nanomaterial types lead to improvement in the mechanical properties and fatigue behavior to more than (35%) and increasing the mechanical properties and fatigue behavior to (10%) more than the increase of properties and fatigue characterizations reinforcement by one Nanomaterial type.

The water hammer (WH) phenomenon is one of the most dangerous phenomena in hydraulic systems, especially pipelines, gates, and locks on these lines. There are many analytical solutions to deal with the WH phenomenon, including the treatment of friction losses, but most solutions use linear arithmetic operations, which depart from the actual situation of the WH phenomenon. Also, the methods currently used are most challenging and complex and give imprecise results to treat the mentioned phenomenon. In order to reach a state closer to the situation of losses and stability of the hydraulic system that is close to the actual state, basic partial differential equations were used, taking into account the losses generated in the hydraulic system through mathematical conversion. MATLAB was used to program and solve equations, find mathematical results, draw system diagrams, and simulate a WH wave. Various parameters were investigated to show the stability behavior of the hydraulic system by using state-space Method. So, the effect of the pressure, flow rate, diameter, and fluid type were investigated to calculate the stability of the hydraulic system. The results evaluated showed that the system’s oscillation is less at lower pressure, and the stability period is longer than that at high pressures. In addition, the system needs a longer time to stabilize at the low flow speed due to pressure waves that occur. The stability of the system affected by the WH was examined, and the effect of fluid-specific variables such as velocity, pressure, and type of fluid in addition to the diameter of the pipe and their impact on WH stability was found. The behavior of stability at the WH is nonlinear, and that is why the linear and nonlinear parts of the governing equations of the structure are used to find system through the state-space method through programming and simulation of MATLAB program.

This research was aimed to perform a symmetric investigation regarding the influence of two types of nanoparticles, on some mechanical and morphological behaviors of the Kevlar/epoxy nanocomposites. Composites were prepared by dispersing nanoparticles of nano ZnO and TiO2 at loading of 1, 2 and 4 wt.% of each in (Kevlar/epoxy) composite using high speed mechanical mixer followed by sonication, then injecting them inside the cavity of a two plates glass mold. After curing they were characterized by tensile tests, flexural test, creep test and SEM. The results showed that the maximum increase of mean stress (41%) and the maximum flexural strength was obtained for system containing 4 wt.% of both nano ZnO and TiO2 particles, i.e., EKZ4 and EKT4 . SEM images for processed specimens were taken to observe the analogy distribution of both nanoparticles through the fiber/epoxy system. The improvement in the mechanical properties of nanocomposite EKT2 (2% TiO2)and EKZ2 (2% ZnO) attributed by the homogeneity of the nanoparticles distribution inside the epoxy which appear in SEM images. Also, the semispherical shape of nanoparticles led to uniform distribution of the nano particles inside Epoxy-keflar resin.