Abstract: The current work covered the investigation of the effect of powder reinforcement on the buckling load of orthotropic hyper composite plate composed from powder and unidirectional or woven reinforcement and resin materials . An analytical solution has been suggested to evaluate the buckling load of orthotropic hyper composite plate. The general equations of properties of hyper composite plates have been presented taking into consideration the effect of powder reinforcement and unidirectional of woven and resin materials. The finite element method using Ansys Package Ver. 14 was employed. The comparison has shown a good agreement with a maximum discrepancy of ( 1.9% ). The results cover the determination of buckling load of simply supported orthotropic hyper composite plates manufactured from powder reinforcement and unidirectional or woven fiber and resin materials with different volume fractions. Also ,the results showed that the buckling load of the plate is increasing with the increase the reinforcement powder and slightly affected by the powder reinforcement types. Also, it has been shown that the buckling load increases with the increase the unidirectional or woven reinforcement fiber is more than the increase in the buckling load of composite with the increase of powder reinforcement.

Abstract: With the prevalence of mobile devices, many organizations achieve the concept of BYOD (Bring Your Own Device) through MDM for their visitors and employees’ convenience and security. However, device control of mobile devices at application level may be weak against the fundamental security problems. In this paper, we propose a more flexible and more secure method to control the hardware devices using LSM (Linux Security Module) with the mandatory access control at the embedded Linux kernel level.

Abstract: Numerical study of turbulent flow in orifice plate within a pipe is carried out by utilizing the Navier-Stokes (N-S) equations. These equations are numerically solved using primitive variables with a finite volume method, and simulated using the based commercial CFD code ANSYS. The N-S equations are solved for flow patterns that are presented for unsteady flow of an orifice plate at different values of Reynolds number and aspect ratios. The study is performed at Reynolds numbers of 5000, 10000, and 15000 and at aspect ratios of 0.2, 0.3, and 0.5. The results demonstrate the following parameters: velocity profile, differential Pressure, and vorticity of the flowing fluid inside the pipe and around the orifice. The study also demonstrates the mechanical effects caused by the flow passed the orifice such as stress, strain, and total deformation. It is found that as Reynolds number increases the flow velocity increases, while the differential pressure shows very steep jump across the orifice. Concerning the vorticity, the images show that both Reynolds number and the aspect ratio influence the structure of the flow that passes the orifice. The mechanical properties are found to be strongly affected by both Reynolds number and aspect ratios.

Abstract: In this work, laminated composites based on epoxy resin reinforced with woven mengkuang fibre were studied in detail. Woven mengkuang fibres were treated with various concentrations of NaOH (2.5%, 5.0%, 7.5% and 10%) during 90 minutes of soaking time. The effect of the alkali treatment on the rate of the critical strain energy release, GIIC was analysed. The influence of weight fraction on the laminated composites was also investigated. Two (2) layer and four (4) layer based woven mengkuang fibre reinforced epoxy composites were fabricated using the hand lay-up method with cold press. Analysis using the Direct Beam Theory (DBT) on the GIIC showed that the 2-layer based composites give an inconsistent value of GIIC due to the lower fibre weight fraction, i.e. around 17-18 wt. % compared to the 4-layer based composites, which are around 50 wt. %. From the experimental investigation that focused on the 4-layer based composites, it was found that the 7.5% NaOH treated woven mengkuang fibre reinforced epoxy laminated composites behave well in terms of GIIC compared to the other treated and untreated woven mengkuang fibre laminated composites.

Abstract: In this paper optimization of the design parameters and the effects of them on performance of Polymer Electrolyte Membrane Fuel Cells (PEMFCs) has been performed. The computational fluid dynamics (CFD) technique is used to optimize channel domains that have important effect on PEMFCs performance. The result of the optimization process show optimal channel parameter values for single channel configurations. In this study, contrary of some of the last works, the material properties are considered variable in each of the simulations and obtained results are compared with them.

Abstract: This study mainly explores the effects of powder additive in dielectric fluid when electrical discharge machining of Inconel 718 by employing high Peak current and Pulse duration. Copper was selected as a tool. Peak current, Pulse duration, and Concentration of the nano Alumina powder were chosen as a variable parameter to study the EDM performance in terms of Material removal rate (MRR), Electrode wear rate (EWR) and Surface roughness (Ra). The experiment results show that, the MRR has improved significantly compared to without powder concentration at a high level of Peak current and Powder concentration for both electrodes. When EDM machining at 4g/l of powder concentration, the MRR is improved about 32% in comparison to the highest MRR value obtained without powder suspension dielectric. The maximum MRR value 45.70mm3/min was obtained at 40A of Peak current, 200µs of Pulse duration and 4g/l of powder concentration. In conventional EDM, the EWR is increased at high peak current and shortest pulse duration. But when powder suspension was applied, higher peak current and longer pulse duration was decreased the EWR. The lowest EWR value -0.244mm3/min was achieved at the highest powder concentration 4g/l with the highest value of Peak current of 40A and the longest Pulse duration of 400µs. The negative value for EWR is indicated that the deposition effect has occurred on the electrode surface. The value of Ra also increased by increasing of peak current but decreased with longer pulse duration. The Ra value is worst when powder concentration was applied. The result suggested that, lower peak current with longer pulse duration and without powder additive in a dielectric is better for Ra. The lowest Ra value 8.98µm is obtained at 20A of Peak current and 400µs of Pulse duration without powder suspension dielectric.

Abstract: The melt spinning technique has been used in this study to produce rapidly solidified alloys in the simple binary Al-Sn alloys.Aluminum-5,15 and 25%Sn were prepared by as cast and melt spun technique. Optical microcopy,X-rays diffraction analysis and scanning electron with energy dispersive spectroscopy (EDS) were used to provide information about the difference in microstructure and phases of as cast and rapid solidified samples. In addition to hardness values of the ribbons and as cast ingots also measured. The results revealed that microstructure of the as cast alloys is formed from Sn particle spread in a continuous Al-rich matrix, moreover thin predendritic fine chill crystal zone at the wheel side with only Sn-rich phase particles, which develops into a region of disordered dendritic columnar grains. There is no solubility of Al in Sn or vice versa in thermal equilibrium diagram of aluminum-tin alloy system at room temperature; also, there is no intermediate phase formed between Al and Sn by conventional production processes. X-ray diffraction has ascertained the presence of the equilibrium phases for rapid solidified alloys. The hardness values of melt-spun alloys increase approximately twice higher than those of original ingot alloy.

Abstract: Maintaining the appropriate temperature is critical for enhancing fuel cell efficiency in fuel cell automobiles. Thus, this paper optimized the 3-way valve of the fuel cell thermal management system through normal and abnormal state analyses. The analysis results showed that when the inlet and outlet valve angles increase, the pressure difference decreases, resulting in an increase in the efficiency of the 3-way valve. Also, since the temperature and flow rate of the coolant are almost constant at the valve exit, even when the valve opening and closing speeds were increased to 1.8 rad/s, the fuel cell load has to be addressed preferably with increased valve opening and closing speeds.

Abstract: The thermal management of electric vehicle (EV) batteries plays an important role in ensuring that the batteries operate within a safe range. Therefore, the liquid cooling method was used to design and fabricate an effective thermal management system. Three different liquid cold plates (LCP) with fin spacings of 2.0 mm, 3.0 mm and 4.0 mm along the oblique fins were investigated. Ethylene glycol was used as the coolant. In this experiment, a heater block was used as a heat source in place of the actual battery, while a heater power of 300 W was used as the heat load. At this heat load, the surface temperature of the aluminium block could reach up to 200 °C. The lowest heater surface temperature of 44 °C was achieved by using a liquid cold plate with a fin spacing of 2.0 mm, whereas the highest heater surface temperature of 54 °C was achieved by using a liquid cold plate with a fin spacing of 4.0 mm. The experimental results showed that the surface temperature of the heater dropped when the fin spacing decreased and the flow rate of the coolant circulating through the cooled plate increased. Based on the surface temperature of the heater for the three different liquid cold plate fin spacings, the battery managed to operate within the permitted working temperature of below 50 °C.

Abstract: The mechanical behavior of metal matrix composites is dependent on matrix alloy and reinforcement. The presence of reinforcement elements significantly affects the nature of matrix microstructure. Extrusion process is preferred to produce aluminum alloy at a maximum production rate and a minimum scrap. The extrusion pressure requirement and the maximum temperature of the extrudate depend on the alloy and its metallurgical conditions. In this paper, characteristics of Al 2124/SiCp composites during hot working (extrusion) have been investigated. Extrusion tests have been conducted on composites with different volume fraction of SiCp (0%, 10%, and 20%). Also tensile tests were carried out to investigate the yield strength and ultimate strength of the extruded samples. The results showed that extrusion pressure decreased with increasing extrusion temperature because of the decrease in plastic flow stress. The extrusion pressures of the composites were much higher than those of 2124 Al Alloy because the silicon carbide particles act as hard inclusions. For extrusion pressure, empirical models have been developed. Also the extrusion pressure of 2124 Al composites have been predicted by using the constitutive equations obtained from the experimental results.

Abstract: In this research, the analytical solution of the general equation of bucking behaviors of composite plate is investigation. The composite materials studied are isotropic hyper composite materials plate combined from three materials as reinforcement powder, mat or short reinforcement fiber and resin materials. The results evaluated are the buckling load of isotropic hyper composite simply supported plate with different aspect ratio of plate (AR=0.5,1 and 2), various volume fraction of reinforcement powder and fiber, and different reinforcement and resin materials types. The theoretical results evaluated compare with numerical results evaluated with finite element method by using Ansys program ver. 14, where, the compare between the theoretical and numerical results shown a good agreement with maximum error about (2.7%). The results shown that the buckling load of plate increasing with increase of the reinforcement powder and the buckling load non effect with the powder reinforcements types. Also, the results shown that the buckling load increases with increase the mat or short reinforcement fiber more than the increases of the buckling load of composite plate with increase of powder reinforcement. And, the buckling load increasing with increase the modulus of elasticity of resin materials types used.