In this study, the induced splined shaft teeth contact and bending stresses have been investigated numerically using finite element method(Ansys package version 11.0) with changing the most effecting design parameter,(pressure angle, teeth number, fillet radius and normal module), for internal and external splined shaft. Experimental work has been achieved using two dimensional photoelastic techniques to get the contact and bending stresses; the used material is Bakelite sheet type “PSM-4”.
The results of numerical stress analysis indicate that, the increasing of the pressure angle and fillet radius decrease the bending stress and increase the contact stress for both internal and external spline shaft teeth while the increasing of the normal module and teeth number decrease the contact and bending stresses
In this paper, we study the incorporation of the commensalism interaction and harvesting on the Lotka–Volterra food chain model. The system provides one commensal prey, one harvested prey, and two predators. A set of preliminary results in local bifurcation analysis around each equilibrium point for the proposed model is discussed, such as saddle-node, transcritical and pitchfork. Some numerical analysis to confirm the accruing of local bifurcation is illustrated. To back up the conclusions of the mathematical study, a numerical simulation of the model is carried out with the help of the MATLAB program. It can be concluded that the system's coexistence can be achieved as long as the harvesting rate on the second prey population is
... Show MoreBackground: Crohn's disease (CD) is an immunological disorder associated with chronic inflammatory process of several unspecific regions of gastrointestinal tract but frequently detected in the terminal Ilium and proximal colon or both. This disease frequently presented with various oral manifestations as a consequence of inflammatory process of the disease, nutritional deficiency or medications side effects. Several therapeutic approaches have been developed for CD management that are targeting the inflammatory process and directed at controlling the host immune response. Immunosuppressants such as Azathioprine and anti-TNF α agents as well as the combination of them have been widely used as an effective therapeutic modality with a bett
... Show MoreBackground: Pomegranate (punicagranatum L, Punicaceae), is an edible fruit consumed around the world. The edible part of pomegranate is rich in compounds that possess antioxidant and anti-inflammatory activities. The aim of this study is to investigate the antioxidant; anti-inflammatory and gingival wound healing effects of Punicagrantum L. seed extract oral supplementation in rabbit. Methods and Methods: Forty five male rabbits were divided into 3 groups, base line (5 rabbits) left without buccal gingival wound as( group 1),study group, 20 rabbits (group2) with buccal gingival wound treated with ethanolic extract of Punicagranatum L. seed extract and control, 20 rabbits (group 3) with buccal gingival wound only. Buccal gingival wounds w
... Show MoreTwo‐dimensional buoyancy‐induced flow and heat transfer inside a square enclosure partially occupied by copper metallic foam subjected to a symmetric side cooling and constant heat flux bottom heating was tested numerically. Finite Element Method was employed to solve the governing partial differential equations of the flow field and the Local Thermal Equilibrium model was used for the energy equation. The system boundaries were defined as lower heated wall by constant heat flux, cooled lateral walls, and insulated top wall. The three parameters elected to conduct the study are heater length (7 ≤
Metal foam has recently been used in many engineering applications, such as solar collectors, heat exchangers, and cooling of electronic devices, which calls for studying different cases of using metal foam in these applications. The current study conducts a numerical analysis of heat transfer and fluid flow characteristics for air in a rectangular channel filled with high-porosity copper foam. The study examined the thermal performance for two cases of gradient pore density, which are arranged as (10-20-40) PPI and (40-20-10) PPI. These cases were compared with two other cases for constant pore density, 10 and 40 PPI, and empty cases. The ANSYS FLUENT 20.0 employed the Darcy-Forchheimer extended Brickman model in the two-dimensiona
... Show MoreIn this study, the results of x-ray diffraction methods were used to determine the Crystallite size and Lattice strain of Cu2O nanoparticles then to compare the results obtained by using variance analysis method, Scherrer method and Williamson-Hall method. The results of these methods of the same powder which is cuprous oxide, using equations during the determination the crystallite size and lattice strain, It was found that the results obtained the values of the crystallite size (28.302nm) and the lattice strain (0.03541) of the variance analysis method respectively and for the Williamson-Hall method were the results of the crystallite size (21.678nm) and lattice strain (0.00317) respectively, and Scherrer method which gives the value of c
... Show MoreGas-lift technique plays an important role in sustaining oil production, especially from a mature field when the reservoirs’ natural energy becomes insufficient. However, optimally allocation of the gas injection rate in a large field through its gas-lift network system towards maximization of oil production rate is a challenging task. The conventional gas-lift optimization problems may become inefficient and incapable of modelling the gas-lift optimization in a large network system with problems associated with multi-objective, multi-constrained, and limited gas injection rate. The key objective of this study is to assess the feasibility of utilizing the Genetic Algorithm (GA) technique to optimize t