Journal of Engineering and Sustainable Development (JEASD)

In this paper, the static analysis for finding the optimum design of wing structure has been performed. The two types of wings for unmanned airplanes were chosen; the first wing was the taper designed at (M=0.71) and the other wing was rectangular designed at (M=0.21). The research covers both aerodynamic and structural design. The aerodynamic study was achieved by using the vortex lattice method and the structural analysis was achieved by using the Ansys 5.4 package where isotropic and composite materials wereused. From the results the mass saving of (32%) when composite material is used instead of isotropic material for the taper wing and (23%) for the rectangle wing. The optimum design for each wing was obtained according to the mass, stress, and displacement.

The principle of radar echo analysis for extracting the Doppler signal of moving echoes (eliminating fixed echoes) is based on the use of a sampler associated with a hold capacitor followed by a band-pass filter.The filter cut-off frequencies are chosen as a function of the types of targets to be detected. The fast filter has a pass-band from 190 Hz to 1800 Hz. These frequencies correspond to Fast targets having radial velocities of between approximately 10 Kph and 200 Kph.The slow filter has a pass-band from 60 Hz to 230 Hz. these frequencies corresponding to slower targets. Whose radial velocities lay between approximately 3.5 Kph and 13 Kph.

This paper presents an experimental investigation to predict the load-deformation behavior of High Strength reinforced concrete beams that failed in flexure and were repaired by epoxy injection. Four simply supported reinforced concrete beams with dimensions of (120*230*2550mm) were investigated after repairing with the epoxy resin injection method. Beams B1 and B2 have a tensile steel ratio of 0.0099, while Beams B3 and B4 have a tensile steel ratio of 0.0177. Deflections were measured at first third, second third from the support, and at mid-span for all beams by using dial gauges. The behavior achieved for resin-injected high-strength reinforced concrete beams was similar to that of the original beams. However, the cracks do not re-open after retesting. Instead, new nearby cracks are developed and the repaired beams showed a greater ductility than the original beams.

The design of a fluid power system that becomes more sophisticated needs good expertise in this domain. This work is based on prototype development to show the feasibility of integrating the field of expert systems and their application to hydraulic system design. The prototype developed in this work can be used as a design tool (for expert users) and an educational tool (for inexpert users). The first main key of this work is the ability of the development prototype of changing the required power unit type according to the different load attributes and the designer's limitations. The second key is the ability to prototype of sizing of components of the system according to the loads' quantities parameters. Also, the developed prototype helps the user to get a complete circuit design with low component expenditure and still achieve the required function.

This research deals with a modeling of the heating process of an induction furnace with a conducting non-ferromagnetic core. This is done by performing a sequential coupling between two types of analysis; the harmonic electromagnetic analysis and the transient thermal analysis in order to furnish a complete numerical simulation of this device.
The Finite Element Method (FEM) is considered in order to solve this problem using the "ANSYS" computer package. The proposed coupling algorithm deals with different heat treatment procedures by induction for any axi-symmetrical linear work piece has been built. The obtained results show a good agreement with the published practical measurements.
This work aids to declare the behavior of the furnace during the heating process, and
leads the designer to determine the required geometry of the furnace, its excitation current
and frequency suitable to do certain heat treatment of a defined work piece in shape and
composition. So, this algorithm is a computer aided design for a linear induction furnace
with rotational symmetry. This algorithm can be used to design such devices instead of the
traditional trial and error, experience dependant, design methods which lead to loss time,
money and efforts.

This research aims at obtaining the "Optimum safe hydraulic design of culverts", taking into consideration the cost of excavation, bedding, material, compacted fill, hunches, protection works, and additionally involved head loss.Because of numerous shapes and materials of culverts, the wide-fame among them have been selected in this research, namely, reinforced concrete box culverts of both rectangular and squared shape, and pipe culverts of circular shape with materials of reinforced concrete, cast-iron, asbestos-cement, and ductile-steel.To be close to field conditions, discharges of (0.5, 1.0, 1.5, 2.5, 5.0, 10.0, and 15.0m3/s) have been selected to represent small, medium, and big discharges; culverts lengths of (5, 10, 15, 20, 25, 35, and 40m) have been selected to represent short, medium, and long structures. However, typical trapezoidal earthen irrigation channels have been considered to accommodate the respective culverts.To prepare the optimization model, an objective function has been formulated to cover all aforementioned costs. The optimization model involved all structural and hydraulic design constraints. The established non-linear optimization model is solved by the modified Hooke and Jeeves direct search approach. A computer program is developed to handle the aimed solution.The following categories of analyses have been considered:1. Cost as a function of discharge (for the different selected lengths).2. Cost as a function of length (for the different selected discharges).3. Number of vents as a function of discharge (for the different selected lengths).4. Number of vents as a function of length (for the different selected discharges).5. Dimensions of the culvert as a function of .....

The capillary tube is a common expansion device used in small sized refrigeration and air-conditioning systems and whose function is to reduce the high pressure in the condenser to low pressure in the evaporator and therefore drops the temperature of the refrigerant.
The main focus lies on the analysis of the refrigerant flow behavior in the capillary tube, including pressure drop, temperature and quality distribution along the tube by using a commercial code FLUENT V.6 for the simulation.
The numerical results are compared with experimental results from internet web site and show a good agreement. It shows the capability of the code to simulate the flow and phase change in the capillary tube.

In this paper Frequency-Hopped Orthogonal Frequency Division Multiple Access (FH-OFDMA) system is considered. The performance of different Extending Quadratic Congruence (EQC) orthogonal hopping code patterns is examined in relation to OFDM transmission. The performance is evaluated in terms of Bit Error Rate (BER) in white Gaussian noise and Rayleigh fading. Multi-user interference (MUI) is eliminated and symbol recovery is guaranteed. The performance of FH-OFDMA system shows low bit error rate and good correlation properties under the circumference of the assumed channel.

The drop-cone method, in which a 30° cone of mass 80 g is allowed to penetrate into a soil sample at any moisture contents, was used to determine the plastic limit for more than 160 natural samples representing a wide range of soil type with different values of liquid limit ranging from 25 to 75%.Using the drop-cone penetrometer device, the moisture content corresponding at any penetration value is sufficient to generate the empirical formula to determine the plastic limit. The calculated values, from formula or chart, were close to the exact, tested, values. Hence, it is suggested to redefine the plastic limit as, the difference between the moisture content corresponding to the penetration of the drop-cone of 20 mm and that corresponding to any penetration divided by plastic factor corresponding to that penetration in which the product then subtracted from the liquid limit. The plastic factor can be determined from plastic factor-penetration curve. The advantages of such new method is that the test is more closely related to soil behaviour, less subjective, at least as reproducible as the Casagrande test and may be carried out simultaneously with the liquid limit test.

The aim of the present study is to represent a numerical modeling of thermal distortion and stress distribution of welded plate by using submerged arc welding .The study is carried out using existing software, which is the ANSYS package. The distortion of welded plate is found to be a nonlinear problem in geometry and material; therefore, the finite element solution is based upon the thermo-elasto-plastic and large deflection theory. The present work is an extension to a previous experimental work, where heat absorption paste (bentonite) was used to reduce distortion in welded plate, as a result of high local heating during welding process. The numerical results of distortion give reasonable indication with the distortion observed by Al-Dhamin [1]. Different rates of heat absorption are considered in this study over different area of cooling. The results show that, the distortion may be reduced significantly, by using cooling technique more efficient than the bentonite, as, using the cooling liquid of nitrogen. In this work, the optimum ratio of the cooling zone width (a) to the welded plate width (b), so as to minimize the distortion, is found equal to (a/b=0.2) for the plate at cooling temperature, equal to (30Cº, 0Cº) and (a/b=0.4) for plate with cooling temperature equal to (-30Cº). One of the experimental applications of this study is the formulation by heat source, as it is done with the structure of ships.

The aim of this paper is to investigate the effect of flat Rayleigh fading channel on the performance of the OWDM (Orthogonal Wavelet Division Multiplexing) system. This scheme is shown to be overall quite similar to Orthogonal Frequency Division Multiplexing (OFDM), but with some interesting additional features and improved characteristics. The system performance is investigated for various Doppler frequencies for a channel. OWDM system is compared with OFDM. A detailed analysis of the system's implementation complexity is also reported.

The elastic critical load for a non-prismatic member is derived using the equations of the modified stability functions for a wide range of tapering ratio having rectangular and square cross sectional shapes bent about the major axis and any other solid cross sectional shape tapered in depth only. The effective length of members at any support conditions is obtained with respect to the hinged-hinged supports. The elastic critical load is obtained by using the finite elements method as an approximate solution to verify the results. This study can be used as a reference to obtain the elastic critical load and effective length of columns.

To date, the majority of previous numerical models of the decay of thermal stratification during relaxation time in liquid tanks have ignored the effects of the wall of the storage tank. In this study, a one-dimensional, time dependent mathematical model to predict the degradation of heat in stratified thermocline liquid tank during relaxation periods (i.e. in the absence of external flow) for both cold and hot storage has been developed and tested. The model analyzes the interaction between the liquid inside the tank with its walls by including the effects of heat transfer by convection and conduction through the tank wall.The numerical simulations have been compared with experimental measurements of water tank. Data were taken on tank fitted with various horizontal porous baffles configuration (including location, number and materials of the porous baffles) and for various initial temperature distributions (stratified and isothermal conditions).The predicated profiles have been found close to those obtained experimentally especially at the top of the tank. It is found that the walls of the container can have a strong effect in destroying the thermocline. Temperature variation is found to be negligible in the horizontal direction except in the regions very near to the tank wall. Experiments show that better thermal stratification can be obtained by using horizontal porous baffles. The gravel baffles is found to be more effective for enhancing thermal ....

In this paper, An-Non destructive test technique was used to study the change of depth and Location of transverse cracks on the vibration characteristics of the rotating shafts. Firstly, It measured the natural frequencies of the rotating shaft are measured before renewing cracks with different dimensions and depths from the bearing of the rotating shaft. And by knowing the Speed of the Shaft, Then by using (Vibration analyzer B & K type 2515) to analyze the vibrational characteristics during the rotation and compare it with mathematical analysis using the method of mounting the rotating shaft. Secondly, a crack of a certain depth and dimension away from the rotating shaft bearing was made. The measurements of the natural free vibration due to the presence of the crack were carried out. The study took into consideration the diameter and the length of the rotating shaft. The practical results showed a decrease in the natural frequencies of the rotating shaft when the crack was present. This decrease was more when the crack was located in areas near the bearing than was located away from the bearing.