DIYALA JOURNAL OF ENGINEERING SCIENCES

The aim of this work is to study the wear characteristics of different cast iron types which might be used as mould materials in glass blow molding. Wear testing rig was designed and developed to carry out the wear tests. Three types of gray cast iron with different chemical compositions were cast and heat treated, as well as samples taken (for comparison) from another two existing mould already being in use.Samples for wear testing were taken from the prepared materials and abraded against an automobile friction brake pads. Sliding velocity, friction pressure and contact time were taken as test variables. Weight loss of the tested samples was measured after conducting the wear tests at 600 & 800 0C. Cast iron with (2.98% C, 5.117% Si, and 1.39% Cu) showedthe highest hardness in its as cast condition compared to the other types. It showed the best wear resistance after heat treatment (stress relief annealing).Results also showed that some of the tested materials gave a good wear resistance at low temperature (up to 600 0C) but they lost their resistance at high temperature (up to 800 0C). It was concluded that hardness is not the only parameter that controls the wear resistance at high temperature.

Hamming code is an efficient error detection and correction technique which can be used to detect single and burst errors, and correct errors. In communication system information data transferred from source to destination by channel, which maybe corrupted due to a noise. So to find original information we use Hamming code.In this paper, we have described how we can generate 7 redundancy bit for 64 bit information data. These redundancy bits are to be interspersed at the bit positions (n = 1, 2, 4, 8, 16,32 and64) of the original data bits, soto transmit 64 bit information data we need 7 redundancy bit generated by even parity check method to make 71 bit data string. At the destination receiver point, we receive 71 bit data, this receives data may be corrupted due to noise. In Hamming technique the receiver will decided if data havean error or not, so if it detected the error it will find the position of the error bit and corrects it. This paper presents the design of the transmitterand the receiver with Hamming code redundancy technique using VHDL. The Xilinx ISE 10.1 Simulator was used for simulating VHDL code for both the transmitter and receiver sides

A finite element method is practical and applicable for many fields including for geotechnical engineering structures. Seepage through earth dam is difficult to analyze especially dams with multiple zones. The problem becomes complex if it requires deformation analysis taking into account seismic conditions. Therefore, finite element is the best tool for analyzing seepage flow in an earth filldam. The main objective of the paper is to simulate the seepage flow through an earth filldam. Hassan Kanosh Dam which is located in the north eastern part of Iraq is chosen as a case study. There are three periods in the life of a dam which may be critical from the standpoint of shear failure and which must be analyzed; during construction condition, full reservoir condition, and rapid drawdown condition. The program SIGMA/W which is a finite element software coupled with SEEP/W, (another GEO-SLOPE software product) to analyze the dam. The stability analysis performed showed that all parts of the dam are safe within the prescribed rang of factors of safety for the possible loading and operation cases. It is recommended, however, that close control of the quality of the works during construction must be maintained to realize the shearing strengths necessary to fulfillthe assumed strength and even more. It is recommended to check routinely the foundation conditions during excavation to realize the same end results

The grounding transformer is one of most important equipment in power energy system.This paper describes the modeling ofzig-zag grounding transformer wound core type with varying degrees of complexity.In this paper, the Finite Element model (FEM) of zig-zag grounding transformer with non-linear magnetic characteristic for iron core is built using ANSYS software electromagnetic package.A numerical method, based on Finite Element Analysis (FEA), is presented for computing the zero-sequence impedance of grounding transformer. The analysis method is based on the two dimensions (2D) model and this model was solved by using the magnetic vector potential formulation (A).The main purpose of this paper is performing the modelingof the three-phase zig-zag grounding "wound core" transformer in 2D FEM for any capacity of transformer(100KVA-1000KVA)and the Finite Element techniques are used for the magnetic field analysis to evaluate the magnetic field and to determine their distribution at any region inside the core window and winding.Two types of analyses were performed, including static and transient analysis.The transient analysis in this workis simulated by direct coupling the 2D transformer model with external circuit (voltage sources) .The simulation results prove the analysis' correctness and validity, andthe result of zero-sequence impedance of grounding transformer is verified by comparison with experimental result. Those measured in the Diyala transformer factory once the grounding transformer has been built. A good agreement of the computational results with experimental result by using this FEM modelof zig-zag grounding transformer allowing us to know the transformer behavior before manufacturing them and, thus reducing the design time and cost.

The grounding transformer is one of most important equipment in power energy system.This paper describes the modeling ofzig-zag grounding transformer wound core type with varying degrees of complexity.In this paper, the Finite Element model (FEM) of zig-zag grounding transformer with non-linear magnetic characteristic for iron core is built using ANSYS software electromagnetic package.A numerical method, based on Finite Element Analysis (FEA), is presented for computing the zero-sequence impedance of grounding transformer. The analysis method is based on the two dimensions (2D) model and this model was solved by using the magnetic vector potential formulation (A).The main purpose of this paper is performing the modelingof the three-phase zig-zag grounding "wound core" transformer in 2D FEM for any capacity of transformer(100KVA-1000KVA)and the Finite Element techniques are used for the magnetic field analysis to evaluate the magnetic field and to determine their distribution at any region inside the core window and winding.Two types of analyses were performed, including static and transient analysis.The transient analysis in this workis simulated by direct coupling the 2D transformer model with external circuit (voltage sources) .The simulation results prove the analysis' correctness and validity, andthe result of zero-sequence impedance of grounding transformer is verified by comparison with experimental result. Those measured in the Diyala transformer factory once the grounding transformer has been built. A good agreement of the computational results with experimental result by using this FEM modelof zig-zag grounding transformer allowing us to know the transformer behavior before manufacturing them and, thus reducing the design time and cost.

There are two main types of cathodic protection systems: galvanic and impressed current. In this research, the effect of coatings on impressed current cathodic protection was studied. The selection of coating process for a specific application depends on several factors including the corrosion resistance that are required, the anticipated lifetime of the coated material and environmental considerations. When using cathodic protection on coated pipelines, the problems that exist if the coating disbands (loses adhesion) must be considered. Many in the oil steel pipeline industry assume cathodic protection will solve their external corrosion problems without truly understanding the relationship between the epoxy-coating and cathodic protection.Most external corrosion on oil steel pipelines is caused by disbanded epoxy-coating that shield cathodic protection. This paper will discuss the differences in cathodic protection of oil steel pipeline that coating and not coating and how cathodic protection works with these coatings (wear used epoxy(G-5470), (G-5471) and (G-5472), three types component epoxy system resistance to acid and chemical from modern paints industrials Company (in Iraq)). The aqueous corrosion properties of the coated samples in3.5 wt % NaCl solution were studied by Tafel extrapolation measurements.

Using pulse compression at the receiver side of communication systems yields sidelobes around the mainlobe that permits the clutter to pass through it, and mask the desired signal.In this paper, a proposed Genetic Algorithm (GA) is used to generate optimum binary phase coded signals with minimum Peak SidelobeLevel (PSL) as criteria. It is shown that, when programmed genetic algorithm, the generated codes up to length 105 bits, withminimum peak sidelobelevel vary from (1-5).Then the comparison of sample of the codes that generated by this algorithm with unoptimum code has the same length to obtain the effectiveness of the generated codes. It is found that the codes produced from the genetic algorithm has high efficient by reduction the peak of sidelobe level and merit factor than other codes. Test the Doppler effects of these codes by plotting the ambiguity function and calculating the value of peak sidelobe Level (PSL) and the properties of different Doppler shifts at (0.0, 0.05, 0.1 and 0.15) are done in this paper. It found that the performance of the optimum binary phase coded signals which generated by genetic algorithm that better than unoptimum codes when the Doppler shifts was increased.

Tilted Fiber Bragg Gratings (TFBGs) are designed and implemented at the 1550 nm communication windowinInstitute of Optoelectronic Technology, China Jiliang University, Hangzhou, China. They are experimentally demonstrated to work as high sensitive temperature sensingelement. The tilted fiber Bragg gratings of 10 mm were written on the core of 7-cm and 26-cm hydrogen loaded side hole fibers using 244 nm frequency doubled 488 nm Argon ion laser based on phase mask technique. The transmission spectrum of the first TFBG sensing element showed two resonant dips at 1579.614 nm and 1582.502 nm respectively. The transmission spectrum of the second TFBG sensing element showed two resonant dips at 1579.108 nm and 1580.304 nm. The achieved sensitivity is about 10 pm / °C. To thebestof our knowledge our finding regarding setup with low cost is very close to the performance of other types of Fiber Bragg Gratings (FBGs)(1)

Through this paper, the optimized cost was estimated to develop a new hybrid system contains a combination of various alternative energy resources. Designing any new project requires an estimation for the minimum amount of money required for initiating it as well as the cost of operations when it is in running process. For any electric power project, the cost of electricity is very significant because it totally affects the end user or the consumer. By using HOMER simulator, these parameters were analyzed. The project was implemented in Hyderabad City, located in southern Pakistan. This city is gifted many natural resources that can produce a considerable amount of power energy for the region.This paper, highlights the average amount of all these resources that can be achieved throughout the year

The ethylene production is regarded one of the most significant issues for chemical industries and improving its production operation can bring several benefits. Thus, the market demand for ethylene production has accelerated the improvement of a more rigorous and reliable thermal cracking model of such process. In the present study, developing a rigorous mathematical model for an industrial naphtha cracker is investigated based on experimental data combining with a kinetic model describes the coke formation on the internal reactor tubes.The best kinetic model obtained is applied for predicting the products yield, the gas temperature and the optimal temperature profiles along the reactor to maximize the profit of the process. The influence of process factors on the optimal solutions (mainly, coiloutlet temperature (COT), steam to naphtha ratio (S/N) and feed flow rate on the product yields have also been discussed here, and new results of the reactor with the optimal cost and temperature profile are obtained. Modeling, simulation and optimal design via optimization of the industrial thermal cracking reactor has been carried out by gPROMS software. The optimization problems are solved employing a Successive Quadratic Programming (SQP) method formulated as a Non-Linear Programming (NLP) problem.

Aluminum matrix composite is most important materials used in various industries because of its good properties such as wear resistance, low density, and high resistance to weight ratio. In this paper, Metal matrix composites (MMCs) of the base alloy (Al-6061) and (Al-5086) reinforced by silica particles (SiO2) (1.5, 3, and 4.5 wt%) with particles size (150 µm) was prepared by stir casting using vortex technique, silica particles (SiO2) are added to the molten and then stirred the melt by electrical mixer stir to work the vortex and then pour the mixture molten into cylindrical mold and then was cutting and preparation of samples for examination and testing of wear, hardness, density and study the microstructure of the samples and the comparison between them. Results show from this study that the wear resistance of Al matrix composite its improvement due to addition of silica particles (SiO2) as compared with basis alloys, (Al-5086) matrix composite has higher wear resistance rather than (Al-6061) matrix composite. The higher wear resistance at added the 4.5 wt.% of silica (SiO2). The addition of silica particles in proportions above has contributed to the improvement of hardness which is reflected in improved wear resistance, and that this improvement in properties increases with the proportion of silica particles added to alloys base. As for the properties of density, decreases the density of Al-matrix composites as compared with base alloys with low proportion when added the silica particles (SiO2).

This research is aimed to produce Zn-4Al alloys by using powder metallurgy technique. Zinc and aluminum powders were thoroughly mixed to obtain Zn-4 wt% Al. Alumina powder with different weight percents 2, 3 and 4 then added to Zn-4 wt% Al mixture. Careful mixings were applied to guarantee homogeneous distribution of alumina in the zinc-aluminum powder mixture. Cold pressings at 6.5 t using cylindrical die were done. Sintering of samples at 335 ­oC for a period of 1 hr using argon gas as an inert gas were made. Grinding, polishing and etching were applied to the sintered samples in order to study the microstructure and hardness. Green density, true density, X-ray diffraction and wear resistance were also investigated. Results obtained showed that increasing the volume fraction of alumina increased the green density after pressing while the true density increased after sintering as compare with green density. Both the size of porosity and its percentage decrease because the formation of hard phases from zinc and aluminum. This is lead to increase the Vickers hardness and enhance the wear resistance of samples due to the formation of second phase of Al4Zn6 and also to the presence of alumina powder.