Wasit Journal of Engineering Sciences

Abstract: Noise pollution is one of the most problems caused by internal combustion engines. In this study, the reduction of noise by changing the orifice shapes and inserting tape is experimentally investigation. The effect of orifice shape on noise reduction of silencer is presented. The calculation of transmission losses and transmission coefficient of noise for different shapes of orifice by using MATLAB program is obtained. In addition, the frequency for maximum and minimum losses is obtained. The results showed that the use of the square orifice and helical tape were better options to reduce the noise in the silencer.

Abstract: Electrical discharge machining (EDM) is a non-traditional process that uses the electrical spark discharge to machine electrically conducting materials for geometrically complex shapes or hard materials. In the current work, cupper and brass were used as the electrode material, and AISI H13 steel as the workpiece. Different input parameters were investigated namely: 20, 30, 40 A current, 50, 100, 150 μs pulse on time, and 1, 3, 6 mm gap. The workpiece thickness was fixed to 4 mm and the pulse off time was 25 μs. All EDM experiments were carried out in diesel oil and the voltage was 140 V. The results showed that the electrode wear decreased with increasing the pulse on time and gap and increased with increasing current for copper and brass electrode. The optimal conditions for minimum tool wear were: pulse on time 150 μs, current 20 A, and gap 6 mm for copper and brass electrodes. Electrode wear is minimum for copper at all parameter values compared to brass electrode.

Abstract: Projects selection is a significant problem. However, regularly challenging task. It is difficult because there is typically more than one measurement of the effects on all projects, particularly when there are multiple decision-makers. In this paper, the authors consider a tangible presentation of projects choosing for a different number of projects through an experts opinions by a group decision-making method called TZOPSEIS (Technique for Order Preference by Similarity to an Ideal Solution). This method is characterized by its ability to measure the relative performance for each alternative in a simple mathematical form. Four criteria have been deliberated to select the finest one among five projects and rank them. The proposed manner is used in a case study in the Iraqi environment which is analyzed from diverse directions of vision to evaluate and select the best small project.

Abstract: Recently natural coagulants are a consistently expanded; plants extracted coagulant which may be adopted in the coagulation-flocculation activity of textile wastewater treatment for reduction concentration of turbidity and total suspended solids. In this study, the possibility of a combination between chemical coagulant (alum) and natural plant coagulant (Capparis Spinosa) in excluding turbidity and total suspended solids from textile wastewater has been studied. A set of experiments were implemented for verifying the turbidity and TSS removal efficiency using alum and powder extracted from Capparis Spinosa plant separately. A combined dosage consisted of chemical coagulant (alum) dosages (10, 20, 30 and 40 mg/l) with natural coagulant dosages (10, 20, 30 and 40 mg/l) in order to detect the optimum combined percentage of both coagulants (alum and Capparis Spinosa) that produces higher removal efficiencies for both turbidity and TSS. The study found the activity of removal for both turbidity and total suspended solids increased in high performance when mixing is occurred between natural coagulant (Capparis Spinosa) and chemical coagulant (Alum). The results illustrate that the combination of 20 mg/l alum with 30 mg/l Capparis Spinosa made 99% turbidity removal and the combination of 30 mg/l alum with 30 mg/l Capparis Spinosa made 98% TSS removal.

Abstract: Mankind is currently living in the age of industrialization and development in all its forms and manifestations because of its effects in all everyday life. This is because the technology has left a clear impact on human thoughts in general and architectural thoughts in particular. As the architecture is the embodiment of the thought of society that was produced, so the architecture must also be affected. This can be seen in the transition from the stone building and the limited narrow spaces to New Horizons across time. Thus the obvious diversity of forms, the widening of spaces and their sequencing in unlimited forms. With the advent of the Industrial Revolution At the beginning of the twentieth century, its invasion of the world and its profound influence in various fields and among the architecture has reduced the focus on traditional forms design language and fantasy became more realistic by using computer modeling, its impact on architecture swept through the new forms of industrialization and the folding of cognitive and spatial distances, thus demonstrating uniqueness, creativity and expressing the self-identity and the time features that . It was born, from here the problem of research has arisen, which provides for "inadequate knowledge about the role of industrialization and mass production and its impact on producing Architectural forms that are unique, creative. This corresponds to the changes in human need but in contrary to the classical architecture language that came from. The research follows a series of actions to solve the research problem after the formula of the research hypothesis became as "The process of manufacturing and digital production affects the process of producing architectural forms positively or passively depending on nature, function, and the extent of repetition of the project". The most important conclusions and recommendations that demonstrated the architects quest to take advantage of all the possibilities of industrialization and the short-time production and increase the creative imagination of the designer with regard to architectural design is to create new languages and vocabulary for the architectural formation that is suited to the spirit of the times, and the pattern of existing buildings and installations of all types and functions, and the way they perform these various functions, is changed.

Abstract: Weir is usually used in different hydraulic purposes, mainly for head discharge-water relationship in channels. In this research, the flow has been carried out over the side of spillway using three cases of crest inclination by means of increasing one side of the weir a half centimeter each time with constant crest length equal to 15 cm. This means that the angle θ equals to (1.91˚, 3.82˚ and 5.71˚) respectively towards of the flow and is opposite to the flow with decreasing a half centimeter. Also in case of the breadth is horizontal (θ=0), seven cases have been tested. It is known that the greater amount of discharge occurs when the breadth is horizontal (θ=0). In case of the inclination of the weir is inclined opposite to the flow direction, the discharge is greater than that of which the weir inclined towards the flow direction for all cases of inclination. The greater discharge was obtained when decreasing the angle, which is opposite to the flow direction. The amount of discharge over the side of weir decreases by increasing the angle of the slope opposite to the direction of the flow and become more decreasing in case the inclination of side weir towards the flow. In case of increasing the angle of inclination in flow direction, the amount of discharge over side weir will be decreased. The effect of Froude number has also studied with the discharge coefficient and found that, they are proportionally related to each other. Also the water surface profile along the side spillway weir is studied and taken under consideration theoretically and experimentally in this research.

Abstract: the study adopted samples from Tigris river shoulders ,which has been subjected to such collapses and cracks. After testing and investigation it was found the soil is formed from river deposits , which can be classified as fine sand soil . It is known that many of the collapses that occurs in the sides of rivers are due to the influence of shear forces . A different of diameters coarse aggregates columns and aggregates sizes used in this study are tested by direct shear test.

The main objective of this research to increase the coefficient of friction between the soil particles in the test specimen by adding the coarse aggregate columns to the fine sand soil, In this regard the least void ratio was found as a beneficial index that relates with critical state of friction angle independent on soil gradation. The relations between critical state or high friction angles of the mixture with lower void ratio were determined as a function of addition pressure. The relationships could be useful to determination the strength parameters of (sand gravel mixtures).

Abstract: the study adopted samples from Tigris river shoulders ,which has been subjected to such collapses and cracks. After testing and investigation it was found the soil is formed from river deposits , which can be classified as fine sand soil . It is known that many of the collapses that occurs in the sides of rivers are due to the influence of shear forces . A different of diameters coarse aggregates columns and aggregates sizes used in this study are tested by direct shear test.

The main objective of this research to increase the coefficient of friction between the soil particles in the test specimen by adding the coarse aggregate columns to the fine sand soil, In this regard the least void ratio was found as a beneficial index that relates with critical state of friction angle independent on soil gradation. The relations between critical state or high friction angles of the mixture with lower void ratio were determined as a function of addition pressure. The relationships could be useful to determination the strength parameters of (sand gravel mixtures).