KUFA JOURNAL OF ENGINEERING

The problem addressed by this research is how to increase the production of cement mills in the Kufa cement plant when changed the pattern of production and what are the reasons that led to the reduction of productivity. After investigating the research problem, it is found that the change in the pattern of production has led to a change in the size of clinker granules from (15-50 mm) in the case of ordinary cement to (5-15 mm) in the case of sulphate resistant cement. As a result, a change in the behaviour of clinker movement would occur inside the cement mill, that is, the fineness clinker penetrates the grinding balls, and thus reducing the grinding efficiency of the balls, with a diameter of 100 mm, and then productivity. The results of this research have shown that the waiver of balls with a diameter of 100 mm and compensation of smaller balls while maintaining the same weight of the charge led to the increase of the total surface area of the balls increasing as such productivity from 60 t/h to 85 t/h. In conclusion, it appeared that the findings of this study match those of Cleary (2009), which state that the potential energy retained by small balls is greater than that retained by large ones. Thus, the efficiency of the grinding will be increased. In addition, the reduction of the diameter of the balls will prevent the penetration of the clinker between the balls unless they are crushed into soft granules. This will maximize benefit from the kinetic and potential energy of the grinding balls.

Polyvinyl alcohol (PVA) defines as a self-curing agent when it forms films prevent evaporation water required to hydration. In this study was found the effect of self-curing factor on some mechanical properties is studied by adding of PVA solution to cement ratio (P/C) with varying conditions of curing. The PVA dissolved in water from 1% by weight of cement. It was seen that PVA could service by self- curing through providing increase strength compare with traditional curing. The results showed increased percentages of flexural, tensile and compressive strength of cement mortars with PVA as self-curing agent under dry condition for 28 days were 62%, 101%and 1.5% respectably to compare with self-curing for cement mortars composite modified with PVA as curing agent under wet curing conditions as soon as cement mortars composite modified without PVA were 110%, 5%and14.5% respectably in dry condition also 48 %, 55%and 41% in wet curing conditions respectably. The use of Fourier Transforms Infrared (FTIR) spectra and techniques like scanning electron microscope (SEM) is very significant to show the impacts of the existence of PVA as water-soluble polymer in the fine structure of modified cement mortar by polymers.

In this study, the peak discharges of Adhaim River were plotted against their hydrologic years. Two probability distributions and five plotting positions formulas were fitted to the annual maximum discharges AMD. The performances of the probability distributions with plotting position formulas were evaluated using the coefficients of determination R2, root mean square errors RMSE, Mean Absolute Percent Error MAPE, and absolute differences between predicted and observed discharges. The annual maximum discharges of Adhaim River vary in magnitude from 111 to 3520 m3/sec for record periods. The mean of annual maximum discharges 753 m3/sec. The Lognormal LN and Log-Person type III LP3 distributions have the highest R2 using Weibull plotting position formula WPP of 0.992 and 0.989, respectively. The LN had minimum RMSE and MAPE of 69.13 and 7.3%, respectively, when conformed with California plotting position CPP. The LP3 had minimum RMSE and MAPE of 93.6 and 6.5% respectively when conformed with Chegadayev plotting position CHPP. The minimum absolute differences at return periods of 25, 50,100, and 200 years were obtained when LN conformed with Hazen plotting position HPP and when LP3 conformed with CPP.

In this paper, the finite element ANSYS software was used to study the seismic behavior of cylindrical fuel storage tanks in west of Basra governorate. Single and group tanks are analyzed under free vibration (empty and full tanks) and under the El-Centro earthquake component for an impulsive case and full tank with fuel. The interaction between tanks wall and internal fuel was considered. The study includes Hoop forces, bending moment, shear force, horizontal displacement and hydrodynamic pressure. Also, the reflection point for bending moment and shear force for tank wall is estimated.

This study shows that the response of a single tank is larger than group tanks, and the hoop force decreases about (10-17) %, while the pressure and displacement decrease about (5-10) %, and the shear force and bending moment are decreased about (37-42) %. The increase in tank diameter leads to increase the response of tank. The Time has come to the understanding that the fixed support of tank is more stable than hinge support.

To investigate the reaction forces produced by the change in momentum of a water jet, an experimental and computational fluid dynamics (CFD) study are carried out. In the experiment, the water jet forces on a test horizontal hemispherical cup are measured. ANSYS CFX simulation code is used to provide a 3D CFD simulation of a circular cross section water jet released from a nozzle and moves upward in the air before striking a horizontal hemispherical cup and a flat plate. The progress in the CFD simulation within the last decade make it possible to analyze and visualize the flow pattern of complex multiphase free surface fluid flow. The simulated forces of the vertical water jet against a horizontal hemispherical cup using ANSYS CFX code are compared with the experimental forces generated by the water jet as it strikes a hemispherical cup. A good agreement is found in the CFD results compared with the experimental results. 21.649 % was the maximum percent difference recorded at 0.245 kg/sec flowrate and 0.484 % was the minimum percent difference at 0.368 kg/sec flowrate.

The tendency to build cable arch stayed bridges is increasing due to their aesthetic appearance and efficient performance. Due to overloading or time passing, they may face deformation thus they are required to be reshaped. For the same explanations the cables could undergo high tension and some others face slack, in order to keep the bridge safe in terms of stress failure, the redistribution of internal force of cables is essential. Pragmatically, the displacement restoring and the force redistribution are simultaneously necessary, since both issues arise together. This paper deals with simultaneous control of nodal displacement and internal force of cable theoretically by MATLAB Program and experimentally of a linear and a geometrically nonlinear model. The paper also shows that how the technique of adjustment response to control linear and geometrically nonlinear structures. It was determined that the technique was pragmatic and effectual for linear structures. While it was not very accurate for geometrically nonlinear structures, since more than one iteration was required to get the target.

This paper presents thermal and hydrodynamic behaviours of some selected food supplements in a modelled oesophagus. These food supplements are orange juice and water melon juice while chyme was used as the base food supplement for comparison. Numerical method was adopted using Solid Works 2014 and Ansys fluent as working tools.

Increase in geometrical trend in the demand for electrical energy, in addition to large interconnections, has increased the operational and structural complexities of modern power systems. Improved performance in modern power systems as well as enhanced reliability without sacrificing the integrity of the network at a minimum operating cost is, therefore, of great concern to power system utilities researchers and engineers. In addition, there has been a rapid development in the integration of renewable energy sources into the conventional power systems and various hybrid generating plants, in modern power systems, have emerged. In solving the EDP in modern power systems, due to the existence of non-convexity in the problem, the capability derived in the meta-heuristical-based methods have been extensively explored in recent times. This paper, therefore, presents a comprehensive review of various meta-heuristic approaches through which the solution to economic dispatch problems could be effectively provided.