KUFA JOURNAL OF ENGINEERING

A two dimensional turbulence (SST, k-) model is used to predict the distribution of air velocity and temperature in a 2-D office room, containing one person and office furniture for two ventilation conditions. This study use a commercial CFD code FLUENT (version 6.3) for solving the Navier Stocks, energy and turbulence equations using finite volume techniques. The results were presented as velocity vectors with quantitative velocity and temperature distribution. The result can be divided into two parts, First part compared with published result and gives good theoretical agreement, the second part was taken at boundary conditions (Vin, Tin and Twall) according to the Iraqi environmental condition depend on the Iraqi cods of cooling 2012.

A new expression for estimating the ultimate shear strength of steel fibers reinforced high strength concrete (SFRHSC) beams strengthened with CFRP strips based on previous researches is proposed in this research. The proposed expression covers different characteristics and principal parameters such as concrete compressive strength, shear span to effective depth ratio, volume fraction of steel fibers, CFRP amount and distribution, CFRP stiffness, deep beam effect, as well as the end anchorage state of the CFRP strips with the beam. A comparison between computed values and experimentally observed values (with a low COV of about 3.58 %) shows the validation of the proposed theoretical treatment.

This paper presented nonlinear finite element analysis to predict the load deflection behavior of circular cell cofferdam under lateral load by using ANSYS (Analysis System) (version 12.1) computer program. Eight-node solid element (SOLID 45) has been used to model filling soil, and the same element by using overlap and glue technique to model steel sheet pile of cofferdam. The bond between steel sheet pile and filling soil has been modeled by using nodes merge.

Integrated advanced wastewater treatment provides important fundamental solutions to problems associated with water scarcity prevailing in arid and semi arid climatic regions. This was accomplished through treated water with specific specification and characteristics suitable to be used for agricultural, domestic, and industrial purposes. This study is concerned with the use of genetic algorithm procedure for the optimum design of integrated advance wastewater treatment units, with their various types and characteristics. The aim of optimum wastewater treatment units design is to attain optimum values of certain pre defined objective function. Based on the results of applying genetic algorithm on activated carbon treatment plant, it was found that the optimum values of empty bed contact time, dose of activated carbon, diameter of contractor, and loading rate of multiple hearth furnaces are 10min, 25mg/l, 2.4m, and 30 m/min, respectively

Bearing capacity of soil is an important factor in designing circular footing. It is directly related to foundation dimensions and consequently its performance. The calculations for obtaining the bearing capacity of a soil needs many varying parameters, for example soil type, depth of foundation, unit weight of soil, etc. In this work, the comparison between the values of bearing capacity of circular footing on gypseous soil before and after improvement determined by two different methods, the first method using compacted cement dust (Case1). The improvement were performed by making trench under the footing filled with compacted cement dust (at its optimum moisture content) at three depths [(Depth of trench, D =Width of trench, B =2 * the radius of footing R); (D=2B=4R) ; (D=3B=6R)], the trench had the same footing Dimensions, The second method is reinforcing gypseous soil with biaxial geogrids (Case2) have been shown to be an effective method for improving the ultimate bearing capacity of granular soils.

In this paper a parameter optimization method using a neural network is suggested for finding the optimum control gains of a proportional deferential (PD) controller which it is used to control the excitation of the synchronous generator. In this work one PD controller and three D controllers has been used which it is mean five gains to be found which it is a very hard work to find it manually. The neural network has been used to automate the way in inding this gains which it was manually calculated until the desired plant output has been obtained. The controller gains which it is manually calculated has been compared with that calculated with neural network with MATLAB program and the performance has been simulated and compared.

Faults detection and isolation scheme on the bases of a hybrid Sliding Mode Observer (SMO) technique and fuzzy logic technique has been presented in this paper. The SMO technique was used for the fault detection purpose based on residual signal which represent the difference between output of the process and output of the model that used as a fault indicator, while the fuzzy logic technique was used as a fault isolator depending on fuzzy rules base and fuzzy membership functions. The performance of this hybrid technique is evaluated on a model of DC motor, the proposed scheme is illustrated on a Matlab/Simulink simulator and the results demonstrated a successful implementation of the proposed Fault Detection and Isolation FDI scheme.

Two-phase flow pattern, pressure drop, and void fraction in vertical transparent pipe of x m internal diameter and y m length is investigated experimentally. The rig is designed to achieve the measurements of pressure drop and void fraction for different combinations of phase superficial velocities such that the regimes encountered are bubbly, slug and annular, which required a wide range of water and air superficial velocities.

Field observations indicate that left turning vehicles at U-turn sections lead to a significantly bottleneck (congestion) at both origin and destination (opposing) roads. The bottlenecks have been observed in several U-turns such as Kufa –Najaf U-turn sections, Najaf –Karbala U-turn sections. It was found that left turn flow from U-turn leads to high congestion on both origin and destination roads. Therefore, field improvements have been done by the traffic policemen who create a temporary barrier from traffic plastic signs in order to protect left turning vehicles from through traffic in opposing direction. This study introduces new design for U-turn in order to protect both turning and through trafficto increase the level of performance. This design has been tested by using simulation model. The developed model (S-Paramics) has been calibrated using field data collected from Al-Najaf city. Then, the validation for the developed model has been implemented using another set of field data. Finally, the simulation model has been adopted to test the new design for U-turn. It was found that the new design gives higher capacity than the current design.

Due to construction costs and operational issues have been in this study to discuss how to strengthen the concrete columns. The results of previous studies on the construction of some structures earthquake-prone weakness reinforced concrete columns. The inside steel casings surrounding the columns is a modern technique used in many countries today for columns of rectangular and circular concrete. The advantages of this method is convenient, economical and easy. Reference model in this study is a column concrete without casing steel and the others concrete columns were wrapped casings steel to study the amount of retrofitting, and which has been approved changing the thickness of the cover steel are the main variable in this research. Were analyzed columns under the effect of axial force using the finite element method by using the program ANSYS (version 11). The results showed that increase the susceptibility of the inside steel casings bearing concrete columns of force inflicted by the largest of the main form without the steel casing, as well as to increase the thickness of the cover leads to increased endurance.