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Go to Editorial ManagerThe objective of the present paper is to evaluate the effects of the soil-structure interaction on the seismic evaluation in the building when a framed building is supported on raft foundation. Also the foundation-soil interaction effect has been considered by replacing it with equivalent springs. Nonlinear static pushover analyses of eight-storey reinforced concrete hospital building located at Delhi-India has been performed using the Capacity Spectrum Method of ATC-40. The deformations define the state of damage in the structure through three limit states of the NEHRP Guidelines and the FEMA-356 have been used to evaluate the performance level of the building for drift, the plastic hinge stage of the crack and shear under the condition of the fixed base and the effect of the soil-structure interaction. The performance of the building and individual components has been estimated for Design Basis Earthquake and Maximum Considered Earthquake. The weight of the slab was distributed as triangular and trapezoidal loads to the surrounding beams as per IS 456:2000. The weight of the brick masonry was distributed uniformly on the beams. The results show that the soil structure interaction has marked effect on the roof displacement, storey drift, design base shear, effective damping and crack pattern for beams and columns while there is a minor effect on the torsional behavior of the building. The building is more critical in the performance level when considering the soil flexibility.
In this paper, a finite element method program under domain loading and plain strain conditions is developed and applied in evaluation of the stress intensity factor in opening mode (K1) in two dimensions crack problems. Two types of crack problems analyzed and verified: first, cracked rotating disc made from bi-directional fiber reinforced material composite, second crack blade made from bi-directional fiber reinforced metal matrix composite. It is found that the finite element method under domain loading is a good tool for the analysis of composite material. The simulation is accurate in comparison with that obtained from extrapolation method. The stress intensity factor for fiber reinforced metal matrix composite is larger when obtained from fiber-reinforced material under same condition.
Continuously Variable Transmission (CVT) combines the efficiency of manual transmissions with the driving comfort of automatic transmissions while providing an infinite range of gear ratios, improved fuel economy, and enhanced acceleration performance. This study presents a comparative evaluation of CVT performance against manual and automatic transmissions in a parallel hybrid electric vehicle (HEV), focusing on fuel consumption and exhaust emissions. A baseline HEV model equipped with a CVT gearbox was selected from ADVISOR simulation software and subsequently modified by replacing the CVT with manual and automatic transmissions for comparison. Exhaust emissions, including catalytic converter pollutant reactions, were recorded for all configurations. Performance assessments were conducted using several global standard driving cycles to simulate real driving conditions. Results indicated that the CVT configuration achieved superior fuel economy and a significant reduction in exhaust emissions compared with manual and automatic transmissions. This improvement is attributed to the CVT’s effective control of speed ratio and overall transmission efficiency. The findings support the suitability of CVT gearboxes for urban hybrid vehicle applications due to their low fuel consumption and high efficiency in speed ratio control.
The efficiency of gas turbine units is highly affected by the variation of ambient temperature. Increasing the ambient temperature decreasing the efficiency of gas turbine. Cooling the inlet air to the compressor of the gas turbine units is an essential and economical technique for improving its efficiency. Al-Rumaila gas turbine power plant was located in Basrah city, Iraq, which is characterized by its hot climates for more than six months during the year. A novel upstream inlet air cooling system was applied and tested for Rumaila gas turbine power plant. This article represents a thermo-economic evaluation of applying upstream inlet air cooling system. The analysis is based on the test results for operating single unit of Rumaila gas turbine power plant using upstream inlet air system for cooling. The test was performed during July of 2019 for 90 minutes of operation period with ambient temperature of 45 °C. The evaluation analysis shows that, the power output increased from 217.71 MW to 250.11 MW during the period test with percentage increase in power by 15%. This increase in power output led to net economic gains is approximately 1000 $/h.
In this paper, the Weibull uni-axial and multi-axial distribution function for polyethylene pips under pressure loading were developed and analyzed taking account of residual stress. Tensile test was achieved to determine mechanical properties and the Weibull parameters. Experimental method using the hole- drilling strain-gage method was used to measure the residual stresses in PE pipe and compare with that obtained from numerical finite element method (FEM). The obtained results show that there is a convergence between uni-axial and multi-axial distribution function, but multi-axial distribution function give large values compared to uni-axial distribution function. It was observed that the residual stresses have influence on failure assessment diagram and causes translation from elastic-plastic failure to brittle failure.
This paper describes a study of traffic behavior at AL-Jumhoryia street in Baghdad city. The objective is to use simulation program OSPSM to evaluate the performance of on street parking. The first stage of this research project takes the basic measurements carried out using video camera. The basic measurements are traffic flow, operating speed, parking time, unparking time, gap, and average duration. The second stage of the simulation program OSPSM was to run it using all the observed input parameters to obtain some measures of effectiveness such as the delays caused to through vehicles, the delays caused to parked vehicles, reduction in capacity, turnover rate, Parking Index, Parking accumulation. The main conclusion to the performance of on street parking is that it is reasonable, the average delay of parked vehicles and through vehicles at AL-Jmahory street is accepted value.
A numerical simulation of the effect evaluation of heat loss and temperature distribution along the wellbore is performed, for two models, the first is an open hole (without perforation) and the other is a perforated vertical wellbore. In this study, the Computational Fluid Dynamics (CFD) software code ANSYS FLUENT 15.0 has been used, for simulate a model of 3-D turbulent flow with stander k-ϵ model. The results of this show that, increasing the heat losses leads to an increase in the temperature gradient, while the temperature gradient decreases with increasing inlet main velocity. Also, the temperature of the produced crude oil decreases with increasing the length of the wellbore.
AISI 4330 Low-alloy steel is good material for advanced application because of its properties including strength and longevity. However, performance may be modified with heat treatment procedures, include quenching and tempering. These processes can create residual stresses and retained austenite (RA), which have an effect on the metal's application. these factors influence fatigue life, dimensional stability, and fracture toughness of engineered components. uncontrolled residual stresses can reduce fatigue strength by up to 30%, while optimal retained austenite content (e.g., 5-10%) can enhance damage tolerance. This study focuses on residual stresses and retained austenite measurement in AISI 4330 low-alloy steel after heat treatment. including experimental and simulation methods. The review summarizes many scientific studies published between 2019 and 2024 and shows some main challenges. One challenge is the difference between experimental results (for example, from X-ray diffraction (XRD) and neutron (diffraction) and simulation results (especially using ANSYS software). Another challenge is that different methods for measuring retained austenite can give different results, which can change how we understand the steel's properties. The review also explains new progress in modeling heat treatment. This includes adding phase transformation models to finite element simulations. Future efforts should combine multiscale simulation, characterization, and machine learning to achieve predictive control over these properties in manufacturing.
This paper describes a study of traffic behavior at AL-Jumhoryia street in Baghdad city. The objective is to use simulation program OSPSM to evaluate the performance of on street parking. The first stage of this research project takes the basic measurements carried out using video camera. The basic measurements are traffic flow, operating speed, parking time, unparking time, gap, and average duration. The second stage of the simulation program OSPSM was to run it using all the observed input parameters to obtain some measures of effectiveness such as the delays caused to through vehicles, the delays caused to parked vehicles, reduction in capacity, turnover rate, Parking Index, Parking accumulation. The main conclusion to the performance of on street parking is that it is reasonable, the average delay of parked vehicles and through vehicles at AL-Jmahory street is accepted value.
This study aims to evaluate quality of groundwater samples in south of Basrah Province for industrial, construction and agricultural purposes. Groundwater samples were collected in summer season of the year 2015 from (29) wells located in different districts in Basrah province (Safwan, Zubair and Um- Qasir). The groundwater samples were analyzed for pH, electrical conductivity (EC), total dissolved solids (TDS) and other major ions. The chemical results indicate that the groundwater in the study area was unsuitable for industrial uses according to standard classification. Some other standard classification recommended that, the unsuitable groundwater could be used after treatment of some of its element while groundwater in study area may be used for construction purposes with suitable treatment of high ions concentration. After studying the factors that determine the suitability of groundwater for irrigation purpose such as pH, electrical conductivity, total dissolved solids, Sodium ratio(Na%) and sodium adsorption ratio (SAR). The groundwater in study area can be classify based on (EC) values, as unacceptable for irrigation except for very salt-tolerant plants and excellent drainage. According to other parameters like Na% and SAR , groundwater of the study area are classify as poor to very poor water and need for suitable treatment before using it.
This paper describes a study of traffic behavior at AL-Jumhoryia street in Baghdad city. The objective is to use simulation program OSPSM to evaluate the performance of on street parking. The first stage of this research project takes the basic measurements carried out using video camera. The basic measurements are traffic flow, operating speed, parking time, unparking time, gap, and average duration. The second stage of the simulation program OSPSM was to run it using all the observed input parameters to obtain some measures of effectiveness such as the delays caused to through vehicles, the delays caused to parked vehicles, reduction in capacity, turnover rate, Parking Index, Parking accumulation. The main conclusion to the performance of on street parking is that it is reasonable, the average delay of parked vehicles and through vehicles at AL-Jmahory street is accepted value.
This study focuses on the design and construction of an automated device for evaluating the scratch resistance of polymeric materials by measuring the force required to produce surface scratches and calculating the corresponding friction coefficient from device input–output data. The device was fabricated using locally available materials, with several components manufactured in local mechanical workshops. It comprises four main subsystems: mechanical components, scratching mechanism, electrical and electronic units, and an operating control program. The developed device offers the following specifications: normal load range of 0.1–325 N, sliding speed of 1–35 mm/s, tangential force measurement capacity of 0.1–294 N via a load cell, sample dimensions of 10–195 mm in length, 10–125 mm in width, and 0.25–50 mm in thickness, a maximum scratch length of 195 mm, and an adjustable indenter height ranging from 0.25 to 50 mm above the platform surface. Scratch testing and friction coefficient measurements were conducted on pure PMMA and PMMA reinforced with silicon dioxide (SiO₂) nanoparticles. Experimental results demonstrated increased scratch resistance and reduced friction coefficients with higher SiO₂ weight ratios. Additionally, the performance evaluation confirmed that the designed device is capable of accurately and rapidly measuring the tangential forces associated with scratching through a simple operational procedure.
In this paper, Weibull uni-axial and multi-axial distribution function is applied to evaluate the reliability of the fracture strength of rotating turbine rotor wheel manufactured from ceramic material and have inner surface crack. Three cases are considered, first taking only the effect of rotational stresses, second taking the effect of rotational and thermal stresses in ceramic disc, and third taking the effect of rotational and thermal loading in ceramic blade. It was found that there is a convergence between results gotten from uni-axial and multi-axial distribution function, but multi-axial distribution function give small large in values result compared to uni-axial distribution function. The expected values of rupture strength of ceramic blade is higher than of that of disc material, therefore the failure occurs in blade first than in disc material in service survival.
Exceptionally strong press-hardened steels (PHS) are significantly demanded in the automobile industry for satisfying the carbon neutrality criterion. Recent research attempts to produce advanced-ultrahigh-strength medium steels have resulted in a variety of alloying approaches, thermomechanical processing techniques, and microstructural modifications for these steel grades. It has been shown that adding microalloying components to standard Mn-B steels can refine the microstructure of PHS which leads to better mechanical properties such as hydrogen embrittlement resistance and other performance indicators for service. In this paper a general review about the effect of microstructure test on the mechanical behavior of Press Hardening Steel (PHS) where microstructure approaches have also demonstrated good potential for the mechanical characteristics of PHS steel, in line with need for new evaluation and discovery meantime, statistical data of the microstructural phases heavily influence the mechanical properties, microstructural image analysis is essential. The purpose of this paper is to know how the microstructure phases will effect on the strength and hardness of press hardening steel also the alloying elements adding impact on the microstructure formulation and mechanical features of PHS.
This paper describes a study of traffic behavior at AL-Jumhoryia street in Baghdad city. The objective is to use simulation program OSPSM to evaluate the performance of on street parking. The first stage of this research project takes the basic measurements carried out using video camera. The basic measurements are traffic flow, operating speed, parking time, unparking time, gap, and average duration. The second stage of the simulation program OSPSM was to run it using all the observed input parameters to obtain some measures of effectiveness such as the delays caused to through vehicles, the delays caused to parked vehicles, reduction in capacity, turnover rate, Parking Index, Parking accumulation. The main conclusion to the performance of on street parking is that it is reasonable, the average delay of parked vehicles and through vehicles at AL-Jmahory street is accepted value.
This paper describes a study of traffic behavior at AL-Jumhoryia street in Baghdad city. The objective is to use simulation program OSPSM to evaluate the performance of on street parking. The first stage of this research project takes the basic measurements carried out using video camera. The basic measurements are traffic flow, operating speed, parking time, unparking time, gap, and average duration. The second stage of the simulation program OSPSM was to run it using all the observed input parameters to obtain some measures of effectiveness such as the delays caused to through vehicles, the delays caused to parked vehicles, reduction in capacity, turnover rate, Parking Index, Parking accumulation. The main conclusion to the performance of on street parking is that it is reasonable, the average delay of parked vehicles and through vehicles at AL-Jmahory street is accepted value.
This study presents both experimental and theoretical investigations of an absorption refrigeration system using environmentally friendly working fluids, specifically the acetone–zinc bromide (Acetone/ZnBr₂) pair. The system was designed to operate under outdoor climatic conditions in Hilla City, Iraq, utilizing hot water as the heat source. Performance evaluation was carried out under various operating conditions, including changes in heat source, absorber, condenser, and evaporator temperatures. Experimental testing was conducted during September 2019. The results indicated that the coefficient of performance (COP) of the absorption cooling system ranged from 0.13 to 0.487, with an evaporator temperature drop of approximately 16 °C. Condensation and absorption temperatures remained below 41 °C, while the maximum driving water temperature reached 80 °C. A steady-state theoretical model was developed using the Engineering Equation Solver (EES) program, applying mass and energy balance equations to predict operating parameters such as temperature, pressure, and COP. Model predictions showed good agreement with the experimental measurements. Furthermore, the results confirmed that generator temperature has a significant influence on overall system performance.
This paper describes a study of traffic behavior at AL-Jumhoryia street in Baghdad city. The objective is to use simulation program OSPSM to evaluate the performance of on street parking. The first stage of this research project takes the basic measurements carried out using video camera. The basic measurements are traffic flow, operating speed, parking time, unparking time, gap, and average duration. The second stage of the simulation program OSPSM was to run it using all the observed input parameters to obtain some measures of effectiveness such as the delays caused to through vehicles, the delays caused to parked vehicles, reduction in capacity, turnover rate, Parking Index, Parking accumulation. The main conclusion to the performance of on street parking is that it is reasonable, the average delay of parked vehicles and through vehicles at AL-Jmahory street is accepted value.
In recent decades, the need for strengthening and repairing reinforced concrete structures has increasingly arisen. One common method is the use of concrete jackets. Slurry Infiltrated Fiber Concrete (SIFCON), a newly developed material, offers superior mechanical properties, making it a preferred choice for strengthening and repairing concrete structures. However, there is limited understanding of its bonding performance when used as an overlay on a Normal Strength Concrete (NSC) substrate. This study conducted a direct Shear Test (DST) to evaluate the bond performance using reinforced NSC cubes externally bonded with SIFCON jackets subjected to direct shear. Eighteen reinforced cubes were strengthened with various bonding systems to investigate how different factors affect the bond performance between the NSC substrate and SIFCON overlay. The parameters studied included surface preparation methods, binder types, jacket configurations, bonding conditions (fresh overlay on hardened substrate and hardened overlay on hardened substrate), dowel placement, and bonding mechanisms. The results show that using bonding agents significantly improved bond strength, with epoxy proving more effective than latex. Specimens prepared by chipping showed better bonding performance compared to those prepared through diamond cutting. Chipping increased bond strength by 8.91% to 13.84% over diamond cutting in the case of fresh SIFCON overlay on hardened substrate. Using dowels in the bonding systems also improved bond performance by 10.89% to 16.97%. Applying jackets to three sides instead of two increased the ultimate failure load by 31.76% when dowels were used in both the two-sided and three-sided strengthened samples, and by 35.45% in the absence of dowels in both types of strengthened specimens. The cast-in-situ specimens demonstrated superiority over those strengthened with precast jacket layers.
This research has been conducted in order to evaluate the compression index of Gypsiferous soil. A series of consolidation experimental tests with different percentage between 5% - 20% of gypsum added to the soil have been performed. From results. It had been seen that with increasing percentage of gypsum the compression index increased, with a maximum percentage of 30.4%.
The effect of different dosages of the high range water reducing admixture–additive- (HRWRA), the commercially polymeric material (Plastocrete-N), on the corrosion resistance of embedded steel in concrete exposed to chloride solution in the absence and presence of sulfate ions was studied. In the present study, four levels of polymeric material (Plastocrete-N) (0.125%, 0.250%, 0.375%, and 0.500% by weight of cement) were used to prepare HRWRA treated concrete. The concrete specimens exposed to chloride and chloride–sulfate solutions at concentrations of (3.5% NaCl and 5% Na2SO4), at ambient temperature. The electrochemical behavior of steel in both reference and HRWRA concretes was studied under the effect of corrosive environments using corrosion measurement systems such as: a) half – cell potentials measurement system and b) accelerated corrosion test system. The results showed that a longer time of corrosion initiation (180 day) observed with 0.500% HRWRA containing concrete compared to other different HRWRA percentage including the reference concrete. It was concluded that the use of 0.500% HRWRA provided superior protection to steel reinforcement in concrete that subjected to corrosive environments. Furthermore, the steel with 0.500% HRWRA was subjected to corrosion test by mass loss, it is evident that a reduction in mass loss by about 90.2% and 85.2% in both solutions, respectively.
This paper describes a study of traffic behavior at AL-Jumhoryia street in Baghdad city. The objective is to use simulation program OSPSM to evaluate the performance of on street parking. The first stage of this research project takes the basic measurements carried out using video camera. The basic measurements are traffic flow, operating speed, parking time, unparking time, gap, and average duration. The second stage of the simulation program OSPSM was to run it using all the observed input parameters to obtain some measures of effectiveness such as the delays caused to through vehicles, the delays caused to parked vehicles, reduction in capacity, turnover rate, Parking Index, Parking accumulation. The main conclusion to the performance of on street parking is that it is reasonable, the average delay of parked vehicles and through vehicles at AL-Jmahory street is accepted value.
This paper describes a study of traffic behavior at AL-Jumhoryia street in Baghdad city. The objective is to use simulation program OSPSM to evaluate the performance of on street parking. The first stage of this research project takes the basic measurements carried out using video camera. The basic measurements are traffic flow, operating speed, parking time, unparking time, gap, and average duration. The second stage of the simulation program OSPSM was to run it using all the observed input parameters to obtain some measures of effectiveness such as the delays caused to through vehicles, the delays caused to parked vehicles, reduction in capacity, turnover rate, Parking Index, Parking accumulation. The main conclusion to the performance of on street parking is that it is reasonable, the average delay of parked vehicles and through vehicles at AL-Jmahory street is accepted value.
Nanoparticles show mechanical, electrical, chemical and optical properties that are different and superior to bulk materials. In the present work, α-Alumina nanoparticles were synthesized using the nonorganic Sol-Gel method under controlled conditions. Because of the low cost of its raw materials, low manufacturing temperature and the high purity of the product, Sol-Gel method is the best in the manufacture of nanostructures like metal oxide nanoparticles. The precursor of the Sol-Gel process was aluminum nitrate with ethanol. The prepared nanopowder was evaluated by X-ray diffraction (XRD), scanning electron microscope (SEM), electron dispersive spectroscope (EDS) and Malvern Zetasize analyzer.
The foundation of soil is considered safe when the factor of safety against shear failure is adequate and the settlement of the foundation should be tolerable and does not cause any unacceptable damage for the structure. The ultimate bearing capacity is defined as the maximum pressure which may be applied to the soil without causing neither a shear failure nor large settlement. In this research the bearing capacity of the soil at diesel power plant project in Al-Diwaniyah city by plate bearing test. The soil has been tested in the field in the locations of four foundations for circular tanks of diameter of 17m. The load is applied to the plate in four increments. In each increment; the load stays static for 15 minutes according to ASTM D1194-94 specification. The results showed that the plate settlements of the soil under three tanks were within the permitted settlement. The allowable bearing capacity of soils under these tanks were (117, 137 and 137) kPa respectively. While, the soil under the fourth tank was soft and the plate settled approximately 30 mm immediately after applying the first increment of load. Therefore the soil is considered improper and recommendations are suggested to improve it.
This paper describes a study of traffic behavior at AL-Jumhoryia street in Baghdad city. The objective is to use simulation program OSPSM to evaluate the performance of on street parking. The first stage of this research project takes the basic measurements carried out using video camera. The basic measurements are traffic flow, operating speed, parking time, unparking time, gap, and average duration. The second stage of the simulation program OSPSM was to run it using all the observed input parameters to obtain some measures of effectiveness such as the delays caused to through vehicles, the delays caused to parked vehicles, reduction in capacity, turnover rate, Parking Index, Parking accumulation. The main conclusion to the performance of on street parking is that it is reasonable, the average delay of parked vehicles and through vehicles at AL-Jmahory street is accepted value.
The present work includes a study on the effect of loading rubber waste into cement mortar on the thermal and mechanical properties of a thermal insulator.The experimental work of the study included the preparation of ten models of 35 mm diameter and 5 mm thickness. Portland cement and natural sand were used as a matrix and rubber waste (extracted from the consumed tires) as a filler was added in weight percentages ( 5% ,10% ,15% ,20% ,25% ,30% ,35% ,40%,45% and 50%). Water was also used as a binder.Also, the experimental work included conducting a thermal conductivity test using Lee’s Disk method, and a hardness test using the Shore scale. The theoretical side included extraction of empirical equations, depending on the experimental results. The thermal conductivity equation was for two variables, temperature and mass fraction. While the hardness equation was for one variable, mass fraction. Theoretically determined heat capacity was extracted using the equations of the composites. Based on the empirical equations of thermal conductivity and hardness and using the technique of multi- objectives genetic algorithm, the optimum values of temperature and mass fraction were extracted, which achieve the best thermal insulation of the mortar. The results showed a significant decrease in thermal conductivity. The reduction in thermal conductivity was (90.3%) at 5% and reduced to (95.73%) at 50%. The specific heat capacity was increasing as the percentage of rubber waste increase. The results also indicated a decrease in hardness. The optimal value of thermal insulation was (0.02658 W/m 2 .ºC ) as a thermal conductivity and (58.07 N/m 2 ) as a hardness, at temperature (50°C) and mass fraction (27.764%) of rubber waste.
This paper describes a study of traffic behavior at AL-Jumhoryia street in Baghdad city. The objective is to use simulation program OSPSM to evaluate the performance of on street parking. The first stage of this research project takes the basic measurements carried out using video camera. The basic measurements are traffic flow, operating speed, parking time, unparking time, gap, and average duration. The second stage of the simulation program OSPSM was to run it using all the observed input parameters to obtain some measures of effectiveness such as the delays caused to through vehicles, the delays caused to parked vehicles, reduction in capacity, turnover rate, Parking Index, Parking accumulation. The main conclusion to the performance of on street parking is that it is reasonable, the average delay of parked vehicles and through vehicles at AL-Jmahory street is accepted value.
Solar energy is the most suitable among all renewable energy options for competing with fossil fuels in desalination due to its ability to utilize both heat and power for the process. In this study, the Parabolic Trough Solar Collector (PTSC) for powering a Single Stage Flash (SSF) desalination unit was proposed for Basrah city climate, Iraq. The desalination system comprises two directly coupled sub-systems: the PTSC and the SSF desalination unit. The preheated feed brine water coming from condenser was used as a Heat Transfer Fluid (HTF) for PTSC, which gets heated to a desired temperature referred to as the Top Brine Temperature (TBT). The numerical simulations were performed via EBSILON professional 16.02 (2022) software. The effects of TBT, mass flowrate of feed brine water to get the desired TBT, solar collector area, and vacuum pressure inside flash chamber on the performance of the desalination system was studied. A major finding of the current study can be summarized as follows: The collector efficiency is enhanced eventually as TBT increases. The maximum values of distillate water in June are around 5.5, 4.56, 3.69, 2.75 and 1.85 kg/h for 12.408, 10.434, 8.3472, 6.26, and 4.1736 m² collector area respectively, when TBT 107 °C and vacuum pressure 40 kPa. For 1.598 m² collector area, the total distillate in the 1st of June amounted to 7.9 kg, with an average production rate of around 0.7 kg/h. The solar SSF system's productivity per solar collector unit area at 20 kPa, 15 kPa, and 10 kPa vacuum pressures was 4.7 kg/day/m², 5.3 kg/day/m², and 6.25 kg/day/m², respectively. The average Performance Ratio (PR) values are determined to be 0.694, 0.577, and 0.491 for 10 kPa, 15 kPa, and 20 kPa, respectively. These results are very acceptable when compared with an existing literature.
The thermoelectric behavior of different materials under various conditions has been investigated numerically by using the heat transfer module of the COMSOL Multiphysics software platform. A simulation study of the thermoelectric materials (TEM) performance was created by altering the current applied from 0.1 to 1.0 A and setting the hot side temperature (T H ) as 273 K. The impact of different performance metrics, such as cold side temperature and output voltage, has been proven and investigated. It has been shown that the material of the thermoelectric legs', length of leg, and thickness of electrodes significantly impact the thermal and electrical performance of the thermoelectric (TE) module. Appropriate ranges have been studied in the simulation, such as the amperage values applied to the unit as mentioned above, the length of the leg within a range of 1 to 8 mm, and the thickness of the electrode with different values of 0.1 to 0.5 mm, which will achieve excellent performance for the Thermoelectric unit. Modeling and simulation results demonstrated and revealed the optimal and potential use of bismuth telluride (Bi 2 Te 3 ) as well as lead telluride (PbTe) as suitable for Peltier cooling applications. As for the use of cobalt triantimonide (CoSb 3 ), it is in contrast to the two previous metals, as it is effective and appropriate if applied to power generation. The results are validated with another study from the literature, and there is an excellent agreement with an error rate that does not exceed 0.164%.
The present work aims to study the performance of reverse osmosis process at Al-Dura power station. The selected membrane which is used in this work is made from polyamide (thin film composite membrane (TFC)) constructed as spiral wound module. The basic advantages of this type of membrane are the higher productivity compared with the total volume of the module, and stability of the polymer towards the chernical effect. It was found that recovery percentage (or product rate), rejection percentage (or solute concentration in product), and concentration factor decreases with increasing operating time for reverse osmosis unit, whereas, the operating pressure for reverse osmosis unit increase with time. Maximum salt rejection percentage and Maximum recovery percentage were determined to be 96% and 75% respectively for polyamide membrane.
This paper describes a study of traffic behavior at AL-Jumhoryia street in Baghdad city. The objective is to use simulation program OSPSM to evaluate the performance of on street parking. The first stage of this research project takes the basic measurements carried out using video camera. The basic measurements are traffic flow, operating speed, parking time, unparking time, gap, and average duration. The second stage of the simulation program OSPSM was to run it using all the observed input parameters to obtain some measures of effectiveness such as the delays caused to through vehicles, the delays caused to parked vehicles, reduction in capacity, turnover rate, Parking Index, Parking accumulation. The main conclusion to the performance of on street parking is that it is reasonable, the average delay of parked vehicles and through vehicles at AL-Jmahory street is accepted value.
The present study aims to investigate the influence of heat treatment and surface finish on the behavior of crevice corrosion resistance of AISI 410 and 416 martensitic stainless steels thus, to quantify the conditions at which crevice corrosion minimize as possible. The experimental work carried out during this study involves material selection, chemical composition tests, specimens preparation before heat treatments, austenitizing at temperature range (925-1010˚C) and for holding time periods of (30, 45 and 90 min), air and oil quenching followed by tempering at heating range of (205- 605 ̊C) and for 45 min, micro hardness tests, specimens grinding, surface roughness measurements, crevice corrosion tests, crevice evaluation and microstructure tests. Theoretically, empirical equations for crevice maximum depth under the effect of surface roughness and hardness for both AISI 410 and 416 steels were determined. While for microstructure analysis, carbides average area was determined by using the ImageJ analysis program and a mathematical model was also predicted. Results showed that, as hardness and surface roughness increase crevice corrosion resistance decreases. Therefore, material treated by annealing can minimize crevice corrosion rates more than that treated with hardening.
This paper describes a study of traffic behavior at AL-Jumhoryia street in Baghdad city. The objective is to use simulation program OSPSM to evaluate the performance of on street parking. The first stage of this research project takes the basic measurements carried out using video camera. The basic measurements are traffic flow, operating speed, parking time, unparking time, gap, and average duration. The second stage of the simulation program OSPSM was to run it using all the observed input parameters to obtain some measures of effectiveness such as the delays caused to through vehicles, the delays caused to parked vehicles, reduction in capacity, turnover rate, Parking Index, Parking accumulation. The main conclusion to the performance of on street parking is that it is reasonable, the average delay of parked vehicles and through vehicles at AL-Jmahory street is accepted value.
A wind tunnel is a piece of equipment specifically designed for studying the influence of air passing over solid matters in aerodynamic research. Computational Fluid Dynamics (CFD) was used to conduct methodical research into the design and modeling of flow characteristic in a closed-loop wind tunnel. The necessary intake fan velocity was established using an analytical velocity model, and the test section's inlet conditions were produced by applying the Reynolds number equation, assuming that the Reynolds number was 500,000. Instead than using the traditional method, a full-scale CFD model of the complete wind tunnel was taken into consideration. This made it possible to improve the flow quality over the entire circuit as well as only in the test area. The test section flow quality was more impacted by upstream flow circumstances than downstream conditions, according to analysis of the guide vane designs. Therefore, careful consideration has to be done while constructing the vanes at upstream curves, especially corners that are parallel to the test section. The simulation results showed that, in the case of a fully configured wind tunnel, flow uniformity in the test section is successfully attained.
The objective of this research is to characterize new technique of copper filler addition to the brazing joints of 316L stainless steel to overcome the wetting problem between them. This technique includes the electrochemical deposition of copper on the stainless steel joint parts to insure optimum coinciding, minimum oxidation during brazing heating, and consequently good wetting and bonding. An evaluation of the present technique and a comparison with traditional one were performed. The samples ware tested to find the shear strength, microhardness, microstructure and x-ray diffractometry. In general, the present new electrodeposited fillers were clearly better than the traditional filler in producing perfect joints with higher shear strength. On the other hand, there was an opportunity of production acceptable joints with electrodeposited fillers under air environment.
This paper describes a study of traffic behavior at AL-Jumhoryia street in Baghdad city. The objective is to use simulation program OSPSM to evaluate the performance of on street parking. The first stage of this research project takes the basic measurements carried out using video camera. The basic measurements are traffic flow, operating speed, parking time, unparking time, gap, and average duration. The second stage of the simulation program OSPSM was to run it using all the observed input parameters to obtain some measures of effectiveness such as the delays caused to through vehicles, the delays caused to parked vehicles, reduction in capacity, turnover rate, Parking Index, Parking accumulation. The main conclusion to the performance of on street parking is that it is reasonable, the average delay of parked vehicles and through vehicles at AL-Jmahory street is accepted value.