Basrah Journal for Engineering Sciences

Submarine pipelines are essentially used for the transmission of gas and oil across oceans between countries or for transport between shore and offshore installations. The pipeline applications were studied to be installed in deep water, which exposed to different loads such as currents and waves in various directions, barge movements, seafloor interaction, etc. This paper developed a dynamic analysis of the J-lay suspended submarine pipeline during laying taking into account the effect of water depth, the direction of the wave heading, and sea state without vessel movement. The finite element program ANSYS R17.2 is used for modeling and analysis of the pipelines. The random sea state is modeled using the JONSWAP spectrum. It was found that the effect of the direction of wave heading on the bending moment from dynamic analysis of pipeline is obvious in a depth of (2 m) below water surface, and then gradually decreases until it disappears in depth of (100 m). Whereas the effect of wave height is obvious in a depth of (2 m) and then gradually decreases until it disappears in depth of (120 m).

Constructed wetland is engineering systems used for wastewater treatment, whose objective is to reuse water, under the controlled condition, the mechanisms of treatment that occur in natural environments, through the development and get better the process that includes the porous media, plants, and gathering microbial. This paper explains horizontal flow in constructed wetland treatment, the horizontal flow is moving through the gravel media bed and vegetation which permits the wastewater flow through roots and has contact with the biofilm created in the subsurface wetland.
To estimate the quality of treated water, some physical, chemical and biological parameters were measured.
Treated wastewater from fieldwork showed removal efficiency was increased with time and showed the average removal after detention time of 3, 4, and 6 days, respectively, (47.7 %, 53.2 %, 77.5%) removal of COD, (45.1%, 52.8%, 64.4%) removal of TN, (55.4%, 58.8%, 72.2%) removal of NH4, also average removal of Nitrate was (19.41%) after 3 days. The results showed that the system was effective in removing target pollutants.

One of the major causes of serious damage to the bridge is scoured around bridge foundations. In this study, the effect of main parameters (pier shapes, foundations shapes, level of foundation, flow intensity, and Froude number) on local scour with different shapes of non-uniform piers were experimentally investigated. The runs that occurred for three foundation shapes include (rectangular, oblong, and hexagonal), the depth of foundation in this study was 8 cm. The shapes of piers used in this study were (rectangular, oblong, and hexagonal). The results display that the depth of scour depends on the foundation level, shape of pier and foundation. The best foundation shape which gives minimum scour, was hexagonal, oblong, and rectangular shape, respectively. The results also display that positioning of foundation below bed level, leads to less values of scour depth around bridge pier. Also, the best shape of the pier that leads to minimum scour is hexagonal pier because it has minimum exposed area.

The Continuously Variable Transmission (CVT) is the blends of the efficiency of a manual transmission with the ease of using the automatic transmission. Furthermore, the CVT is a developed technology that has infinite gear ratios with a high fuel economy and high capabilities of acceleration. In this paper, a comparative study was performed of the CVT performance with the manual and automatic transmission for evaluation the fuel consumption and exhaust emissions in the parallel hybrid electric vehicle (HEV). In addition, the parallel HEV with the CVT gearbox is selected from the Advisor software and their simulation methods, and then replaced with manual and automatic transmission. Moreover, the pollutants of the catalytic converter were recorded with all the molecules reactions of the exhaust emissions. The performance evaluation of the CVT was conducted by using the different worldwide standard driving cycles to simulate driving conditions and evaluation the fuel consumption and exhaust emissions. The CVT gearbox produced the best performance results in fuel economy with a marked reduction in exhaust emissions compared with some of the results obtained from the manual and automatic transmission due to the high efficiency of controlling speed ratio, in addition to the great effect in the performance than other transmissions. Finally, the CVT gearbox is considered as a favorite in travel inside the cities for the hybrid vehicle, due to a little fuel consumption and high efficiency of controlling variant speed ratio.

In the present research, experimental and theoretical work is carried out using ecofriendly refrigeration as working fluid in the absorption system. The working pair is considered in the analysis, namely, acetone and zinc bromide. The system is designed to work under outdoor conditions in Hila city-Iraq. In the test, the outdoor conditions are varied and the hot water is used as heat source. To check the performance of the system, various operating conditions are included in this study. These varied conditions include heat source, absorber, condenser, and evaporator temperatures. The system is tested during September 2019. The results show that the COP of the absorption cooling system ranged from 0.13 to 0.487, while the temperature drop in evaporator is 16 °C. Condensation and absorption temperatures are under 41 °C, while the maximum temperature of the driving water is 80 °C. The steady-state model is analyzed by using EES program. Energy and mass balance achieved on absorption system to predict some parameters such as temperature, pressure and (COP) to compare it with the measured parameters. The results of the model satisfied the experimental results for temperatures as well as the coefficient of performance. The results also show that the generator temperature had a great effect on the system performance.

This paper aims to design and construct of an automated device for testing the scratch resistance of the polymeric materials by measuring the force required to cause a scratch on the surface of polymeric materials as well as calculating the friction coefficient from the input and output of the device. The device was made of materials available in the local market and some parts were manufactured in local mechanical workshops. The device consists of four main parts were mechanical parts, scratching mechanism parts, electrical and electronic parts and the device operating program. The device designed in this work has the following specifications: normal load (0.1 N - 325 N), sliding speed (1 mm/s - 35 mm/s), tangential force measured by the load cell (0.1 N to 294 N), the samples dimensions (length: 10 - 195 mm, width: 10 - 125 mm, and thickness: 0.25 - 50 mm), maximum scratch length of 195 mm, and the height of the indenter from the platform surface (0.25 mm to 50 mm). Scratch test and calculation of the friction coefficient were performed for samples of pure and reinforced PMMA by Silicon Oxide nanoparticles (SiO2). The results showed an increase in scratch resistance and a decrease in the friction coefficient with increasing the weight ratio of SiO2. Also, the ability of the designed device to measure the tangential force required for scratching accurately and quickly and in simple steps.

In the present study, a three dimensional simulations of the single phase laminar flow and forced convection heat transfer of water in the five layers of microchannel heat sink with both arrangement radial and a parallel divergence channel have been studied numerically. The thermal characteristics and pressure drop of the heat sink were investigated for same mass flow rate (3∙925 × 10-4 kg/s) and constant heat flux (90 W/cm2). The results obtained show that, using of the radial microchannel led to improve both the hydrodynamic and thermal performance of heat sink. It led to reduce the pressure drop by 32.5 % and increase the performance index about 1.5 compared with the parallel divergence microchannel heat sink also it gives better temperature uniformity.