KUFA JOURNAL OF ENGINEERING

Over the past years, the high generation of municipal solid waste has been identified as a considerable global environmental issue, due to population growth, economic development, and the industrial revolution. The present research study was conducted to evaluate the quantity, ingredients, and generation of municipal solid waste (MSW) in Pshdar district during winter and summer in 2019. The results revealed that the average of solid waste production in the district reached 94 tons/day and 0.761kg-capita/day. The most abundant MSW constituents are organic matter forming 75.71% of MSW of the district, followed by 13.18% of plastic content and the least ingredient is metal 0.93%. While the average ratio of paper and cardboard, textile and leather, and glass waste ingredients are 3.74%, 4.85%, and 1.66% respectively. The seasonal effect on solid waste content has been observed obviously in this research, more specifically in organic matter and textile & leather, as well as in waste generation rate. Organic matter increased from 70.73% to 80.68% from winter to summer, while, percentage of textile and leather significantly declined from 6.93% to 2.76% from winter to summer. Similarly, waste generation rate was reduced from wet to dry season from 0.846kg-cap/day to 0.676kg-cap/day.

A two-dimensional numerical investigation on laminar forced convection is carried out to estimate the thermal and fluid field behavior of Al2O3-water nanofluid in a circular pipe with constant heat flux. In this study, the finite element method (FEM) is employed to analyze the continuity, momentum, and energy governing equations by using COMSOL Multiphysics 3.5a. Computations of heat transfer rates were performed for a range of Reynolds numbers (Re ≤ 2000), and (Pr= 5.42). The effects of Reynolds number and fraction volume of nanoparticle (ɸ≤ 5%) on the mean coefficient of convection (havg), pressure drop (∆P), and thermal-hydraulic performance are investigated. The computations indicate that Al2O3 nanoparticle usage augments the average coefficient of heat convection significantly, and which is increased by (10%) with maximum pressure loss (15%) for (ɸ=5%) and high Reynolds number when compared to the base fluid. The present model is validated with empirical Shah Equation and the results showed a good agreement.

Gutters are used to drain water way off to the Inlet. This process significantly reduces the phenomenon of hydroplaning and thus reduces traffic accidents. The main objective of this study is to evaluate the effect of the characteristics road (manning's coefficient, longitudinal slope, and cross slope) on the capacity of gutter, and spread as well as the change which was clarified for all gutters types. Two simulation models have been developed in this study, which represent the major components of the system. These models are spread Model (SM), Gutter Capacity Model (GCM), and the first model studies spread if rain information is available, while the second model studies a gutter capacity if no rain information is available. The study reached at the conclusion: gutter capacity is inverse proportion with manning’s coefficient and directly proportional with cross slope and longitudinal slope for road. Affect spread is different according to form gutter.

Middle East has suffered from drought since many decades because of climate changes; therefore, surface water has become scarce in many countries such as Iraq. It seems, in general that groundwater is the alternative best solution to cover the lack in water requirements of domestic, agriculture, and industry. In this study, environmental assessment was carried out for 29 wells in Najaf Governorate to evaluate their water suitability for irrigation use. This bases on comparison between 8 water quality parameters with their limitations at Food and Agriculture Organization guideline (FAO) beside British Colombia guideline (BC), the parameters are: nickel, chromium, lead, zinc, cadmium, sulfates, hydrogen power (pH), and total dissolved solids. The study outcome clarifies that there are only 4 wells have suitable water for irrigation use, the others have at least one parameter not applicable with the international guidelines of FAO and BC, which are probably not appropriate for irrigation.

Attic design has a significant impact on buildings’ energy performance thus making investigation of its thermal performance characteristics imperative. Raised-ceiling is among the common complex attic configuration found in pitched-roof buildings. In this study, natural convection inside a raised-ceiling rooftop heated isothermally from the base wall (ceiling) is numerically investigated at a certain pitch angle range while keeping the enclosure base-length unchanged. The results show that the roof pitch and the kinks on the ceiling have a strong influence on the heat and fluid flow patterns. At low roof pitch, high heat transfer rate between the cold and hot walls leads to a multi-cellular flow structure. The number, size and strength of the counter-rotating cells change with the pitch angle. The kinks caused air velocity to double for every 15° increase in the roof pitch. The rate of convective heat transfer is enhanced with decreasing value of the aspect ratio.

In this paper, the elasto-hydrodynamic (EHD) performance of partial journal bearings has been studied. A numerical analysis has been conducted using the ANSYS Workbench (17.2) platform to investigate the performance of partial journal bearings. The lubricant used is considered Newtonian and incompressible fluid that flows steadily under laminar conditions, while the bearing material is assumed to be elastic, isotropic with smooth surface conditions. In the current FSI analysis, the lubricant flow has been predicted according to the finite_ volume method, while the finite element method has been adopted to compute the deformation and stress in the bearing surface. A wide range of operating and design conditions have been considered including the eccentricity ratio (0.1≤ε≤0.82), and arc bearing angle bearing (90ᵒ≤θ≤180ᵒ), while the values of bearing length to diameter ratio (L /D) and rotation speed (N) have been fixed at=0.77 and 1500r.p.m, respectively. The hydrodynamic pressure, performance characteristic of journal bearing, stress, and deformation have all been computed. It was found that the arc bearing angle and eccentricity ratio has a clear effect on the elasto-hydrodynamic properties of the partial bearings especially at high values of them.