Tikrit Journal of Engineering Sciences

The current research aims to evaluate the efficiency of tube settlers in removing low turbidity of Tigris River water in Mosul city, then comparing the results with the conventional settler. Laboratory model for tube settler is designed and manufactured for conducting the experiments. The model consists of a coagulation and flocculation basin containing a mixer. This basin is connected with water fixing level basin which is used to obtain a uniform flow in the model. This basin is followed by another one which is called pre-tube settler basin. After that came the tube settler unit. It consists from 4 tubes of square section and 4 x 4 cm2 in dimension and manufactured at five levels of inclination angle: 30, 40, 50, 60 and 70 degrees. These tubes are manufactured at 40 cm in length and their length can be increased by connecting additional pieces with a length of 20 cm to obtain the studied length levels: 60, 80, 100 and 120 cm. Alum is added as a coagulant with six levels at 0, 5, 10, 15, 20 and 25mg/L. At the same time, another model was designed and manufactured for conventional settler from glass for making experiments parallel to the tube settler and compare the results between them. The initial turbidity of raw water ranged from 20-29 NTU during the study period. Turbidity removal percent was used as an indicator of tube settler efficiency. The highest turbidity removal percent reached 80.53% with an effluent turbidity of 5.1 NTU at 120 cm length,15 mg/L alum dose and 60° inclination angle. The results showed an increase in turbidity removal percent with increasing the tube length at all levels of the inclination angle and alum dose. The tube settler exceeds the conventional one by 20-30% in removing percent of low turbidity within the range of 20-29 NTU of the Tigris River water. Additionally, the short detention time of tube settlers compared with the conventional one can be utilized to increase the production of the plant. This can be achieved by installing modular tube settler units in the sedimentation tanks of the old water treatment plants.

In this research we tried to improve the thermal insulation efficiency of polystyrene foam by adding some natural materials. The gebrile soil was selected for several reasons, including abundance and ease of processing before the addition - There are many previous researches for soil treatment -. We have found at ratio 20%(The proportion of the soil in the compound) the coefficient of conduction is low and then rises after this percentage As for the absorption of water it increases by increasing the soil, but at this ratio the absorption is within the permissible limit according to the specifications required for the insulation materials and also compressive strength increase with the increasing of the soil ratio because of increasing of mechanical links between the polycarbonate and polystyrene particles and composite-material’s density increasing in general.

The Iraqi climate is characterized by high temperatures in summer that require a large capacity of air conditioning systems to meet the suitable climate conditions which they are appropriate for the comfortable conditions for human especially housing units. The demerits of these systems are the high-maintenance-cost as well as high electrical power consumption, whereas the last considers currently one of the major obstacles in Iraq. This research studies the influence of two significant factors to reduce the thermal loads of the building which leads to decrease the consumption of the energy. The Study of the effect for the building's direction to the falling angle of the sunlight during the daylight in addition to the probability of reducing the thermal loadof the building, and studying the effect of shading the buildings' roofs with red tile to prevent the falling sunlight on the roofs using the design method cooling load temperature difference (Cooling Load Temperature Difference –CLTD-) to calculate the thermal loads of a building designed according to the modern Iraqi design Located in Baghdad. The results explained a decrease in the thermal load through external walls by (12.32%) when directing the building to the direction West (W) compared to the South-West (SW) trend, while the thermal load through the glass decreased by 24.9% when directing the building to the North (N )direction with a trend of South-West (SW) as well as a decrease of 8.5% for the total thermal load of the building when directing thebuilding to the direction North (N) compared to other trends and when shading the roof with a material preventing the sun reduces the rate of thermal load of the roof by 55% compared to the exposed roof. The study also shows in terms of the costs per building provides about (108787 ID / Day) of the supported governmental costs whereas the non-governmentalcost is about (55987 ID / Day)

The present study was conducted for eight wells that are distributed in A’alam sub-district in Salah al-Din province to assess the groundwater quality in this area. Water samples from these wells were taken during three months periods, one sample per month. Some physical and chemical properties of the water samples were tested by conducting on-site and laboratory tests. The water temperatures of the wells were recorded to assess its relationship with many properties of the water, including basal. The results indicated that the water of the studied wells was warm during the study period, and its temperature range was (19-24) ° C. The pH was measured and also its values were in the range (7.44-8.4). The values of total dissolved solids exceeded the permissible limits, with a minimum value of (1930) mg/L which is higher than the permissible limit in the drinking water relating to the Iraqi standard and the specifications of the World Health Organization (WHO) and the American Environmental Protection Agency (USEPA), (1000) mg/L. This increase led to a significant increase in the electrical conductivity values, which reached its lowest recorded value of (3940) microsmins/cm, which is above the permissible limit (1500) microsmins/cm. The concentration of chloride ion, which is in the range (482.7-1053) mg/L and sulfur ions, which recorded its lowest value (411) mg/L, and also this exceeded the permissible limits for both ions (250) mg/L according to the Iraqi standard and WHO standards. The study covered all the studied wells water, and its depth are found in the range (80-160) meters, which is very hard water, with a concentration of (180) mg/L. The results indicate that the water was permanently exposed to pollution and is far from optimal for most of the time. Geographic information systems (GIS) were used to produce spatial maps of the study area showing the distribution of the characteristics studied, thus providing a future database for the region, which could be used to diagnose pollution wherever it would be found.

An experimental and numerical study of tube curved flaring process was conducted to investigate the effect of strain hardening characteristic of material on the process using two metals that differ in strain hardening characteristic which are pure copper and brass (70-30) by using curved dies which have curvature ratio () of (6) and (12) and base radius of die (rd=24mm) and () is the radius of curvature. The experimental part was included experiments on specimens with an outer diameter of (39 mm) and a wall thickness of (2 mm). The expansion process was carried out for different expansion ratios that it was reached to about (32%). The results were showed that the strain hardening exponent of pure Copper more than Brass (70-30) and its value reached (0.54) for pure Copper and (0.49) for Brass (70-30). However, this paper concluded a study of the effect of strain hardening characteristics on the curved flaring process. It was found that the increasing of flaring ratio and relative axial displacement of the die through the specimen are caused increase in the relative forming stress, and its value is significant in expanded tubes with high strain hardening characteristic and it is about (0.77) in Brass and (1.42) in Copper. It also found that a little difference in the deformation of specimens' geometry which means that the deformation is not affected by the strain hardening characteristic and there is no significant difference in strain distribution. The study also included a numerical simulation using the finite element ANSYS program. The results obtained are compared with experimental data and showed good agreement.

Flood wave simulation due to hypothetical momentary failure of Mosul Dam was carried out by applying the (IBER) hydrodynamic model for the dam storage scenarios (300, 310, 320, 330 and 335) meter above sea level after testing the validity and calibration the model to identify areas that will be inundated between dam site and south Mosul City. Flood waves simulation maps representing borders, water levels and depths were drawn. The inundated areas for between dam site and north Mosul city were determined for the mentioned storage scenarios are (69.14, 114.76, 158.2, 202.5 and 245.6) km2 respectively.


The minimum and maximum percentage of the inundated area within Mosul City was also calculated to be (25.6-54.6) % respectively out of the total city area. The maximum flood wave discharges at the failed dam breach and at Mosul City due to the worst dam storage scenario (335) m a.s.l are (781132 and 337138) m3/s respectively. While the elapsed travel time for maximum discharge reaching Mosul City is (4.18) hours from the initiation of dam failure. The maximum flood depth within Mosul City is (36.7) m occurred after (4.68) hours.


Finally, the routing percentage occurred in the maximum flooding discharge (attenuation) between dam site and Mosul City for storage scenario (335) meters is 56.8% while the lag time was (4.03) hours.

The aim of this work is to study the effect of the time of shot peening 3mm diameter steel balls on the mechanical properties of (2024 - T3) aluminum alloy butt welds. The welds were joined using Friction stir welding method. Mechanical tests) Tensile strength, hardness, fatigue strength (were performed on welded joints to determine the variation of these properties. The experimental results of SP time, 5 and 10 minutes give an improvement in mechanical properties. It was found that the longer the time of shot peening the mechanical properties are increased to a certain extent than the effect begins whereas when shot peening time at 15 min the mechanical properties decrease due to the concentration of stresses and surface annealing. Results show that the best mechanical properties of the welded zone were obtained at 10 minutes shot time due to the high compressive stresses generated by shot peening.

The basic aim of the power system stabilizer is to damp the fluctuations that occur on the rotating axis of the synchronous generator that result from noise or disturbance on the power system. This is achieved by producing an appropriate damping torque for these fluctuations across the excitation circuit of the generator and for a wide range of operation conditions. The study describes the types of power system stabilizers and giving an mathematical model of the power system that consists of a synchronous machine connected to the infinite bus though transmission lines. This has been achieved by simulating the electric and mechanical equations of power systems and proposing a methodological approach to design a Fuzzy Logic Power System Stabilize (FPSS) relaying in the design on the (Matlab/Fuzzy logic toolbox).Speed deviation (Δω) and acceleration (∆ ) of the synchronous machine are chosen as the input signals to the fuzzy controller in order to achieve a good dynamic performance .The complete range for the variation of each of the two controller inputs is represented by a 7×7 decision table, i.e. 49 rules using proportional derivative like fuzzy logic. The power system (SMIB) was tested with the presence and absence of the excitation system, then (CPSS) was added, and then (FPSS).The simulation results of the proposed fuzzy logic on )SMIB( gave a better dynamic response, decreased the settling time and good performance of the stabilizer in damping the fluctuations that arise in the speed of rotation of the generator and its active power in various operating conditions when proposed (FPSS) is compared with conventional PSS. The simulation results proved the superior performance of the proposed (FPSS).

Efficient design of trickle irrigation system depends on the shape and volume of wetted soil, which are affected by many factors. Among these factors are water application rate, soil profile type, initial soil moisture, and continuous or intermittent water application. The aim of this research is to study the effect of intermittent water application on the wetting pattern and soil moisture distribution for homogeneous and layered soils under trickle source. Thirty experiments were conducted to monitor the advance of the wetting front in the soil profiles. Measurements of soil moisture content were also made at selected locations to evaluate the moisture distribution in soil. A rectangular box with inside dimensions of 147 cm*90 cm*5 cm was used to build the soil profile. One of the faces of the box is transparent. Two different soils were used; a sandy loam and a silty clay loam. The soils were air dried, sieved, and packed inside the box in accordance with their apparent densities which have been measured in the field. Four types of soil profiles were built; the first was sandy loam soil, the second was silty clay loam soil, the third was (silty clay loam/ sandy loam) layered soil, and the fourth was (sandy loam/ silty clay loam) layered soil. Three water application rates were used for each soil profile. Three continuous or intermittent applications were used; continuous applications, equally intermittent applications (120 minutes ON with 120 minutes OFF), and different intermittent applications ([1]20 minutes ON with 240 minutes OFF). In addition, several cylindrical infiltration tests were conducted to describe some characteristics of each soil. Empirical relations to predict each of vertical (under trickle source) and horizontal (at soil surface) wetting front advance were found in this study. Empirical relations to predict the percentage of applied water volume in horizontal strips as a function of soil depth and in vertical strips as a function of horizontal distance from the trickle emitter were also found. The study showed that the wetted soil volume increases as either the water application rate increases, or the intermittent application ratio increases. Also, it showed that the ratio of horizontal advance to vertical advance of wetting front increases as either the water application rate increases, or the intermittent application ratio decreases. The study demonstrated that the accumulated ratio of water application volume at a certain soil depth from trickle source increases as the intermittent application ratio decreases. Also, it demonstrated that the accumulated ratio of water application volume at a certain horizontal distance from trickle source decreases as the intermittent application ratio decreases.

Average daily data of solar radiation, relative humidity, wind speed and air temperature from 1980 to 2008 are used to estimate the daily reference evapotranspiration in the Mosul City, North of Iraq. ETo calculator software with the Penman Monteith method standardized by the Food and Agriculture Organization is used for calculations. Further, a nonlinear regression approach using SPSS Statistics is utilized to drive the daily reference evapotranspiration relationships in which ETo is function to one or more of the average daily air temperature, actual daily sunshine duration, measured wind speed at 2m height and relative humidity.

The most important problems in the Iraqi Road network that’s associated with repetitions of excessive axel traffic loading. This problem will be increased with availability of moisture, its guide to moisture damage or stripping in hot mix asphalt. In this study, it is used the low-density polyethylene polymer (LDPE). It's cheap, and available as local material (particles) in Baghdad Plastic Factories or bags of soft plastic waste, therefore; it's based by searching about the active range of developing asphalt upon moisture damage, and searching about admixture optimum polymer ratio to be added to asphalt to increase stripping resistance. The local materials were used as AL-Daurah Refinery asphalt that have penetration (40-50) or, (PG64-16) and nominal aggregate (19) mm from AL-Nibaie Quarry that’s used in binder asphalt pavement. Prepared five percentage of polymer (1%,2%,3%,4%,5%) was added to optimum designed asphalt of (4.8%) by weight and then results were compared with original asphalt and studying the mechanical, and physical properties of asphalt mix. The better polymer percentage found as (3%) for developing the specification of resistance stripping and this characteristic developed to ratio (33.1%) at temperature (25 ), and (26.7%) at (60 ).

This research depends on carrying out an applied and numerical analysis for capability to utilize winds turbines which considered as means of renewable and friendly energy to environment, and how to make use of this technology to generate electric energy in Kirkuk city. Where it was studied shifting kinetic energy of winds into mechanic energy and has been accomplishes install a horizontal-turbine in one of work sites in Kirkuk city of (16m) height of the ground level. It has tri-blades of (400W) power. It has been connected to an electric system supply designed and manufacture during the research period. In order to measure the voltage-difference and electric current consequently to measure the power and energy produced from the wind turbine and changed according to the wind speed alteration. Gauge records for two time seasons are taken by using the technology-programming of delicate controller in simultaneous work with meteorological system, so that it can set data-principle to be analyzed by using (MATLAB) program to find and check theoretical generated power compared with practical results and find the range of validity to generate the sufficient energy for domestic consumption. The results shows that summer season is better than winter season in using wind turbine in Kirkuk city. As the monthly energy rate produce during summer season has emerged to ten-time than monthly energy rate produced during winter season.