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Design of a Single-Phase Inverter for Solar Energy Conversion System
Get PDFSince the calculation of the active and reactive power is considered an essential topic nowadays, the novel method is focused on these calculations with omitting the PLL that will decrease the complexity of the control process. To get the maximum photovoltaic (PV) output, the maximum power point tracker (MPPT) algorithm has been integrated with the proposed method. MATLAB/SIMULINK has been used to show the performance of the proposed method. The simulation outcomes verify the advantage of the novel method by improving the total harmonic distortion (THD) and the system stability regardless of load changes
Performance of PV panel under shaded condition
Get PDF Abstract. One of the most important technical aspects to consider during the technical study and practical installation of the solar panels is choosing the location of the solar panels, Because it's probable that some of its cells will be shaded. PV characteristics become more complex under partial shade situations, with several peaks.Partial shading affects the performance of the solar cell in proportion to the state of shadow; this negative performance will be reflected on the current generated by the solar cell; of the current value of the other cells (being connected in series) which will decrease the overall performance of the solar panel. The goal of this study is to demonstrate the impacts of partial shade on a PV array by analyzing various shading situations.First, this is done using Matlab/Simulink
Seasonal Activity and Sensitivity of Some Tomato Cultivars to Tetranychus urticae Koch.
Get PDFThe results of the current study showed that the first appearance of Tetranychus urticae on the leaves of tomato plants in the field was on 7/14/2020 and that the highest average number of mites was on 17/8/2020 (371.78) individuals/10 leaves, while the lowest average for these numbers was recorded on 5 /10 (23.19 individuals), and the highest average of these numbers was on the Nabaa variety (240.05 individuals), while the lowest average of these numbers was recorded on the local variety (102.26 individuals). The correlation was positive and significant between the number of mites and the average weekly temperature (0.750) * and significant negative (0.685 * -) with the relative humidity. The lowest mean of infestation was on the tomato cultivars Sandra (69.97%) and GS (63.05%). Based on the criteria of % of infested leaves and mite population density, the tomato cultivars GS and local were the least sensitive to infection, respectively. The correlation values were insignificantly negative between of the affected leaves and the content of these leaves of proteins (-0.262), carbohydrates (-0.476) and flavonoids (-0.221), while it was significant positive with phenols (0.751) and insignificantly positive with alkaloids (0.432)
Performance Evaluation of Shell and Tube Heat Exchanger by Using Fe3O4/water Nanofluidid
Get PDF This paper studies the forced convection heat transfer and flow characteristics of nanofluids composed of water and different volume concentrations of Fe3O4/water nanofluids (0.35%, 0.2%) under laminar flow conditions that move in counter current in a vertical shell-and-tube heat exchanger. Fe3O4 nanoparticles having a diameter of about 30 nm were used in this work. Various of Reynolds number were used during practical experiments on the device is (200,600,1000,1400). The results show that for the same mass flow and inlet temperature, the convective heat transfer coefficient of the nanofluid is slightly larger than that of the base fluid where the improvement ratio is up to 14%, 22% for 0.2%, 0.35%, respectively. Where it was concluded through the results that the total coefficient of heat transfer of the nanofluid has increased compared to the basic fluid, the maximum improvement at (0.2%, 0.35%) was about 34% and 61%, respectively. When the concentration of nanofluids increases sharply, the Nusselt number also increases sharply compared with the base fluid up to 10%, 19%. As the results showed that the friction factor increases when the concentration of nanofluid increase because the density and viscosity is higher than of base fluid, while decrease when the Reynolds number increase, where the ratios reached 25%, 47%. It was found that the effectiveness of nanofluids is higher than that of base fluids is up to 56%, 62%
Numerical Simulation of a Ground-Supported Solar Panel PV Array Subjected to Periodic Flow
Get PDFDetailed numerical modeling and research were conducted to assess the influence of wind loads on various solar arrays using commercial software such as Ansys. A large amount of damage has been recorded from solar arrays and mounting frames worldwide owing to strong winds. This paper exemplifies the analysis of displacement and stresses of the structure due to strong wind flow and wind load around the solar panel. Since the solar panels are located in the same panel array at the same spacing, we assume that periodic flow conditions can be applied in the flow direction. The model displays a flow field with a free flow velocity of 10 m/s , 25 m/s, and 50 m/s and calculates the resulting structural stresses and displacements. This model uses two other studies. Initially, Turbulent Flow, a k? physical interface, is used to resolve turbulence around the solar panel. The other uses the Solid Structure physical interface to resolve structural stresses and displacements. Fluid Structure Interaction, Fixed Geometry Multiple physical coupling features are used to connect the boundary load of a fluid flow to a solid region in the fluid region. It corresponds to unidirectional fluid structure interaction analysis.
Study of histopathological and Histochemical changes Caused by Toxoplasma gondii in Vision Systems of Mice congenitally infected and the synergistic effect of Malarone and Clindamycin
Get PDFThe present work was conducted aiming at isolating and diagnosing Toxoplasma gondii from the placentae of infected women and inducing infection in female Swiss albino mice, through intraperitoneal injection resulted in 100% infection rate.
Evaluation of malarone and clindamycin, single and synergistic between them in infection of female mice on the tenth day of gestation and delivery and confirmation of congenital infection, treatment was started at the age of one month with the above mentioned drugs. The criteria considered were the number of dead mice, the percentage of survival, and the average number of brain tissue cysts. Treatment with the synergized malarone and clindamycin were used to treat congenitally infected mice, number of death was not reported and the survival rate was 100%. Average numbers of brain tissue cysts are reduced to 5.55 in adult infected mice and the cure rate was 100%.
Histopathological effects that occurred in the congenitally affected females, they were the appearance of hyperplasia and introversion of the retina several folds and the presence of scars that connect the retina to the choroid, and the reduction of the visual papilla, and it was noted for the first time by using the Congo red stain, signs of amyloid deposits in the vitreous fluid and in the debris of the lens that appeared irregular and seemed filled with fluid. And fatty materials and debris residues of lentil fibers. It was observed for the first time that the optic nerve was doubled using Mallory's triple stain. As for the brains, the same changes were observed, and amyloidosis appeared using the toludine stain. When using the treatment malaron and clindamycin at a dose of 100 mg/kg synergistically, the effect of infection in the eyes was slight and a noticeable improvement appeared in the brains.
As for the histochemistry of stains and their components, and brain, different response were noted between strong +ev control and –ev for those treated with the two drugs malarone and clindamycin at a dose of 200mg/kg with PAS stain and Alician blue stain pH 2.5%. For Von kossa stain and Pearl`s stain, different responses also appeared in the eyes and the brains.For Feulgen stain, used to detect apoptosis good results was obtained in eyes, brains
Effect of Nitrogen and Organic Fertilization on Growth and Yield of Two Cabbage Varieties Brassica oleracae Var. Capitata
No full textThe experiment was conducted at the vegetable field of Department of Horticulture and Landscape / College of Agriculture and Forestry / University of Mosul during the growing season 2019/2020 to study the effect of three factors: the first, two varieties of cabbage )Copenhagen market and Cherman(, the second, three levels of nitrogen fertilizer )0, 200 and 400 kg. ha-1(, and the third: two concentrations of humic acid )0 and 6 ml. L-1(, by using the split-split plots system within randomized complete blocks design RCBD with three replications. The results were as follows(please discussion the first factor and 2nd and 3rd and interaction between two and three factors: The treatment of Copenhagen market cultivar and fertilizer 400 kg N. ha-1 with humic 6 ml.L-1 were significantly superior in all studied traits represented in head circumference 58.50 cm and the number of unwound outer leaves 20.83 leaves. Plant-1, the number of inner-coiled 35.00 leaves. Plant-1, stem weight, stem length and total head weight 2918 g, and marketing head weight 1774 g, total and marketable yield of heads 121.581 and 73.901 t. ha-1, respectively, and percentage of dry matter in leaves 10.03% compared to the other treatments
The Reality of Intuitive Intelligence of leaders at the University of Salah Al-Din: a Swab Study
Get PDFThe current research aimed at standing on the reality of the intuitive intelligence of leaders at the University of Salah Al-Din, in the light of the opinions of an intentional sample represented by the deans, their assistants, and departmental councils in the researched university. After analyzing the data obtained by adopting the statistical program (SPSS). the researcher reached a number of results in the light of which the appropriate conclusions were crystallized. The most important of which is the interest of leaders at Salah Al-Din University greatly in learning and increasing knowledge and thus enhancing organizational learning and organizational memory. These conclusions led the researcher to present some proposals; the most important of which is the need for leaders at Salah Al-Din University to be ready to face challenges and not stick to decisions and routine procedures because the circumstances surrounding decisions are changing rapidly, so leaders must be more daring in dealing with matters
Neural Network Based Assessment the performance of the triangular in-tegrated collector
Get PDFA numerical study was achieved on a new design of storage solar collector by using neural network (NN). The storage collector is a triangular face and a right triangular pyramid for the volumetric shape. It is obtained by cutting a cube from one upper corner at 45o, down to the opposite hypotenuse of the base of the cube. The numerical study was carried out using the computational fluid dynamics code (ANSYS-Fluent) software with natural convection phenomenon in the pyramid enclosure. The results show that, the temperature and velocity distributions throughout the operating period were obtained. The influence of introducing an internal partition inside the triangular storage collector was investigated. Also the optimum geometry and location for this partition were obtained. The enhancement was best at y= 0.25 m whereas the height of triangular collector was 0.5 m. The hourly system performance was evaluated for all test conditions. The performance of the NN to train a model for this work was 0.000207, while the error of the calculation was 1*10^-2 as average