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Go to Editorial Manager50W monocrystalline silicon solar module performance is tested with experimental measurements conducted at Baghdad city /Al-Jaderia (33.26 N, 44.21E). Solar irradiance striking is subjected to more losses which after the experiments conducted resulted approximately in 15% of the total energy which is converted into electric power energy. To study the effect of temperature variations on solar performance, solar irradiance must be kept constant and vice versa. Therefore, to have of the temperature range and for more accuracy, the measurements was done for tested module with three solar radiations levels; 500, 750 and 1000 W/m2. The maximum value of power (Pmax) at solar radiation intensity 1000W/m² was 46.34 W on January 2025 at cell temperature 24.1 oC, with the corresponding the maximum open voltage, and open circuit current 18.28 V, and 2.944 A respectively. The highest value of efficiency was 13.5 % January 2025 at solar radiation 500W/m². Consequently, The minimum value of power (Pmax) at solar radiation intensity 500W/m² was 27.54 W on October 2024 at cell temperature 40.5 oC, with the corresponding the maximum open voltage, and open circuit current 18.01 V, and 1.752 A respectively. The lowest value of efficiency was 6.9 % October 2024 at solar radiation 1000W/m². In general, the results showed slightly decrease in short circuit current with temperature increasing. With temperatures change great influence on the output voltage especially on open circuit voltage while very small decrease in the output current has been noticed.
ABSTRACT This paper proposes a low CAPEX selective blending strategy to upgrade regular gasoline quality in Diwaniyah Refinery. It tests the hypothesis that segregating heavy naphtha from the gasoline pool and blending light naphtha only with imported high octane gasoline can increase octane number (RON) and reduce sulfur content while decreasing import requirements. Four volumetric cases were evaluated: the refinery’s current practice (72 vol% imported gasoline + 28 vol% mixed naphtha) and three alternatives replacing mixed naphtha with light naphtha at 72/28, 67/33, and 62/38 vol%. Blends were prepared at ambient conditions and characterized using ASTM D2699 (RON) and ASTM D5453 (sulfur content). Replacing mixed naphtha with light naphtha at the same import ratio increased RON from 82.5 to 84.5 and reduced sulfur content from 157 to 70 ppm. Further reductions in imported high octane gasoline to 67 and 62 vol% maintained sulfur content below 100 ppm (77 and 87 ppm), with RON values of 83.5 and 80.5, respectively. These results were confirmed by Aspen Hysys simulation and ANOVA, indicating that heavy naphtha exerts the strongest negative effect on quality of regular gasoline. The proposed segregation requires only modifications to pipeline routes, enabling improved fuel quality and compliance with sulfur standards while reducing the need for imported gasoline in smaller refineries.
In this research paper, it has been studied the influence of the temperature of the cell on the performance and behavior of two types of modules, which are mono-crystalline silicon (mc-Si) and poly-crystalline silicon (pc-Si) solar modules. The experimental work has been achieved under the outdoor conditions, where the range of cell temperature is between 20 and 60 °C. It was applied three different values of solar radiation [500, 750, and 1000W/m2 (standard condition, where cell temperature of 25 °C, solar irradiance of 1000 W/m², and air mass AM 1.5)]. All tests are achieved under the Iraqi weather conditions in the city of Baghdad city. It was computed the temperature coefficients for each module and during any time during the experiment. It was found that the open circuit voltage decreased with -0.0912 V/ºC and -0.07 V/ºC when using the pc-Si module and mc-Si, respectively. While, the short circuit current increased slightly with 4.4 mA/ºC and 0.3 mA/ºC corresponding to the pc-Si and mc-Si, respectively. Finally, the lowest drop in output power was found when using the pc-Si module (-0.0915 W/ ºC), and the highest drop when using the mc-Si module (-0.1353 W/ ºC).
The objective of the current study is to determine the accuracy of a computational model that has been developed to simulate polyurethane foaming reactions by comparing its results with experimental findings on the system using both physical and chemical blowing agents. There was high concordance between the model outputs and the laboratory results in regard to the temporal development of reaction temperature as well as the resulting foam density, both of which were highly faithful recreations. The discussion provided further information about the optimization of the performance of cyclohexane, particularly when used in synergy with chemically active blowing agents, which speed up foaming. Besides, the polymerization dynamics were contained in the simulation, thus providing rich information on the structural changes that occur during the foaming process. Taken together, the results present a strong basis for the process performance optimization, as well as the predictive modeling of the blowing agent behavior. In the future, it will involve expanding the simulation model to include a wider range of agents, reaction mechanisms, and kinetics.
Polyurethane (PU) products enjoy remarkable versatility due to their tunable chemistry, segmented structure, and a wide range of mechanical properties, making them useful in flexible foam products, structural systems, and biomedical applications. However, the complex multiphase morphology and the strong interaction between reaction and processing processes make experimental characterization incomprehensible on its own. In turn, computational studies have become essential to study and design PU systems at a range of spatial and temporal scales. The current review provides an overview of simulation methodologies that are relevant to polyurethane, including atomistic molecular dynamics (MD), coarse-grained (CG), and mesoscale simulations, including dissipative particle dynamics (DPD), finite element method (FEM) modeling, and computational fluid dynamics (CFD) simulations. Atomistic models provide data on molecular interactions, hydrogen bonding, and thermomechanical behavior, and CG and mesoscale methods on phase separation and morphological evolution. At the bigger length scale, nonlinear mechanical response can be predicted using FEM, whereas foaming and mold-filling processes can be predicted using CFD that is coupled with reaction kinetics and population balance equations. Its focus is on multiscale modeling strategies, which combine these apparently different approaches, hence allowing the explanation of structure-property-process links. New trends and modern issues, including the integration of machine learning and tool models of digital twins, are also mentioned, highlighting new opportunities in predictive design, based on simulations, of polyurethane materials.
The aim of this study is to optimize ESP performance by evaluating the current conditions and the performance optimization of the electrical submersible pump (ESP) for six oil wells in the Rmelan oil field. fluid and reservoir properties (API = 23, T = 78 C°, pressure of reservoir = 160 atm and the WC is 70%). This paper presents a sensitivity assay conducted by Nodal Analysis (Using PIPESIM Software) on the pump frequency and wellhead pressure. The outflow tubing performance and inflow performance relationship were generated and plotted for each well. The curves are investigated, indicating problems in some wells (W-12R, W-21KH, and W-21SH). The results of this study show that we can increase the flow rate by optimizing the ESP performance by decreasing the wellhead pressure to 71.58 psi and raising the frequency of ESP to a specific value of about 65 Hz based on the limites of production of each types pump capacity . Increasing the frequency from 55 to 65 Hz resulted in increasing the production from 634 to 1092 bb/day for W-12R, from 1928 to 2806 bbl/day for W-21KH, and from 1722 to 2279 bbl/day for W-21SH.
Micro-management is a type of management in which the manager accurately monitors and intervenes or regulates the work of his subordinates or his employees in detail, and it is the attempt of managers to interfere, influence and control anything in the team, situation or place, Everything in this world carries two different directions, one negative and the other positive, and we aim in this research to exploit the advantages of the method of micromanagement and prove that it can be a successful tool if used correctly and at specific times and within certain limits, in this research the factors affecting Applying this method in construction contracting companies in Iraq to take advantage of this method in identifying the most important problems leading to financial corruption in order to eliminate or reduce them in order to advance the current reality of projects, so the researcher reached the most important factors, including (administrative style, organizational culture) and other factors that have been clarified in a way. In detail in this research, the characteristics of the micromanager were also studied, which represent the cornerstone of the success and failure of this technique, as the effect of each characteristic and the possibility of its availability in the vicinity of engineering companies was addressed.