http://dspace-su.server.ly:8080/xmlui/handle/123456789/2282 2026-05-01T12:45:38Z http://dspace-su.server.ly:8080/xmlui/handle/123456789/2323 Experimental Works to Improve Power Quality of the Existing PV Solar Inverters Ali Algaddafi; Abdelrahim N. Esgiar; Eljaroshi Diryak; I.M. Saleh Solar energy development has attracted significant research attention, due to it offering many advantages that include being a safe, clean, and non-finite resource with no operational costs or moving parts. Therefore, solar systems are expected to play a significant role in the future of electricity supply, but, the power electronics used to connect these resources to the grid may face problems. This paper presents improving the power quality of the existing PV inverter by integrating it with a bidirectional inverter along with a battery storage system. A 6 kWh AC Mini-Grid is developed and tested with a PV inverter. The experimental works found that the PV inverter has high the Total Harmonic Distortion (THD) of the output current that may reach up to 24%, while when this PV inverter was connected to the proposed system, the THD of the output current of the PV inverter was reduced to 0.64 %. The response of the battery storage is very smooth and fast, providing a stable and reliable output power in both cases when a domestic load is supplied from the solar system or the battery storage. 2023-01-01T00:00:00Z http://dspace-su.server.ly:8080/xmlui/handle/123456789/2320 Design, modeling and simulation of a square quartz resonant pressure sensor Mohamed E. Ali This paper establishes the Finite Element Method FEM model of a practical Quartz beam resonator attached to a square diaphragm, which is used for measuring the pressure, based on sensing mechanism of a resonant Quartz pressure sensor. The relationship between the basic neutral frequency of the beam resonator and the measured pressure is calculated, analyzed and investigated by making use of the established FEM model. Some important qualitative and quantitative results on the natural frequency- pressure relationship of the beam resonator and the microsensor are obtained. Finally, based on the differential output scheme, a set of appropriate parameters of the sensing structure is determined, the frequency range is (661.839~892.208) kHz for the beam, which is located at the outer edge. 2023-01-01T00:00:00Z http://dspace-su.server.ly:8080/xmlui/handle/123456789/2319 Design M×N Adaptive Antenna Array for Personal - Satellite Communications Link Mabrouka H. A. Ehtaiba; Hend M. Elamari This paper introduces a proposed design of an adaptive rectangular microstrip antenna array for personal - satellite communications link operating at 3 GHz. The main purpose is to design an antenna with an adaptive narrow main beam bandwidth directing up to the satellite by using smart antenna techniques. The performance of the proposed planer antenna in terms of patch width and length, number of elements along the x-axis and y-axis, the spacing between the elements, directivity, distribution, weighting coefficients, and radiation pattern are studied and optimized using Matlab software. High directivity of 13.12 dB is achieved. Therefore, high orbits satellites cab be utilized to reduce the cost. 2023-01-01T00:00:00Z http://dspace-su.server.ly:8080/xmlui/handle/123456789/2317 Modified Empirical Models for Predicting Liquid Film Thickness in Different-Sized Vertical Pipes Almabrok A. Almabrok The liquid film thickness is a vital parameter in many engineering applications such as production equipment of oil and gas. Good control of fluid flow in such equipment can lead to maintaining a continuous liquid film on the pipe wall and hence increasing the anticipated production rate and avoiding catastrophic consequences. Therefore, a precise estimation of liquid film behavior is required to achieve the targeted production rate and overcome the above-mentioned issues. Even though a considerable number of empirical models were reported, most of these assessed the fluid flow based on small-sized pipes. These models incorrectly predicted the film thickness if applied to a large-diameter. This work was aimed at developing correlations for gas-liquid two-phase fluid in order to be applicable for different-sized pipes. The new correlations were evaluated against a wide range of experimental data of liquid film and for different diameters collected from the literature on vertical pipes. It was found that the new correlations can be precisely used for predicting the liquid film behavior in small and large pipe diameters. 2023-01-01T00:00:00Z