Seyyed Faramarz Ranjbar

The ongoing transition in the energy sector demands more efficient and reliable energy storage solutions. Our study addresses this need by optimizing the industrial process of liquefied natural gas (LNG) storage, focusing on enhancing thermal performance and energy efficiency. Leveraging a standard LNG storage design, we meticulously evaluated critical supporting variables, modeled key components, and conducted integrated cycle simulations. The primary goal was to minimize the volume of stored gas (achieving a reduction to approximately 1/600th of its gaseous state) while maintaining optimal storage conditions. Our methodology prioritizes insulation over pressure‐bearing factors in large‐scale tanks, aligning with the unique thermal challenges of LNG storage. Simulations were based on methane, which constitutes over 86% of the natural gas in the Middle East, ensuring relevance to the region's resources. The results are promising, with a compression stage reaching a maximum pressure of 2.377, an energy efficiency ratio of 60.71%, and a performance coefficient of 3.188. These findings offer a significant step forward in developing more effective and efficient LNG storage systems, contributing to the broader goal of sustainable energy management.

This study investigates the potential of using phase change material (PCM) in a building using an air handling unit (AHU) assisted by solar energy. To further enhance the system, an energy storage system (ESS) can be considered. Implementing ESS would allow the captured solar energy to be stored efficiently, ensuring a continuous and reliable power source for cooling or heating the air, even during non‐sunlight hours. The air‐conditioned zone is considered to be 220 m² in which 30 people work for 12 h a day. An energy analysis is conducted to evaluate the performance of the proposed system in terms of energy and exergy loss. The genetic algorithm (GA) method is used to optimize the system. The results indicate that the system, including PCM and solar system, can reduce energy consumption by up to 8.9% compared to conventional AHUs in the hottest month of the year (July). The results indicated that employing PCM leads to a decrease of 124 kWh in heat loss during January and 229 kWh in heat gain during July. Taking into account the beneficial impacts of both PCM and the solar system, the yearly assessment demonstrates a 2.69% reduction in power demand, equating to an energy saving of 679 kWh. Furthermore, PCM in the proposed system can be used in integration with AHUs based on renewable energy systems to store renewable energy for buildings.

Scramjet engines are considered a highly promising technology for improving high-speed flight. In this study, we investigate the effects of using multi-extruded nozzles on fuel mixing and distribution inside the combustion chamber at supersonic flow. Additionally, we explore the impact of an inner air jet on fuel mixing in annular nozzles. To model fuel penetration in the combustor, we employ a computational technique. Our study compares the roles of three different extruded injectors on fuel diffusion and distribution at supersonic cross-flow. Our findings reveal that the use of an inner air jet increases fuel mixing in the annular jet, while the use of extruded nozzles improves fuel distribution by enhancing the vortices between injectors. These results demonstrate the potential benefits of incorporating multi-extruded nozzles and inner air jets in the design of scramjet engines.

This study deals with dynamic modeling and analyzing of an innovative semi-solar greenhouse structure applying MATLAB software from the viewpoints of energy, exergy and economic. This Modeling is applied to predict the temperatures of four different points inside the semi-solar greenhouse, regarding the evapotranspiration of the crop. Measured data recorded from the constructed typical semi-solar greenhouse is used to evaluate the results of the proposed thermodynamic analysis. Measurements during the experiment show considerable temperature difference of 20 ℃ between the indoor and outdoor air. The mean values of 5.94% and 2.06℃ for MAPE(Mean Absolute Percentage Error) and RMSE(Root Mean Squared Error) indicates the accuracy of the thermal simulation. Furthermore, in different heat and mass transfer processes, the total exergy destruction values are analyzed. The target of this research is considered as providing suitable environmental conditions for the inside of the greenhouse. In this respect, the greenhouse air unit cost for each time step of one minute is inspected. By increasing the interest rate from 10% to 20% the greenhouse air unit cost raises almost twice. Decrease of about 45.36 % in total exergy destruction is obtained by the technique of applying double layer glass as the greenhouse cover.