Browsing by Author "Marzouki, Riadh"

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Citation Count: Fan, Guangli...et al. (2021). "Energy and exergy and economic (3E) analysis of a two-stage organic Rankine cycle for single flash geothermal power plant exhaust exergy recovery", Case Studies in Thermal Engineering, Vol. 28.
Energy and exergy and economic (3E) analysis of a two-stage organic Rankine cycle for single flash geothermal power plant exhaust exergy recovery
(2021) Fan, Guangli; Gao, Yingjie; Ayed, Hamdi; Marzouki, Riadh; Aryanfar, Yashar; Jarad, Fahd; Guo, Peixi; 234808
A two-stage ORC (Organic Rankine Cycle) is being proposed for the recovery and utilization of low-grade heat from single flash geothermal power plant exhaust flue fluids. The working fluids for two-stage the recovery system are R227ea and R116. The impact of essential design parameters such as inlet temperature of the cycle, ambient temperature, geothermal turbine inlet pressure, geothermal condensation temperature on system performance are investigated using thermodynamic mathematical models regarding energy and exergy efficiencies as the objective function. The addition of the recovery section to the base cycle improves the thermal efficiency from 0.2023 to 0.2178, a 7.66% improvement in this critical metric. Furthermore, the exergy efficiency rises from 0.55044 to 0.5803, representing a 15.04% boost in exergy efficiency. Furthermore, the system's overall output rises from 7690 kW to 9898 kW, representing a substantial gain of 28.71%. The suggested recovery system's cycle has a lower LEC than a single flash geothermal cycle from an economic standpoint. LEC Reduced from $ 0.125 per kilowatt to $ 0.108 per kw, a cost savings. As a result, including a recovery section in the basic single flash geothermal cycle will significantly improve system performance.
Citation Count: Chen, Heng...et al. (2021). "Thermal, hydraulic, exergitic and economic evaluation of a flat tube heat exchanger equipped with a plain and modified conical turbulator", Case Studies in Thermal Engineering, Vol. 28.
Thermal, hydraulic, exergitic and economic evaluation of a flat tube heat exchanger equipped with a plain and modified conical turbulator
(2021) Chen, Heng; Ayed, Hamdi; Marzouki, Riadh; Emami, Faezeh; Mahariq, Ibrahim; Jarad, Fahd; 234808
Increasing use of fossil fuels has led to serious consequences on the environment including global warming, pollution, and increased costs of heating systems. This indicates the importance of improving the efficiency of devices used in heating and air conditioning systems such as heat exchangers. In this study, it was tried to enhance the performance of the heat exchanger by simultaneous use of a flat tube as a central tube of the heat exchanger and dual conic turbulator. In addition to plain conical turbulator, the influence of the conical turbulator with aerodynamic geometry was investigated on the heat transfer and pressure drop. Finally, economic evaluation of the studied cases was done based on the thermal performance enhancement factor (TEF) and the net profit of unit transferred heat load (ηp). Tests were conducted in the hot water flow rate ranging 0.033–0.0678 L/s while cold water flow rate was kept constant at 0.166 L/s. The results indicated that the heat transfers and exergy loss of the flat tube heat exchanger with a dual modified conical turbulator was up to 33% and 30% higher than the plain tube heat exchanger, respectively. Also, a heat exchanger with a modified dual turbulator with convergent embellishment (case B) selected as the economic case and has the highest TEF and ηp. It was revealed that the application of enhanced conical turbulator would lead in the increment of ηp up to 1.26 times.