Print ISSN: 1681-6900

Online ISSN: 2412-0758

Keywords : Cooling

Preparing Nanofluids (Al2O3) for Enhancement Performance of Photovoltaic

Mohammed Saadoon; Ibtisam A. Hasan; Mohammed J. Mohammed

Engineering and Technology Journal, 2021, Volume 39, Issue 9, Pages 1445-1453
DOI: 10.30684/etj.v39i9.2110

Photovoltaic (PV) panels produce electrical energy comparable to the cumulative amount of PV radiation generated on surface of sun. The solar modules influence on temperature of PV panel and for work with its standard specifications in Iraqi environment can be used nanofluid for cooling PV and improve performance. The developed thermal model for proposed cooling method has shown on the way to be an efficient design tool that can help engineers to reduce the time and cost of experimental testing. The improvement in temperature reduction using direct flow technique at rear sides of PV panel achieved electrical and thermal performance enhancement. The enhancement of overall efficiency at 1 g of nanofluid  is  showed  15%  but in 1.5g  nanofluid is  18%. As well as the enhancement of thermal efficiency at 1 g and1.5g of nanofluid are showed 19% and 27% respectively. So in Electrical efficiency at 1 g of nanofluid is showed 11% and in 1.5g  nanofluid is  14%.The experimental results have shown that the utilization of nanofluid (Al2O3) as a result of its high thermal conductivity and tiny particle size. The coefficient of heat transfer and Nusselt number increasing with the increase of concentration of nanofluid, It can be concluded that has great impact, especially in Iraq condition where the temperature is normally high and can improve their performance and efficiency by adding nanofluid for cooling system.

Sub-Cooling Auxiliary System for Performance Enhancement of Main Refrigeration System

Mustafa W. Hamadalla; Fawziea M. Hussien; Ahmed J. Hamad

Engineering and Technology Journal, 2015, Volume 33, Issue 8, Pages 1798-1812

In presentwork, a sub-coolingauxiliary system is integrated with vapour compression refrigeration system to predict the performance characteristics and energy saving of the system. An experimental investigation was performed to determine the performance parameters at various operating conditions using two types of refrigerants, R-134a and zeotropic mixed refrigerant R-404A.Investigating the results hasshowed that, the enhancement in performance of the refrigeration system with sub-cooling circuit compared with that for system without sub-cooling for R-134a was about 5% increase in RE, 14% optimization in COPand 2.8% energy saving for different thermal loads applied on the evaporator.While for R-404A, the increase in RE was 4%, the optimization in COP was about 13% and 3.7%energy saving. There is a significant improvement in the performance of the system with R-404A compared with that forR-134a at the same operating conditions.