Waste heat recovery plays an important role in energy source management. Organic Rankine Cycle (ORC) can be used to recover low-temperature waste heat. In the present work a sample power plant waste heat was used to operate an ORC. First, two pure working fluids were selected based on their merits. Four possible thermodynamic models were considered in the analysis. They were defined based on where the condenser and evaporator temperatures are located. Four main thermal parameters, evaporator temperature, condenser temperature, degree of superheat and pinch point temperature difference were taken as key parameters. Levelized energy cost values and exergy efficiency were calculated as the optimization criteria. To optimize exergy and economic aspects of the system, Strength Pareto evolutionary algorithm II (SPEA II) was implemented. The Pareto frontier solutions were ordered and chose by TOPSIS. Model 3 outperformed all other models. After evaluating exergy efficiency by mixture mass fraction, R245fa [0.6]/Pentane [0.4] selected as the most efficient working fluid. Finally, every component’s role in determining the levelized energy cost and the exergy efficiency and were discussed. The turbine, condenser and evaporator were found as the costliest components.

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Purpose Electronic components’ efficiency is the cornerstone of technology progress. The cooling process used for electronic components plays a main role in their performance. Embedded high-conductivity material and provided microchannel heat sink are two common cooling methods. The former is expensive to implement while the latter needs micro-pump, which consumes energy to circulate the flow. The aim of this study is providing a new configuration and method for improving the performance of electronic components. Design/methodology/approach To manage these challenges and improve the cooling efficiency, a novel method named Hybrid is presented here. Each method's performance has been investigated, and the results are widely compared with others. Considering the micro-pump power, the supply of the microchannel flow and the thermal conductivity ratio (thermal conductivity ratio is defined as the ratio of thermal conductivity of high thermal conductivity material to the thermal conductivity of base solid), the maximum disk temperature of each method was evaluated and compared to others. Findings The results indicated that the Hybrid method can reduce the maximum disk temperature up to 90 per cent compared to the embedded high thermal conductivity at the same thermal conductivity ratio. Moreover, the Hybrid method further reduces the maximum disk temperature up to 75 per cent compared to the microchannel, at equivalent power consumption. Originality/value The information in this research is presented in such a way that designers can choose the desired composition, the limited amount of consumed energy and the high temperature of the component. According to the study of radial-hybrid configuration, the different ratio of microchannel and materials with a high thermal conductivity coefficient in the constant cooling volume was investigated. The goal of the investigation was to decrease the maximum temperature of a plate on constant energy consumption. This aim has been obtained in the radial-hybrid configuration.

Mechanical strength and thermal properties may limit the usage of an electronic component in the high-tech industry. This paper investigated the influence of using CuO nanoparticles in a radial configuration microchannel of a disk from the mechanical and thermal points of view. In this regard, a disk under thermal and mechanical loading had been considered. The cooling setup consisted of a radial configuration microchannel with a constant fluid volume. Water was used as the base fluid and CuO particles were used as the coolant fluid. The results showed that the use of CuO nanoparticles would reduce the maximum disk temperature, the maximum thermal stress, and the maximum stress, as well as the maximum deformation on the body. The increasing number of channels would increase the maximum stress in the object as well. Another remarkable point was that increasing the nanoparticles did not necessarily lead to a more uniform heat distribution in the disk.