Experimental Study of Heat Transfer Enhancement in Solar Tower Receiver Using Internal Fins

The receiver is an important element in solar energy plants.The principal receiver’s tubes in power plants are devised to work under extremely severe conditions,including excessive heat fluxes.Half of the tube’s circumference is heated whilst the other half is insulated.This study aims to improve the heat transfer process and reinforce the tubes’structure by designing a new receiver;by including longitudinal fins of triangular,circular and square shapes.The research is conducted experimentally using Reynolds numbers ranging from 28,000 to 78,000.Triangular fins have demonstrated the best improvement for heat transfer.For Reynolds number value near 43,000 Nusselt number(Nu)is higher by 3.5%and 7.5%,sequentially,compared to circular and square tube fins,but varies up to 6.5%near Re=61000.The lowest friction factor is seen in a triangular fin receiver;where it deviates from circular fins by 4.6%,and square fin tubes by 3.2%.Adding fins makes the temperature decrease gradually,and in the case of no fins,the temperature gradient between the hot tube and water drops sharply in the planed tube by 7%.

Modeling optimal long-term investment strategies of hybrid wind-thermal companies in restructured power market

In this paper,a novel framework for the estimation of optimal investment strategies for combined wind-thermal companies is proposed.The medium-term restructured power market was simulated by considering the stochastic and rational uncertainties,the wind uncertainty was evaluated based on a data mining technique,and the electricity demand and fuel price were simulated using the Monte Carlo method.The Cournot game concept was used to determine the Nash equilibrium for each state and stage of the stochastic dynamic programming(DP).Furthermore,the long-term stochastic uncertainties were modeled based on the Markov chain process.The longterm optimal investment strategies were then solved for combined wind-thermal investors based on the semi-definite programming(SDP)technique.Finally,the proposed framework was implemented in the hypothetical restructured power market using the IEEE reliability test system(RTS).The conducted case study confirmed that this framework provides robust decisions and precise information about the restructured power market for combined wind-thermal investors.

IoT Technologies for Tackling COVID-19 in Malaysia and Worldwide:Challenges, Recommendations, and Proposed Framework

The Coronavirus(COVID-19)pandemic is considered as a global public health challenge.To contain this pandemic,different measures are being taken globally.The Internet of Things(IoT)has been represented as one of the most important schemes that has been considered to fight the spread of COVID-19 in the world,practically Malaysia.In fact,there are many sectors in Malaysia would be transformed into smart services by using IoT technologies,particularly energy,transportation,healthcare sectors.This manuscript presents a comprehensive review of the IoT technologies that are being used currently in Malaysia to accelerate the measures against COVID-19.These IoT technologies including smart thermal detection,surveillance network,and healthcare delivery technologies.In addition,the most potential IoT technologies developed by other nations to tackle COVID-19 are reviewed,including tracking and tracing systems based on IoT,adoption of IoT technologies in hospitals,and self-monitoring devices based on IoT.For these technologies to be incorporated in Malaysia,the main challenges with possible recommendations are discussed in this manuscript.Finally,this work proposes a conceptual framework to accelerate the battle pace with spread of COVID-19 in Malaysia by integrating IoT technologies used in fighting the outbreak of COVID-19 globally.