Browsing by Author "Herath, HMDP"

Now showing 1 - 4 of 4

item: Conference-Full-text
Design and analysis of a mems based transdermal drug delivery system
(IEEE, 2020-07) Perera, KNM; Awantha, WVI; Wanasinghe, AT; Herath, HMDP; Paththinige, SSHG; Ekanayaka, L; Amarasinghe, YWR; Weeraddana, C; Edussooriya, CUS; Abeysooriya, RP
The design and analysis of a Micro Electromechanical System-based (MEMS-based) Transdermal Drug Delivery System are presented in the research article. A conceptual design for the delivery of Levodopa was proposed by the authors. Major components of the system were identified as a microfluidic pump, microneedle array and the microfluidic channels connecting the system. The working principles of these components were selected according to the persisting requirements and design considerations. Simulations were conducted to evaluate the performance and to optimize the design of the system. A fabrication method for the system was proposed by the authors as a stacked layer. The results of the simulations conducted were presented. The simulations show positive results with the performance of the system and do not suggest a mode of mechanical failure of the system at the given boundary conditions. The paper concludes with recommendations for future work.
item: Conference-Extended-Abstract
Investigation on the effect of different channel geometries of thermal wheel for energy transfer efficiency
(2021-09-06) Polgolla, AMCK; Herath, HMDP; Wickramasinghe, MDA; Wijewardane, MA; Ranasinghe, RACP
Inside buildings, heating, ventilation, and air conditioning systems are utilized to provide a comfortable environment. However, they account for a significant percentage of overall total energy consumption: in the United States, they account for about 50% of building final energy consumption and 20% of total energy consumption. [1]. The installation of a heat exchanger between the exhaust and fresh air streams is critical, owing to the significant energy savings. [2], [3]. Thermal wheels have recently gotten a lot of attention because of their high efficiency and low-pressure loss when compared to other energy recovery solutions [4]. The goal of this research is to give a comprehensive study and optimization of Thermal wheel design, with the goal of enhancing sensible effectiveness while reducing pressure loss based on channel shape.
item: Article-Full-text
Numerical model-based prediction of performance of single stage traveling wave thermo-acoustic engines
(Elsevier, 2021) Herath, HMDP; Wijewardane, MA; Ranasinghe, RACP
In the recent past, attraction towards the new power generation technologies and thermal energy recovery have become exponentially increasing due to the environmental and economic concerns. Thermo-acoustic generation has been identified as an attractive novel technology for low-grade energy recovery and power generation. Only moving component of the thermo-acoustic generation system is the linear alternator, which is used to convert acoustic energy into electrical energy, and hence, it leads to increase the reliability of thermo-acoustic systems with comparative to the other power generation technologies. Traveling wave thermo-acoustic generators have higher efficiencies with respective to its counterpart, standing-wave thermo-acoustic generators. Traveling wave thermo-acoustic generators are much economical and less complex as it can be operated with ambient air at atmospheric pressure conditions as the working fluid. During this study, a single stage traveling-wave thermo-acoustic engine was modeled and validated using available test results in the literature. The validated model was used to predict the optimum working conditions for a traveling wave thermo-acoustic engine to obtain the maximum efficiency from the engine. Results show that the increment of temperature in hot heat exchanger tends to increase the efficiency of the system.
item: Article-Full-text
Working fluid selection of Organic Rankine Cycles
(Elsevier, 2020) Herath, HMDP; Wijewardane, MA; Ranasinghe, RACP; Jayasekera, JGAS
Organic Rankine Cycles (ORCs) are identified as one of the best candidates to generate electricity from low-grade heat sources. ORCs operate on low temperatures and low pressures with comparative to conventional Rankine Cycles. Therefore, organic fluids or refrigerants can be used as the working fluids for ORC applications, instead of water, which is more suitable for high-pressure and high-temperature applications. The performance and the system design of the ORC system are entirely dependent on the working fluid, and hence, working fluid selection for ORCs is utmost important for a particular application, i.e. solar thermal, geothermal or waste heat recovery. Performance of the ORCs for seven (07) working fluids: R-134a, R-245fa, Benzene, Methanol, Ethanol, Acetone and Propane (R-290) have been studied during this work. Results of the study show that Benzene and Methanol based ORC systems perform more efficiently with comparative to the other working fluids considered in the analysis and, they require lower fluid mass flowrates per unit of power generation relative to other fluids used in the analysis.