A. Rezania

New Configurations of Micro Plate-Fin Heat Sink to Reduce Coolant Pumping Power

The thermal resistance of heat exchangers has a strong influence on the electric power produced by a thermoelectric generator (TEG). In this work, a real TEG device is applied to three configurations of micro plate-fin heat sink. The distance between certain microchannels is varied to find the optimum heat sink configuration. The particular focus of this study is to reduce the coolant mass flow rate by considering the thermal resistances of the heat sinks and, thereby, to reduce the coolant pumping power in the system. The three-dimensional governing equations for the fluid flow and the heat transfer are solved using the finite-volume method for a wide range of pressure drop laminar flows along the heat sink. The temperature and the mass flow rate distribution in the heat sink are discussed. The results, which are in good agreement with previous computational studies, show that using suggested heat sink configurations reduces the coolant pumping power in the system.

Thermal Effect of Ceramic Substrate on Heat Distribution in Thermoelectric Generators

In thermoelectric generators (TEG), poor system design and load matching, which make the system less efficient, have been limiting factors in achieving high conversion efficiency. In this work, to consider the effect of the inlet plenum arrangement and the laminar coolant flow temperature variation in the heat sink, a parallel microchannel heat sink is applied to a real TEG. The focus of this study is a discussion of the temperature difference variation between the cold/hot sides of the TEG legs versus the variation of the thermal conductivity of the ceramic substrate and the thickness of the substrate on the hot side. While the imposed heat flux on the TEG is homogeneously constant, different pressure drops are applied along the microchannel heat sink. The three-dimensional governing equations for the fluid flow and heat transfer are solved using the finite-volume method. The results show that the temperature difference is affected remarkably by the pressure drops in the heat sink, the thermal conductivity of the ceramic substrate, and the thickness of the substrate on the hot side.

Optimal Arrangement of Thermoelectric Modules for Recovering the Waste Heat of Damavand Power Plant using Mutable Smart Bee and Neuro-Fuzzy System

In current research, the authors intend to find the optimal arrangement of planar thermoelectric modules to maximize the generated electricity and minimize the maintenance cost of a power system called Damavand power plant. Optimal arrangement is done by mounting a number of thermoelectric modules within the condenser in order to recover the waste heat of the thermal system. For this purpose, firstly, an adaptive neuro fuzzy inference system ANFIS is utilized to model the generated power of thermoelectric module and the corresponding maintenance cost. Thereafter, Gambit and Fluent softwares are applied to evaluate the temperature rate through the length of thermoelectric component. Given the derived information, the authors use a recent spotlighted metaheuristic called mutable smart bee algorithm MSBA to optimally arrange the thermoelectric modulus for recovering the waste heat of Damavand power plant. Based on the obtained numerical results, it is proven that the proposed frame work is completely capable of finding a practical arrangement of thermoelectric cells within the entry of condenser component.

Experimental Investigation of a Natural Circulation Solar Domestic Water Heater Performance under Standard Consumption Rate

This paper reports experimental studies on the performance of a natural circulation solar water heater considering the weather condition of a city in north of Iran. The tests are done on clear and partly cloudy days. The variations of storage tank temperature due to consumption from the tank, daily consumption influence on the solar water heater efficiency, and on the input temperature of the collector are studied and the delivered daily useful energy has been obtained. The results show that by withdrawing from storage tank, the system as well as its collector efficiency will increase. Considering the value of the coefficient and τα, which are obtained experimentally as 6.03 and 0.83 respectively, average monthly total load that is covered by this solar water heating system is estimated.

Thermoelectric energy conversion : basic concepts and device applications

Following an initial chapter that introduces the fundamentals and principles of thermoelectricity, subsequent chapters discuss the synthesis and integration of various bulk thermoelectric as well as nanostructured materials. The book then goes on to discuss characterization techniques, including various light and mechanic microscopy techniques, while also summarizing applications for thermoelectric materials, such as microand nano-thermoelectric generators, wearable electronics and energy conversion devices.