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Effects Of Back Reflectors And Thin Metal Covers On The Performance Of Near-Field Thermophotovoltaic Devices, Mehran Habibzadeh

Electronic Theses and Dissertations

Highly efficient energy harvesting devices that can recover a large amount of waste energy are of significant interest. Thermophotovoltaics (TPVs) are solid-state devices that can convert thermal energy radiated by a heated emitter into electrical power through the process of photovoltaic effect. In a TPV system, heat is converted to electricity by using a high-temperature emitter to radiate photons, which are then absorbed by a photovoltaic (PV) cell, generating electron-hole pairs and producing electrical power.

TPV devices have the advantages of producing High efficiency and being lightweight with low maintenance cost and zero pollution. However, these devices have not been …

Model Predictive Control Of Energy Systems For Heat And Power Applications, Chethan Ramakrishna Reddy

Dissertations, Master's Theses and Master's Reports

Building and transportation sectors together account for two-thirds of the total energy consumption in the US. There is a need to make these energy systems (i.e., buildings and vehicles) more energy efficient. One way to make grid-connected buildings more energy efficient is to integrate the heating, ventilation and air conditioning (HVAC) system of the building with a micro-scale concentrated solar power (MicroCSP) sys- tem. Additionally, one way to make vehicles driven by internal combustion engine (ICE) more energy efficient is by integrating the ICE with a waste heat recovery (WHR) system. But, both the resulting energy systems need a smart …

Experimental Characterization Of Thermal-Hydraulic Performance Of A Microchannel Heat Exchanger For Waste Heat Recovery, James Yih, Hailei Wang

Mechanical and Aerospace Engineering Faculty Publications

Given size and performance advantages, microchannel heat exchangers are becoming increasingly important for various energy recovery and conversion processes. In this study, detailed experimental measurements were conducted to characterize flow and heat transfer performance of a microchannel heat recovery unit (HRU) manufactured using standard photochemical etching and diffusion bonding processes. According to the global flow and temperature measurement, the HRU has delivered the predicted thermal performance under various oil and air flow rates. As expected, the heat transfer effectiveness varies between 88% and 98% for a given air and oil flow rates while it increases with air inlet temperature due …

Performance Analysis Of An Exhaust Heat Recovery System Utilizing Heat Pipes, Metal Foam, And Thermoelectric Generators, Michael Resciniti

Honors Program Projects

Developing efficient thermoelectric generator systems to recover wasted thermal energy from automotive exhaust gasses has potential to improve engine efficiency and reduce carbon emissions. Due to their high thermal transfer efficiency, heat pipes have been used to assist thermoelectric generator systems in these applications. To aid in additional heat transfer, metal fins are often used with heat pipes to take advantage of extended-surface heat transfer. This paper proposes a thermoelectric generator system that employs metal foam as an extended-surface heat transfer aid used in conjunction with heat pipes. Three test conditions were simulated to evaluate the system performance in terms …

Performance Analysis Of An Exhaust Heat Recovery System Utilizing Heat Pipes, Metal Foam, And Thermoelectric Generators, Michael Resciniti

Scholar Week 2016 - present

This paper highlights a new type of modified heat pipe assisted thermoelectric generator system for automobile exhaust waste heat recovery. This system employs the use of metal foam as a heat transfer aid to increase the thermal energy transferred through the system. In this system, heat pipes are inserted into a metal foam block that is exposed to the exhaust gas stream. The metal foam increases heat transfer in a similar way that fins increase heat transfer. To confirm that this system provides a greater conversion of thermal energy, an experimental prototype was built and tested. Tests were conducted with …

Thermodynamic And Economic Analysis Of Several Hybrid Multigeneration Cycles And Waste Heat Recovery Systems Driven By Concentrated Solar Tower, Kasra Mohammadi

Doctoral Dissertations

In recent decades, growth in the world population, economic and living standards have been responsible for substantial increases in global energy consumption. Moreover, exploitation of fossil fuels to supply energy demands has led to global climate change, which is expected to have far-reaching and long-lasting consequences on the planet. These factors have motivated the importance and necessity of developing more efficient ways for energy conservation and generation that avoid the production of greenhouse gases that contribute to climate change. One method to address these issues is to develop combined production such as multigeneration for simultaneous production of electricity, cooling, fresh …

Modelling, Design, And Optimization Of Membrane Based Heat Exchangers For Low-Grade Heat And Water Recovery, Soheil Soleimanikutanaei

FIU Electronic Theses and Dissertations

Transport Membrane Condenser (TMC) is an innovative technology based on the property of a nano-scale porous material which can extract both waste heat and water from exhaust gases. This technology tremendously improves the efficiency of boilers and gas/coal combustors by lowering waste heat and increasing water recovery. Contaminants in the flue gases, such as CO2, O2, NOx, and SO2 are inhibited from passing through the membrane by the membrane’s high selectivity. The condensed water through these tubes is highly pure and can be used as the makeup water for many industrial applications. The goal of this research is to investigate …

Waste Heat Recovery From Distributed Rack-Based Fuel Cells Using Thermoelectric Generators, Khosrow Ebrahimi, Alfonso Ortega, Calvin Li, Kazuaki Yazawa, Sean James

Mechanical and Biomedical Engineering Faculty Publications and Presentations

Off-grid power generation has been demonstrated in data centers through the deployment of site-specific centralized power plants utilizing gas turbine or fuel cell-based power generation. Because power is centrally generated, power distribution requires a high voltage power grid within the data center with its ancillary storage and conditioning requirements and equipment. An alternative approach is a completely decentralized distributed power generation system in which fuel cells deployed within individual server racks provide power localized to that rack only. Among other advantages, such an approach also greatly increases the ability to modulate and control power to individual rack units. Because the …

Parametric And Design Analysis On Thermoelectric Generators, Shouyuan Huang

Open Access Theses

In facing the limited energy source reserves and environmental problems, thermoelectric generators (TEGs) are one of the promising waste heat recovery systems. The modern TEGs for exhaust stream (e.g. from automobiles) can improve the fuel economy by around 5%, taking advantage of the recent developed thermoelectric (TE) materials.

In this work, we aimed at designing a TEG as an add-on module for a gas-phase heat exchanger with maximized power output, and without negative impact (e.g. maintaining a minimum heat dissipation rate from the hot side). We first developed a parametric optimization algorithm using response surface method (RSM) and genetic algorithm …

Waste Heat Recovery Options In A Large Gas-Turbine Combined Power Plant, Ularee Upathumchard

Open Access Theses

This study focuses on power plant heat loss and how to utilize the waste heat in energy recovery systems in order to increase the overall power plant efficiency. The case study of this research is a 700-MW natural gas combined cycle power plant, located in a suburban area of Thailand. An analysis of the heat loss of the combustion process, power generation process, lubrication system, and cooling system has been conducted to evaluate waste heat recovery options. The design of the waste heat recovery options depends to the amount of heat loss from each system and its temperature. Feasible waste …

Power Generation And Control Of Mechatronics Systems - Theory And Test, Kelly Austin

All Theses

An integrated, multi-disciplined approach to engineering design is a broad definition of mechatronics. Though some mechatronics proponents differ in their definitions of the topic, an interdisciplinary approach to engineering is taken by many industries which should be reflected on campus in the approach to engineering education. In this thesis, two mechatronics systems are investigated. A laboratory experiment is developed for use in the mechanical engineering program at Clemson University, and a thermoelectric power generation from diesel engine exhaust heat is investigated as an automotive industry application.
An electromagnet excited masspendulum system with attached spring and damper elements is introduced as …