Type
Text
Type
Dissertation
Advisor
Hwang, David | Longtin, Jon P | Mamalis, Sotirios | Sampath, Sanjay.
Date
2015-12-01
Keywords
Engineering | Additive Manufacturing, Dispenser Printing, Laser Processing, Thermal Spray, Thermoelectirc Generators, Waste-Heat Energy Harvesting
Department
Department of Mechanical Engineering.
Language
en_US
Source
This work is sponsored by the Stony Brook University Graduate School in compliance with the requirements for completion of degree.
Identifier
http://hdl.handle.net/11401/76455
Publisher
The Graduate School, Stony Brook University: Stony Brook, NY.
Format
application/pdf
Abstract
Thermoelectric generators (TEGs) are solid-state devices that convert heat directly into electricity. They are well suited for waste-heat energy harvesting applications as opposed to primary energy generation. Commercially available thermoelectric modules are flat, inflexible and have limited sizes available. State-of-art manufacturing of TEG devices relies on assembling prefabricated parts with soldering, epoxy bonding, and mechanical clamping. Furthermore, efforts to incorporate them onto curved surfaces such as exhaust pipes, pump housings, steam lines, mixing containers, reaction chambers, etc. require custom-built heat exchangers. This is costly and labor-intensive, in addition to presenting challenges in terms of space, thermal coupling, added weight and long-term reliability. Additive manufacturing technologies are beginning to address many of these issues by reducing part count in complex designs and the elimination of sub-assembly requirements. This work investigates the feasibility of utilizing such novel manufacturing routes for improving the manufacturing process of thermoelectric devices. Much of the research in thermoelectricity is primarily focused on improving thermoelectric material properties by developing of novel materials or finding ways to improve existing ones. Secondary to material development is improving the manufacturing process of TEGs to provide significant cost benefits. To improve the device fabrication process, this work explores additive manufacturing technologies to provide an integrated and scalable approach for TE device manufacturing directly onto engineering component surfaces. Additive manufacturing techniques like thermal spray and ink-dispenser printing are developed with the aim of improving the manufacturing process of TEGs. Subtractive manufacturing techniques like laser micromachining are also studied in detail. This includes the laser processing parameters for cutting the thermal spray materials efficiently by optimizing cutting speed and power while maintaining surface quality and interface properties. Key parameters are obtained from these experiments and used to develop a process that can be used to fabricate a working TEG directly onto the waste-heat component surface. A TEG module has been fabricated for the first time entirely by using thermal spray technology and laser micromachining. The target applications include automotive exhaust systems and other high-volume industrial waste heat sources. The application of TEGs for thermoelectrically powered sensors for Small Modular Reactors (SMRs) is presented. In conclusion, more ways to improve the fabrication process of TEGs are suggested. | 188 pages
Recommended Citation
Tewolde, Mahder, "Fabrication of Thermoelectric Devices Using Additive-Subtractive Manufacturing Techniques: Application to Waste-Heat Energy Harvesting" (2015). Stony Brook Theses and Dissertations Collection, 2006-2020 (closed to submissions). 2375.
https://commons.library.stonybrook.edu/stony-brook-theses-and-dissertations-collection/2375