Analytical Modeling and Optimization of a Thermoelectric Heat Conversion System Operating Betweeen Fluid Streams

• Main Author: Taylor, Stephen H.
• Format: Others
• Published: BYU ScholarsArchive 2011
• Subjects: energy conversion; thermoelectric; waste heat; payback time; pressure drop; heat sink; optimization; Mechanical Engineering
• Online Access: https://scholarsarchive.byu.edu/etd/2813; https://scholarsarchive.byu.edu/cgi/viewcontent.cgi?article=3812&context=etd

Analytical, closed-form solutions governing thermoelectric behavior are derived. An analytical model utilizing a thermal circuit is presented involving heat transfer into, through, out of, and around a thermoelectric device. A nondimensionalization of the model is presented. Linear heat transfer theory is applied to the model to obtain a series of closed form equations predicting net power output for the thermoelectric device. Fluid streams flowing through shrouded heat sinks with square pin fins are considered for the thermal pathways to and from the device. Heat transfer and pressure drop are characterized in a manner conducive to an analytical model using previously published experimental results. Experimental data is presented which validates and demonstrates the usefulness of the model in predicting power output for commercially available thermoelectric generators. A specific design for a thermoelectric power harvester is suggested consisting of a pattern of thermoelectric generators. An economic model for calculating payback time is developed. An optimization process is demonstrated that allows for the payback time of such a system to be minimized through optimization of the physical design of the system. It is shown that optimization of the thermal pathways dramatically reduces payback time. Optimized design of a system is discussed in light of theoretical cases with feasible payback times.