Degree Type

Dissertation

Date of Award

1994

Degree Name

Doctor of Philosophy

Department

Agricultural and Biosystems Engineering

First Advisor

Dwaine S. Bundy

Abstract

This research details the analysis of a ground-coupled heat pump system which utilizes a 20,000 gallon well-water storage tank as a source of heating and cooling. It addresses the feasibility of such a system and discusses the system in terms of energy efficiency--first law conservation analysis. The potential use of this type of system for the control of sensitive thermal environments involving swine is also evaluated;The goal of this research was to investigate ISU's SNMRC heat pump system. Specific objectives were: (1) To evaluate the system in terms of heat exchanger and heat pump efficiencies. (2) To develop a mathematical model which simulates the heat pump system, accounting for energy gains/losses throughout, and which is capable of predicting energy availability based upon various heat exchanger coil lengths, cistern sizes, heat pump sizes and well water flow rates. (3) To evaluate the system in terms of its ability to provide energy. (4) To investigate the potential of the heat pump system for control of sensitive thermal environments for swine;Investigations of this system were conducted both experimentally, and numerically through a mathematical model. Experimentally, the tank heat exchanger efficiencies were determined to average 0.71 during the heating mode and 0.99 during the cooling mode. From the mathematical model, the efficiencies were 0.72 and 1.00 for the heating and cooling modes, respectively. The model predicted heat pump coefficients of performance from 3.5 to 4.8 for heating and 2.4 to 4.0 for cooling. Results indicated that appropriately sized heat pump, heat exchanger coil and cistern were a source of supplemental heating, are energy conservative and offer control of sensitive thermal environments for specific applications involving swine.

DOI

https://doi.org/10.31274/rtd-180813-9744

Publisher

Digital Repository @ Iowa State University, http://lib.dr.iastate.edu/

Copyright Owner

James D. Leary

Language

en

Proquest ID

AAI9503576

File Format

application/pdf

File Size

130 pages

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