0
RESEARCH PAPERS

The Effect of Cyclic Operation of a Horizontal Ground Loop on Ground Coupled Heat Pump Performance

[+] Author and Article Information
M. Wibbels, K. Den Braven

Department of Mechanical Engineering, University of Idaho, Moscow, ID 83844-0902

J. Sol. Energy Eng 119(1), 13-18 (Feb 01, 1997) (6 pages) doi:10.1115/1.2871801 History: Received September 01, 1994; Revised May 01, 1996; Online February 14, 2008

Abstract

When the required load for single-speed heat pump is a fraction of its capacity, the heat pump must cycle. Multispeed heat pumps are able to vary their speed, and so cycle much less than single-speed heat pumps. The effect of cyclic operation on the heat pump ground loop and the consequent effect on heat pump performance have been examined. To analyze the effect of cyclic operation on heat transfer within the ground, separate finite element models were written for the ground loop and the surrounding soil. The models were used to compare the operation of the ground loop for single-speed and multispeed systems. Results were used to explore the effects of the pipe length, and to examine parameters which alter the effects of cycling. Parameters included pipe size and percent capacity. Results show that cyclic operation will decrease the performance of the heat pump, based solely on the performance of the ground loop (i.e., the total load remains fixed). It is also shown that as the pipe radius is increased, the effect of cyclic operation decreases, again due to the fluid capacity, and that as percent capacity decreases the cycling penalty increases.

Copyright © 1997 by The American Society of Mechanical Engineers
Topics: Surgery , Heat pumps
Your Session has timed out. Please sign back in to continue.

References

Figures

Tables

Errata

Discussions

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related Journal Articles
Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In