Algorithms for Slab-on-Grade Heat Transfer Calculations
Abstract
A major portion of a building's energy consumption can result from earth coupled heat transfer processes. Accurate prediction of heat transfer rates through floors, basements, bermed walls, and earth-covered roofs is a critical first step toward effective control of earth-coupled losses. Algorithms currently in use, both manual and numerical procedures, have fundamental flaws that make them unsatisfactory beyond the level of crude estimates. This report describes the development of two new algorithms for slab-on-grade heat loss calculations. A method suitable for manual use employs a geometric scaling based on the ratio of floor area to perimeter length. A multiple input transfer function method appropriate for implementation in energy analysis programs is built on a seven-node model of the floor/ground system. The models were validated through comparison with the results of an hourly, three-dimensional finite difference program. The results of this study will provide the basis for improving existing estimation methods and building simulation programs for military construction.
Document Details
- Document Type
- Technical Report
- Publication Date
- Sep 01, 1990
- Accession Number
- ADA241567
Entities
People
- Joann Amber
- William P. Bahnfleth
Organizations
- Construction Engineering Research Laboratory