Performance of Thermoactive Foundations for Commercial Buildings

Abstract

A transient threedimensional numerical solution is developed to analyze the thermal performance of thermoactive foundations used to heat and cool commercial buildings. Using laboratory testing data, the numerical solution is validated and used to carry out a sensitivity analysis to assess the most important design and operating parameters that affect the thermal performance of thermoactive foundations. It is found that the foundation depth, the shank space, the fluid flow rate, and the number of Utube loops in each foundation pile are the main parameters that affect the thermal performance of a thermoactive foundation system. Based on the validated numerical solution, thermal response factors for a thermoactive foundation are developed, and implemented into a detailed building energy simulation program. These thermal response factors are then used to estimate the impact of installing thermoactive foundations on the total energy use of typical office buildings in representative US climates.