Earth-contact heat transfer: improvement and application of a novel simulation technique

This paper reports on the improvement and application of a new method for the prediction of earth-contact heat transfer. In previous studies the new method was claimed to be fast, accurate and flexible as a result of incorporating elements of the response factor method into a finite volume technique based numerical model. Initially, a ‘pre-processing’ procedure is required to generate a certain number of hours for use as a time-series by the response factor technique in the second stage of the method. This paper shows that, it is possible to further improve the speed and accuracy of the ‘pre-processing’ procedure without losing the advantage of flexibility that the numerical models provide in the design of such cases. The improvement of the new method is presented which makes use of a ‘time-stepping control scheme’. A simple ‘extrapolation’ technique has been demonstrated previously. This method proved to be accurate and fast in solving the three-dimensional earth-contact heat transfer, which may involve a certain number of heating zones (rooms) interacting with several different temperature profiles. A multi-room configuration is utilised in this study and simulations are performed over one or more years according to the initial ground domain temperature conditions.