ISSN Online: 2377-424X
ISBN Print: 0-89116-559-2
International Heat Transfer Conference 8
A CRITICAL ANALYSIS OF THE CALORIMETRIC METHOD FOR DETERMINING THE HEAT FLUX IN SOILS
Abstract
The calorimetric method for determining the heat flux in soils in situ assumes heat transfer by conduction only and neglects heat transfer associated with moisture movement. In this paper an analysis of the influence of the latter is presented by comparing the orders of magnitude of the terms in the complete heat balance equation.
It is concluded that under field conditions the following phenomena can impede the application of the calorimetric method: (1) Transfer of sensible heat by liquid water movement in saturated or nearly saturated soil layers. (2) Extraction of latent heat from a soil layer by net evaporation.
The order of magnitude calculations can also be applied to obtain estimates of the relative importance of the terms in the coupled partial differential equations describing simultaneous heat and moisture transfer in soils.
It is concluded that under field conditions the following phenomena can impede the application of the calorimetric method: (1) Transfer of sensible heat by liquid water movement in saturated or nearly saturated soil layers. (2) Extraction of latent heat from a soil layer by net evaporation.
The order of magnitude calculations can also be applied to obtain estimates of the relative importance of the terms in the coupled partial differential equations describing simultaneous heat and moisture transfer in soils.