Wind effects on soil thermal properties measured by the dual-probe heat pulse method

When a dual-probe heat pulse (DPHP) sensor is installed in soil near the soil-atmosphere interface, the basic assumptions of the infinite line heat source (ILS) model and its improvement, the infinite line heat source model with an adiabatic boundary condition (ILS-ABC) might not be satisfied because of wind. This study aims to explore the effects of wind on DPHP measurements and to compare the performance of the ILS and ILS-ABC models at different values of wind velocity (upsilon) and burial depth (d). Our study shows that the results of laboratory experiments, COMSOL simulations, and field experiments are consistent with each other. For dry sand with d <= 4 mm, the effects of wind is non-negligible at upsilon >= 3.5 m s(-1) and the DPHP method does not provide accurate estimations whether the ILS model or the ILS-ABC model is used. Field experiments are prone to large background temperature fluctuations, which can cause a commonly used linear detrending method to perform poorly. In general, at upsilon < 2.7 m s(-1) in field and d = 5 mm, the ILS-ABC model provides more accurate estimations with relative errors of <15% in thermal conductivity and relative errors of <9% in heat capacity.