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The quantification of moisture transport in heated wood is relevant to several fields, e.g. for lumber drying and processing and for fire safety risk assessment. We present non-destructive and simultaneous measurements of the moisture content and temperature distributions in pine wood during unilateral exposure to a heat source. The moisture content is measured by a nuclear magnetic resonance setup specifically built for the evaluation of moisture transport in porous materials at elevated temperatures. Temperature profiles are obtained by thermocouples placed at different distances from the exposed surface. While the temperature rises, a peak in the moisture content is formed, which travels towards the unexposed surface. The velocity of the moisture content peak depends on the principal direction in which transport occurs, as confirmed by experiments. Numerical simulations of moisture transport are performed which can qualitatively reproduce the behavior observed in experiments. Moreover, several characteristics, such as the timescale and non-linearity of the moisture peak position, are well captured. The influence of several input parameters, such as the permeability and diffusion coefficient, on the moisture peak dynamics is elaborately explored.

In this study a specialized high-temperature nuclear magnetic resonance (NMR) setup is presented for measuring free moisture in monolithic refractory castables during one-sided heating (100–300 °C). This setup makes use of a high thermal-stability Birdcage-coil for measuring the quantitative moisture content at high-temperatures, while also utilizing a mini-coil for calibrating transverse relaxation changes, as a function of temperature and hydration state, taking place in the sample throughout a drying experiment. We employ a high-temperature correction scheme that calibrates the effects of rising temperatures on the NMR signal. With this configuration, we can non-destructively measure moisture and temperature profiles continuously and achieve a spatial resolution of 2–3 mm for samples as long as 74 mm. After applying the NMR correction, we can extract information about the physical and chemical components of water as they are released from the porous matrix during first heat up. As a model material, we demonstrate the capability of our setup with a conventional castable after it has been cast and cured for 48 h.