Measurement of thermal conductivity of cured tobacco material

A novel method has been developed to measure the thermal conductivity of leaf-like material (tobacco) in the perpendicular direction to its surface over broad ranges of temperature and moisture with the aim of designing primary processes in the tobacco industry. Reduction in the time a sample is exposed to high temperature and humidity is a decisive factor because tobacco easily changes its nature under these conditions. A closed sample chamber with minimum volume permitted thermal conductivity measurements under these conditions without any significant deterioration in the sample. This method could also be applied to other wet materials that deteriorate easily. The thermal conductivity increased with both temperature and moisture and was regressed into two simple equations. It should become possible to estimate the heat transfer rate at desired temperatures and moistures when more extensive data become available. Consequently, a method for the measurement of the thermal conductivity of tobacco, which is one of the crucial factors in the rational design of primary processes, has been established.