Abstract
Estimation of thermal sensations at the moment when certain objects are touched is an important concern in material evaluation. Heat conduction phenomena can be modeled with the use of thermal contact resistance, not only in cases where imperfect contact is caused by rough and/or uneven contact surfaces, but also in cases where thin films are formed on contact surfaces under certain conditions. First, it has been made clear how thermal contact resistance affects temperatures and rates of temperature change at contact interfaces or at temperature reception sites in the skin. Temperatures at contact interfaces in the absence of thermal contact resistance are defined as substantial ones on the boundary between the skin and the object. However temperatures at the sites having thermal contact resistance are virtual ones that do not really exist. The maximum of the non-dimensional temperature changing rate at the receptive site decreases when thermal contact resistance becomes larger, and it corresponds exactly to the daily experience that object's temperatures are felt nearer to the body temperatures in the presence of thermal contact resistance. Finally, using the universal interface temperature in the absence of thermal contact resistance, we expressed the contact interface temperature that is felt just after touching an object that has thermal contact resistance. We propose calling this temperature "effective contact temperature". It is defined by the initial temperatures, thermal contact resistance and thermal properties of the skin and the object.
