Measuring the Thermal Conductivity of Humid Air over a Broad Temperature and Water Content Range

The knowledge of the thermal conductivity of humid air between 0 and 100 °C and 0 and 100% relative humidity is of great interest for various applications. However, direct measurement of the thermal conductivity of gaseous substances is challenging. Using an adapted version of the 3-omega method, we show that direct measurement is possible within a reasonable error limit.