thermal conductivity measuring methods can be divided into steady-state method and non-steady-state method by macroscopic mechanism of thermal conductivity.
steady-state method requires long period ,ａnd there are also many other factors which affect measuring accuracy. however, non-steady-state method has the advantage of short measuring time, high accuracy and low requirements for operational environment. especially, the transient hot-wire method has been considered internationally as the best measuring method of thermal conductivity in the research area of thermal conductivity.
measuring principle
the origin of hot-wire method could be traced back to the year 1780 when an american scientistjoseph priestley made the first experiment about heat transfer ability of air. in 1931，stâlhane and pyk, who are the first to adopt transient hot-wire method in measuring the thermal conductivity of solid, powder and liquid, hot-wire method is now widely used in gas, liquid, solid, metal fusion and so on.