色黄性日韩在线,国产精品无码久久久久,三年片免费观看大全国语,国产精品免费久久久久影院 ,亚洲一区二区偷拍精品,日韩精品孕妇电影院,超碰精品人妻在线,久久久久久久久久精品

產(chǎn)品列表PRODUCTS LIST

首頁 > 測試服務(wù) > TC3000 Thermal Conductivity
TC3000 Thermal Conductivity
點擊次數(shù):2268 更新時間:2014-09-01

 

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.