Hot-Wire Measurements in Cryogenic Environment

The hotwire anemometry is a well known measurement technique used in several applications to determine flow velocity and to investigate flow quality. Using this measurement technique in a cryogenic environment is not very common and therefore the knowledge about it is very limited. The European Transonic Windtunnel, as cryogenic high Reynolds number test facility, is establishing the hotwire measurement technique to support flow quality measurements required by future laminar flow test campaigns. The present paper describes the challenges of such a system setup in ETW, its application and presents first results gathered in the pilot facility of the European Transonic Windtunnel. Thereby the main objective of this paper is to give a general overview about the first achieved results and to discuss the different influencing parameters on the hotwire output signal over the complete operational envelope of ETW/PETW.