Study of a radiative heat exchanger for the E-Test prototype

Abstract

The Einstein Telescope is a highly accurate 3rd generation gravitational wave detector. Thanks to its increased sensitivity, it will be able to observe much more often phenomena so far difficult to detect, such as the fusion of two black holes or will allow the understanding of the Big Bang. However, the sensitivity of this telescope is such that it is subject to disturbances such as thermal noise. To avoid this type of disturbance, the measuring instrument, the mirrors of the Einstein telescope, must be brought to cryogenic temperatures. To meet this technological challenge, a three-dimensional thermal radiator consisting of nested cells could be the solution. This master thesis will study the structure of this radiator by measuring its capacity to exchange energy according to its geometry. In this perspective several quantities are measured such as the heat flux, the temperature variation within the structure and many others. This work makes it possible to decide on the geometric shape of the radiator to be preferred to optimize the heat exchange. It also incorporates the study of a complementary system using helium to accelerate the cooling.