MSc thesis seminar: "Design and thermal analysis of a cryogenic radiator using V Groove effect for space telescope application" by Gauthier Jary

Abstract: This master’s thesis presents the design,
analysis, and realization of a cryogenic
radiator using V-Groove technology, from initial
estimates and conceptual design to elaboration
of both a numerical and physical model
in order to create a baseline for future investigations
of the key parameters of the VGroove
technology. The approach combined
heat transfer theory and the V-Groove effect
with simplified digital models, nodal descriptions,
analytical formulas, Monte Carlo ray tracing,
and deterministic finite element methods
and laboratory emissivity measurements. The
design process balanced performance optimization
and budget constraints. The final physical
model, approximately 30x40 cm, includes three
rounded radiator stages optimized through digital
simulations to cool a 10 mW heat load down
to 80 K. Its last stage features an innovative
high-emissivity coating used in current space
missions, ensuring flight-like thermal behavior.
Each stage is separated by custom-made PTFE
insulating supports, with dedicated multi-layer
insulation for the mounting base and instrument
interface. Despite its compact size and the
71% parasitic heat load on the cold patch, the
model’s projected performance matches other
cryogenic radiant coolers for the same final
temperature. Equipped with instrumentation
for cryostat integration, the model will undergo
tests at the CNES laboratory to validate its performance
against numerical predictions from
Python-based calculations and finite element
simulations. These tests will serve as proof
of concept, enabling further modifications and
sensitivity studies, such as additional stages or
new surface coatings.