A lightweight thermal heat switch for redundant cryocooling on satellites

Abstract

A previously designed cryogenic thermal heat switch for space applications has been optimized for low mass, high structural stability, and reliability. The heat switch makes use of the large linear thermal expansion coefficient (CTE) of the thermoplastic UHMW-PE for actuation. A structure model, which includes the temperature dependent properties of the actuator, is derived to be able to predict the contact pressure between the switch parts. This pressure was used in a thermal model in order to predict the switch performance under different heat loads and operating temperatures. The two models were used to optimize the mass and stability of the switch. Its reliability was proven by cyclic actuation of the switch and by shaker tests.

Fluidic and Mechanical Thermal Control Devices

“…Thermal‐expansion‐based thermal regulators have been made using different materials or their composites, such as copper/Teflon, [ 243 ] stainless steel/beryllium, [ 45 ] thermoplastics, [ 11,244 ] and silica/germanium. [ 245,246 ] Further, they have mainly been used for cryogenics [ 234,235,243 ] and outer space applications.…”

“…[ 245,246 ] Further, they have mainly been used for cryogenics [ 234,235,243 ] and outer space applications. [ 11,244,247 ] One interesting high‐temperature application (up to 700 K) is thermal computing. [ 9,246 ]…”

“…Dietrich et al. [ 11 ] designed thermal‐expansion‐based thermal regulators for outer space applications and demonstrated their reliable and stable operation through long‐term cyclic operation tests (continuously for more than 100 days) and shaker tests. The regulator was made of a composite of ultrahigh‐molecular‐weight polyethylene and thermoplastics.…”

“…Thermal management is a common issue in several applications including cryogenics, [ 10–12 ] energy conversion, [ 13–15 ] caloric refrigeration, [ 16–18 ] microfluidics, [ 19–21 ] biology, chemistry, and pharmacy, [ 22–24 ] buildings, [ 25–28 ] outer space, [ 11,29,30 ] and sensor technologies. [ 31,32 ] Therefore, TCDs for these application areas are being studied theoretically and experimentally.…”

Enhancement of thermal rectification by asymmetry engineering of thermal conductivity and geometric structure for multi-segment thermal rectifier

“…As the size of electronic devices gets smaller and smaller, the heat dissipation by thermal management devices or low-dimensional thermal transport will become a more and more important direction of future development. [39][40][41][42][43][44][45][46] Heat flow control is also very meaningful in many other fields, [47] such as aerospace, [48] refrigeration, [49,50] biology, chemistry, and pharmacy, [51][52][53] buildings, [54][55][56] and so on.…”