Session
Weekday Poster Session 5
Location
Utah State University, Logan, UT
Abstract
As the cost for access to space continues to lower, there is a trend toward higher power compact payloads in CubeSats. This leads to thermal and power limitations to maintain payloads in appropriate operating temperatures. The problem is two-fold: 1) the high heat flux due to compact design and 2) the limited radiator area for heat rejection. The high heat flux ( > 2-3W/cm2) demands a two-phase solution to remove heat effectively without large temperature gradients ( < 5°C) and is ideally passive for reduced complexity and cost. CubeSats also inherently have a limited radiator area. To make the most of the area, radiators are designed to be isothermalized at the highest temperature to reject as much heat as possible. Higher operating temperatures allow more heat to be rejected through the limited radiator area but is restricted by payload operating temperatures; thus, a deployable radiator is desirable to increase radiator area and allow for greater heat rejection. Conduction-only solutions such as thermal straps have high thermal resistance and do not allow for iso thermalization of the radiator. Thus, a two-phase approach is desirable.
The solution to this two-fold problem is the utilization of an additively manufactured Loop Heat Pipe (LHP) with a deployable radiator. Additive manufacturing enables order of magnitude lower cost and lead time than traditional designs and allows for advanced miniaturized complex geometries for mass and volume savings. It offers the ability to be built with the CubeSat bus as a single-part assembly, serving as an integral thermo-structural member of the spacecraft. Additionally, LHPs allow for two-phase heat transfer across deployment mechanisms, allowing for isothermalization of both integrated and deployable radiators, unlocking the CubeSat Thermal Capacity.
Additive Manufactured Loop Heat Pipe with Deployable Radiator to Unlock CubeSat Thermal Capacity
Utah State University, Logan, UT
As the cost for access to space continues to lower, there is a trend toward higher power compact payloads in CubeSats. This leads to thermal and power limitations to maintain payloads in appropriate operating temperatures. The problem is two-fold: 1) the high heat flux due to compact design and 2) the limited radiator area for heat rejection. The high heat flux ( > 2-3W/cm2) demands a two-phase solution to remove heat effectively without large temperature gradients ( < 5°C) and is ideally passive for reduced complexity and cost. CubeSats also inherently have a limited radiator area. To make the most of the area, radiators are designed to be isothermalized at the highest temperature to reject as much heat as possible. Higher operating temperatures allow more heat to be rejected through the limited radiator area but is restricted by payload operating temperatures; thus, a deployable radiator is desirable to increase radiator area and allow for greater heat rejection. Conduction-only solutions such as thermal straps have high thermal resistance and do not allow for iso thermalization of the radiator. Thus, a two-phase approach is desirable.
The solution to this two-fold problem is the utilization of an additively manufactured Loop Heat Pipe (LHP) with a deployable radiator. Additive manufacturing enables order of magnitude lower cost and lead time than traditional designs and allows for advanced miniaturized complex geometries for mass and volume savings. It offers the ability to be built with the CubeSat bus as a single-part assembly, serving as an integral thermo-structural member of the spacecraft. Additionally, LHPs allow for two-phase heat transfer across deployment mechanisms, allowing for isothermalization of both integrated and deployable radiators, unlocking the CubeSat Thermal Capacity.
