The large horizontal ultra-low temperature heat sink

based on liquid helium cooling

could firstly realize heat sink surface temperature below 10K in China

and is mainly applied to spacecraft-thruster vacuum plume effects' experimental study and the thermal vacuum test of satellite simultaneously.In order to minimize heat loss

the main structure of heat sink frame was removed

and the liquid helium heat sink was enclosed by a liquid nitrogen heat sink.Both of them were designed integrally so that the liquid nitrogen heat sink is not only the anti-radiation panel for liquid helium heat sink

but also the frame brace.To increase the pumping speed of heat sink

a plume adsorption pump was developed and mounted on the end of the vacuum chamber.At the experiment of vacuum plume

vacuum plume adsorption pump and liquid nitrogen heat sink were cooled by liquid helium and liquid nitrogen

respectively.The analysis was conducted for key parameters of heat sink

such as estimating the liquid nitrogen

liquid helium consumption in pre-cooling process and steady-state condition

and comparing the relationship between pumping speed of heat sink and working fluid temperature.The results show that pumping speed of the heat sink for nitrogen can reach 107L/s magnitude.