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5 Thermal Control Technology of Lunar Lander
after landing, while some of them such as power supply and distribution, thermal
control, and OBDH would work throughout the lifetime of the lunar lander. Only
a few of instruments were working during lunar night. The operation modes of the
lunar lander indifferent phase were different, which also affected the determination
of thermal control design.
In the system design and thermal control design of the lunar lander, the differences
of operation modes of instruments at all phases should be considered. The differences
in temperature requirement in different phases should be treated carefully to minimize
the demand for mass and power through optimization of instruments configuration
and thermal control design.
5.3.2 Technical Characteristics
The mission profile of the lunar lander was complex and the environmental was
harsh. The thermal control subsystem should satisfy special requirements such as
great changes in the external heat flux during LTO, circumlunar orbit, landing and
lunar surface, different operation modes, and survival in lunar night. At the same
time, it should solve the technical difficulties from harsh high-temperature boundary
of landing engine, uncertain landing attitude, and deposition of lunar dust.
According to mission requirements of the lunar lander, the technical characteristics of thermal control subsystem were as follows:
(1) Strong adaptability to changes in external heat flow.
(2) Strong adaptability to changes in operation modes of instruments.
(3) Strong adaptability to changes in gravity conditions by taking full advantage
of lunar gravity to improve capability of heat pipes and fluid loops.
(4) Adaptability to uncertain landing attitude by reasonable configuration of
heat dissipation surface and system prevention of lunar dust to minimize its
influence.
(5) Application of RHU (Radioisotope Heat Unit) for heat source during lunar
night together with active thermal control measures to achieve reasonable
control of RHU.
(6) Use of high temperature insulation material to prevent the high temperature
effects of engine nozzle during landing.
5 Thermal Control Technology of Lunar Lander
after landing, while some of them such as power supply and distribution, thermal
control, and OBDH would work throughout the lifetime of the lunar lander. Only
a few of instruments were working during lunar night. The operation modes of the
lunar lander indifferent phase were different, which also affected the determination
of thermal control design.
In the system design and thermal control design of the lunar lander, the differences
of operation modes of instruments at all phases should be considered. The differences
in temperature requirement in different phases should be treated carefully to minimize
the demand for mass and power through optimization of instruments configuration
and thermal control design.
5.3.2 Technical Characteristics
The mission profile of the lunar lander was complex and the environmental was
harsh. The thermal control subsystem should satisfy special requirements such as
great changes in the external heat flux during LTO, circumlunar orbit, landing and
lunar surface, different operation modes, and survival in lunar night. At the same
time, it should solve the technical difficulties from harsh high-temperature boundary
of landing engine, uncertain landing attitude, and deposition of lunar dust.
According to mission requirements of the lunar lander, the technical characteristics of thermal control subsystem were as follows:
(1) Strong adaptability to changes in external heat flow.
(2) Strong adaptability to changes in operation modes of instruments.
(3) Strong adaptability to changes in gravity conditions by taking full advantage
of lunar gravity to improve capability of heat pipes and fluid loops.
(4) Adaptability to uncertain landing attitude by reasonable configuration of
heat dissipation surface and system prevention of lunar dust to minimize its
influence.
(5) Application of RHU (Radioisotope Heat Unit) for heat source during lunar
night together with active thermal control measures to achieve reasonable
control of RHU.
(6) Use of high temperature insulation material to prevent the high temperature
effects of engine nozzle during landing.