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5 Thermal Control Technology of Lunar Lander
protection of attitude and orbit control engines. For medium-temperature and hightemperature multilayer thermal insulation, they were commonly used together with
low-temperature multi-layer thermal insulation.
The high-temperature insulation shield was a special multi-layer insulation
including high-temperature, medium-temperature and low-temperature multi-layer
insulation. The reflective screens and spacers of the high-temperature multilayer
insulation components were replaced to meet the high temperature conditions of
nozzles with 1300 °C of the landing engine.
6. Thermal Control for Propulsion System
The propulsion system of the lunar lander performed attitude adjustment, orbit
change, and landing by commands. It was crucial to mission of the lunar lander.
In addition, the thermal control of propulsion was complex due to due to complexity
of propulsion system including gas, liquid and valves.
There were in propellant tanks, gas tanks, pipeline and engines in propulsion
system.
(1) In order to ensure that the temperature of propulsion system components meet
the requirement of temperature at low external heat flux, electric heaters were
used for temperature control of propellant and gas tanks, liquid pipeline, gas
pipeline and other components. And a backup was designed for thermal control
loops to improve reliability.
(2) According to distribution of environment temperature, the pipeline was divided
into different sections for thermal control to ensure the effectiveness of temperature control. The pipeline was heated by electric heating tapes, while film-type
electric heating film was used for other components.
(3) Because of large deformation of the gas tanks after filled, the heating device
on surface of tanks should be able to adapt to the deformation.
7. Design of Heating Loops
For instruments such as pyrotechnics, batteries, mechanisms and propulsion, it was
necessary to use electric heating for thermal control. This method had the advantages
of simple structure, convenience and high controlling accuracy, but it should consume
a certain amount of electric power.
In accordance with the form of electric heating devices, they can be classified into
film type electric heaters and electric heating tapes. The electric heating material
is copper-nickel-manganese alloy, and the insulating material is a polyimide film,
where the electric heater is mainly used for propulsion system pipelines. For thermal
control of engine’s head, armored electric heaters could be selected to withstand
higher temperatures.
The heating loops could be controlled by an independent heating controller
according to a preset threshold or ground commands. It was also possible to centralize
the control of the heating circuit to OBDH subsystem or an integrated electronic
subsystem to increase the degree of system integration, whose functions and control
methods were the same as for the individual heating controllers.
5 Thermal Control Technology of Lunar Lander
protection of attitude and orbit control engines. For medium-temperature and hightemperature multilayer thermal insulation, they were commonly used together with
low-temperature multi-layer thermal insulation.
The high-temperature insulation shield was a special multi-layer insulation
including high-temperature, medium-temperature and low-temperature multi-layer
insulation. The reflective screens and spacers of the high-temperature multilayer
insulation components were replaced to meet the high temperature conditions of
nozzles with 1300 °C of the landing engine.
6. Thermal Control for Propulsion System
The propulsion system of the lunar lander performed attitude adjustment, orbit
change, and landing by commands. It was crucial to mission of the lunar lander.
In addition, the thermal control of propulsion was complex due to due to complexity
of propulsion system including gas, liquid and valves.
There were in propellant tanks, gas tanks, pipeline and engines in propulsion
system.
(1) In order to ensure that the temperature of propulsion system components meet
the requirement of temperature at low external heat flux, electric heaters were
used for temperature control of propellant and gas tanks, liquid pipeline, gas
pipeline and other components. And a backup was designed for thermal control
loops to improve reliability.
(2) According to distribution of environment temperature, the pipeline was divided
into different sections for thermal control to ensure the effectiveness of temperature control. The pipeline was heated by electric heating tapes, while film-type
electric heating film was used for other components.
(3) Because of large deformation of the gas tanks after filled, the heating device
on surface of tanks should be able to adapt to the deformation.
7. Design of Heating Loops
For instruments such as pyrotechnics, batteries, mechanisms and propulsion, it was
necessary to use electric heating for thermal control. This method had the advantages
of simple structure, convenience and high controlling accuracy, but it should consume
a certain amount of electric power.
In accordance with the form of electric heating devices, they can be classified into
film type electric heaters and electric heating tapes. The electric heating material
is copper-nickel-manganese alloy, and the insulating material is a polyimide film,
where the electric heater is mainly used for propulsion system pipelines. For thermal
control of engine’s head, armored electric heaters could be selected to withstand
higher temperatures.
The heating loops could be controlled by an independent heating controller
according to a preset threshold or ground commands. It was also possible to centralize
the control of the heating circuit to OBDH subsystem or an integrated electronic
subsystem to increase the degree of system integration, whose functions and control
methods were the same as for the individual heating controllers.