15.9 Test of Plume Effect on Thermal Control
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15.9 Test of Plume Effect on Thermal Control
15.9.1 Test Objective
The test objective of plume effect on thermal control was to acquire the resistant
ability to ablation and erosion of the engine plume for the thermal control material
on landing gears, bottom plate and protrusions on bottom plate during soft landing
by simulation of plume condition, and to provide important reference for thermal
design of landing gears and bottom plate of the lunar lander.
15.9.2 Test Constraints and Methodology
When the test system for plume effect on thermal control was designed, the following
constraints should be considered.
(1) It could simulate the vacuum environment while the engine was firing on orbit.
(2) It could simulate heat flow while the engine was firing on orbit.
(3) It could simulate the real thermal state
(4) It could simulate the effect of engine plume on thermal control.
Due to the limitation of vacuum test conditions, the plume of large engine was difficult
to simulate on the ground. Therefore, small engine could be applied for the equivalent
heat flow simulation. The small engine was firing in high vacuum simulation system,
while test articles covered with thermal control material was placed at appropriate
position in the plume of small engine in order to simulate the plume effect of large
engine on thermal control material.
15.9.3 Design of Test System
The test system of plume effect on thermal control was composed of vacuum
simulation subsystem, three-dimensional moving subsystem, engine, test article
with thermal control material and parameter measurement subsystem, as shown in
Fig. 15.18.
1. Vacuum Simulation Subsystem
The vacuum simulation subsystem was applied to simulate the vacuum environment
when the engine was firing on orbit.
2. 3-D Moving Subsystem
The 3-D moving subsystem was applied to fix the test article and adjust the position
of test article so that the heat flux in the plume field could satisfy the test requirement.
513
15.9 Test of Plume Effect on Thermal Control
15.9.1 Test Objective
The test objective of plume effect on thermal control was to acquire the resistant
ability to ablation and erosion of the engine plume for the thermal control material
on landing gears, bottom plate and protrusions on bottom plate during soft landing
by simulation of plume condition, and to provide important reference for thermal
design of landing gears and bottom plate of the lunar lander.
15.9.2 Test Constraints and Methodology
When the test system for plume effect on thermal control was designed, the following
constraints should be considered.
(1) It could simulate the vacuum environment while the engine was firing on orbit.
(2) It could simulate heat flow while the engine was firing on orbit.
(3) It could simulate the real thermal state
(4) It could simulate the effect of engine plume on thermal control.
Due to the limitation of vacuum test conditions, the plume of large engine was difficult
to simulate on the ground. Therefore, small engine could be applied for the equivalent
heat flow simulation. The small engine was firing in high vacuum simulation system,
while test articles covered with thermal control material was placed at appropriate
position in the plume of small engine in order to simulate the plume effect of large
engine on thermal control material.
15.9.3 Design of Test System
The test system of plume effect on thermal control was composed of vacuum
simulation subsystem, three-dimensional moving subsystem, engine, test article
with thermal control material and parameter measurement subsystem, as shown in
Fig. 15.18.
1. Vacuum Simulation Subsystem
The vacuum simulation subsystem was applied to simulate the vacuum environment
when the engine was firing on orbit.
2. 3-D Moving Subsystem
The 3-D moving subsystem was applied to fix the test article and adjust the position
of test article so that the heat flux in the plume field could satisfy the test requirement.