Thruster Thermal Insulation Using Ti Alloy Columns
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Monopropellant catalytic thrusters face challenges with heat transfer from the catalyst layer to the propellant valve and spacecraft, leading to high power consumption and potential temperature-related failures due to the limited thermal insulation capabilities of cobalt-nickel alloys used in these systems.
Innovation Solution
The thruster design incorporates a Ni alloy chamber and propellant introduction member for the catalyst layer, with a Ti alloy propellant valve flange supported by columns, minimizing heat conduction to the propellant valve and reducing thermal insulation demands.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Temperature
If a cobalt-nickel alloy chamber is used to hold the catalyst layer, then the chamber can withstand high temperatures, but the thermal insulation capability is insufficient leading to excessive heat transfer to the propellant valve
Solution Approach 1:
A thermal insulation layer made of low thermal conductivity material is introduced as an intermediary between the high-temperature catalyst layer chamber and the propellant valve. This intermediary layer blocks heat transfer while allowing the chamber to maintain high temperature for catalyst operation, thereby solving the contradiction between withstanding high temperature and preventing heat loss.
2Loss of energy
If thermal insulation structures are added between the chamber and propellant valve, then heat transfer is reduced, but the device complexity increases
Solution Approach 1:
Instead of providing thermal insulation throughout the entire chamber structure, the insulation layer is applied locally only at the portion of the chamber wall that contacts or is near the propellant valve. This localized approach reduces heat transfer to the valve while minimizing the addition of structural complexity.
3Reliability
If the propellant valve is kept at low temperature, then the propellant valve safety is improved, but the power consumption of the heater increases
Solution Approach 1:
A thermal insulation layer is positioned between the high-temperature catalyst chamber and the propellant valve to act as a heat barrier. This intermediary reduces the heat load on the valve, allowing it to remain at safe low temperatures without requiring excessive heating power, thus resolving the contradiction between valve safety and energy consumption.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This design effectively reduces heat transfer to the propellant valve, lowering power consumption and preventing temperature-related failures, while maintaining the catalyst layer at high temperatures necessary for efficient operation.
Implementation Method 1
a propellant valve flange of a Ti alloy with a plurality of columns of a Ti alloy is arranged between the chamber and the propellant valve to support the chamber by the columns
Implementation Method 2
supply a propellant such as hydrazine from a tank to a catalyst layer via a propellant valve and an injector to cause the propellant to decompose on the catalyst layer
Implementation Method 3
a heater is provided to preheat the catalyst layer and keep the propellant valve at appropriate temperature
Data Source
Figure 1
Figure 2A
Figure 2B
AI summary
Of the constituting parts of a support structure (20) for a chamber (8) holding a catalyst layer which can reach high temperature, a chamber flange (24), fasteners (36a, 36b, 36c), an introduction pipe (6) conveying hydrazine and an introduction pipe flange (26) are made of a Co-Ni alloy resistant to high temperature, and a propellant valve flange (22) and columns (30a, 30b, 30c) arranged between the chamber and a propellant valve (4) which needs to be kept at low temperature as compared with the catalyst layer are made of a Ti alloy having a high thermal insulating capability.