Variable Conductance Heat Pipes Mitigate Creep in Reactor Cores
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
High temperature heat pipe reactor cores face issues with creep and cascading failures due to temperature increases when a heat pipe fails, leading to hot spots and subsequent failures of adjacent heat pipes, which can be mitigated by reducing reactor core power but may cause overall temperature reduction and heat pipe shutdown.
Innovation Solution
Gas loading each heat pipe in the array to maintain adjacent heat pipes at a stable temperature by accommodating added heat loads without significant temperature changes, preventing creep and cascade failures through the use of variable conductance heat pipes and controlled gas distribution.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If reactor core power is reduced to prevent hot spots and creep, then material deformation is prevented, but overall reactor core temperature is reduced and heat pipes may stop operating
Solution Approach 1:
The patent introduces variable conductance heat pipes with gas loading, changing the thermal conductance parameter dynamically. When a heat pipe fails, the gas-loaded adjacent heat pipes can accommodate increased heat loads without significant temperature rise, maintaining stable operation without requiring overall power reduction to prevent creep.
2Temperature
If adjacent heat pipes absorb heat from failed heat pipes, then local temperature distribution is improved, but adjacent heat pipes may reach limit curves and fail in cascade
Solution Approach 1:
By loading gas into the heat pipes, the patent changes the thermal conductance parameter. Gas-loaded variable conductance heat pipes can accommodate increased heat loads from failed adjacent pipes without temperature reaching limit curves, preventing cascade failures and maintaining reliability.
Solution Approach 2:
The gas loading acts as a pre-prepared buffer that absorbs excess heat before it can cause adjacent heat pipes to reach their operational limits. This beforehand cushioning prevents the cascade failure scenario where adjacent pipes would otherwise fail sequentially.
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
The gas loading of heat pipes effectively mitigates creep and cascade failures by maintaining heat pipe temperatures within acceptable limits, preventing material deformation and subsequent heat pipe failures, ensuring continuous operation of the reactor core.
Implementation Method 1
When there is a vaporization in the hot zone, vapor and non-condensable gas is pushed to the cold end. The vapor condenses and returns to the evaporator
Implementation Method 2
The non-condensable gas stays at the cold end. With non-condensable gas staying at the cold end, the non-condensable gas creates a cold nonactive region (or zone). The non-condensable gas may block part of the condenser, preventing heat transfer to a heat exchanger.
Implementation Method 3
Each of the heat pipes in the array of heat pipes are gas loaded, mitigating or preventing creep or a cascade failure when a heat pipe in the array of heat pipes fails
Data Source
AI summary
Technique(s) to mitigate creep and/or cascade failure in high temperature heat pipe reactor cores may include gas loading each heat pipe such that when one or more heat pipes in the heat pipe array fail, the adjacent heat pipes can accommodate added heat load with little change in temperature.