Sparger Nozzle Segmentation for Bubble Size and Chugging Load Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing spargers for radioactive material removal in nuclear accidents face issues with large bubble sizes and increased chugging load due to varying steam flow rates, leading to reduced radioactive material contact with cooling water and structural integrity problems.
Innovation Solution
A sparger design featuring a main pipe, header part with multiple discharge nozzles of varying lengths and configurations to maintain small bubble sizes and reduce chugging load, including a branch pipe system for diverging flow paths and alternating nozzle arrangements to enhance jet flow stability and bubble distribution.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If the sparger uses a conventional single nozzle design, then the structure is simple, but the bubbles discharged are large in size which reduces radioactive material removal efficiency
Solution Approach 1:
The single discharge nozzle is divided into multiple discharge nozzles (first discharge nozzle and second discharge nozzle) with different flow path areas. This segmentation allows the steam flow to be distributed into multiple smaller streams, creating smaller bubbles that increase the contact surface area with cooling water, thereby improving radioactive material removal efficiency while maintaining a relatively simple overall structure.
Solution Approach 2:
Different discharge nozzles are designed with different flow path areas to create local variations in flow characteristics. The first discharge nozzle has a larger flow path area while the second has a smaller flow path area, allowing each nozzle to optimize its local flow conditions for bubble generation, resulting in more effective radioactive material removal compared to a uniform single nozzle design.
2Speed
If the sparger operates at high steam flow rate, then the jet flow is strong which maintains small bubble size, but the chugging load increases and damages structural integrity
Solution Approach 1:
By dividing the steam flow into multiple discharge nozzles with different flow path areas, the concentrated high-velocity jet flow is distributed into multiple streams. This reduces the chugging load on any single nozzle while maintaining the overall jet flow strength needed to create small bubbles, thereby protecting structural integrity during high flow rate operation.
Solution Approach 2:
The flow path areas of different discharge nozzles are varied to optimize flow distribution. By changing the flow path area parameters of individual nozzles, the system can maintain effective jet flow for bubble generation while distributing the mechanical stress, reducing chugging load effects on the sparger structure during high steam flow rate conditions.
3Force
If the sparger operates at low steam flow rate, then the chugging load is reduced, but the jet flow weakens and bubble size increases reducing removal efficiency
Solution Approach 1:
Different discharge nozzles are designed with different flow path areas to optimize performance across varying flow rates. At low steam flow rates, the nozzle with the smaller flow path area can maintain adequate jet flow velocity to generate small bubbles, while the overall system experiences reduced chugging load due to the distributed flow configuration. This local optimization ensures consistent bubble quality across different operating conditions.
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 design maintains small bubble sizes, increases radioactive material contact with cooling water, reduces chugging load, and improves structural integrity by stabilizing jet flow and preventing bubble interference, thereby enhancing radioactive material removal efficiency.
Implementation Method 1
a plurality of discharge nozzles... to discharge the steam and air from the storage chamber to the storage space
Implementation Method 2
the bubbles discharged from the sparger come into contact with cooling water stored in the refueling tank, and the radioactive materials are removed while being dissolved by the cooling water
Implementation Method 3
the sparger causes a jet flow such that condensation of the discharged steam occurs outside the sparger
Data Source
AI summary
A sparger includes a main pipe connecting inside and outside of a water tank having a storage space therein for storing cooling water, so as to define a flow path through which steam and air containing radioactive materials generated outside the water tank are discharged into the cooling water, a header part connected to one end portion of the main pipe located in the storage space, and having a storage chamber in which the steam and air transferred through the main pipe are collected, and a plurality of discharge nozzles disposed in a spacing manner, each having inlet and outlet formed on one end located in the storage chamber and another end located in the storage space, respectively, to discharge the steam and air from the storage chamber to the storage space, and at least some of the plurality of discharge nozzles protruding from the header part by different lengths.