Stud Bolt Cooling via Venturi Air Path
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Nuclear reactors face thermal deformation and structural vibration issues due to high temperatures in the substructure of steam generators, leading to equipment wear and potential leaks, which existing solutions cannot address effectively during normal operation or before steam generator replacement.
Innovation Solution
An apparatus with stud bolts featuring venturi-type axial through holes and inclined vent holes, along with a skirt flange vent passage and air-passing grooves, forms an air circulation/cooling path to reduce the temperature of the dead air region, preventing thermal deformation and improving stability without large-scale equipment replacement.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Temperature
If conventional solid stud bolt structure is used, then structural strength is maintained, but thermal deformation and heat fatigue occur due to high temperature in dead air region
Solution Approach 1:
The solid stud bolt is segmented into multiple parts by introducing axial through holes and inclined vent holes, allowing air circulation while maintaining structural integrity through strategic hole placement and dimensions
Solution Approach 2:
Air flow is introduced through the axial through hole and inclined vent holes to create a cooling path, using pneumatic principles to remove heat from the dead air region and cool the stud bolt and sliding base
2Temperature
If air circulation path is introduced through stud bolts, then cooling effect is achieved, but structural strength may be compromised
Solution Approach 1:
The cooling function is localized to specific regions through axial through holes and inclined vent holes, while the bulk material retains its load-bearing capacity, creating local thermal management without compromising overall structural strength
Solution Approach 2:
The stud bolt becomes a composite structure combining solid material for strength with hollow channels for cooling, effectively integrating thermal management functionality into the load-bearing component
3Reliability
If conventional solid structure is used, then manufacturing is simple, but thermal deformation causes operational instability
Solution Approach 1:
The cooling function is merged with the structural stud bolt by integrating axial through holes and inclined vent holes directly into the bolt design, eliminating the need for separate cooling systems and reducing overall device complexity while improving reliability
4Temperature
If high temperature heat is transmitted to sliding base, then thermal deformation occurs, but adding cooling structures increases device complexity
Solution Approach 1:
The stud bolt serves multiple functions simultaneously: structural support, heat transfer, and air circulation cooling. The axial through hole and inclined vent holes enable the stud bolt to function as both a structural element and a cooling conduit, reducing the need for additional dedicated cooling components
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 apparatus effectively reduces the temperature of the dead air region by 40% compared to conventional systems, preventing heat fatigue and thermal deformation of stud bolts and sliding bases, thereby enhancing the operational stability of nuclear reactors.
Implementation Method 1
the axial through hole having a venturi-type neck part whose internal flow passage has a reduced diameter, so that air flowing through a flow passage of the neck part increases in a flow rate and decreases in pressure
Implementation Method 2
an air circulation/cooling path is formed between a dead air region in the substructure and surroundings through the axial through hole via the inclined vent holes, the air-passing grooves, and the vent passage, thereby cooling the stud bolt and the sliding base
Implementation Method 3
air flowing through a flow passage of the neck part increases in a flow rate and decreases in pressure
Data Source
AI summary
An apparatus for cooling a substructure of a steam generator in a nuclear reactor is provided. The apparatus includes a plurality of stud bolts (110) fastening a skirt of the steam generator to a sliding base. Each stud bolt is provided at the center thereof with an axial through hole (112), a flange of the skirt is provided on one side thereof with a vent passage (122), and each stud bolt is provided with at least one vent hole (114) communicating with the axial through hole (112), thereby forming an air circulation/cooling path between the vent passage (122) and the axial through hole (112) via the vent hole (114).