Turbine Engine Air Control Valve With Annular Minimum Flow Gap
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Traditional butterfly valves in turbine case cooling systems are optimized for new engines and completely eliminate cooling flow in the minimum flow position, leading to inefficiencies due to wear-induced radial clearance changes over time, causing the turbine case to heat up and expand beyond acceptable levels.
Innovation Solution
A turbine engine air control valve with a rotatable member featuring a vane and a floating member that forms an annular flow gap when in the minimum flow position, allowing controlled minimum fluid flow to maintain suitable radial clearance and prevent overheating.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If traditional butterfly valves are used to completely eliminate cooling flow in minimum flow position, then valve sealing performance is improved, but turbine case overheating and excessive radial clearance occur due to wear over time
Solution Approach 1:
The valve member provides different flow control characteristics at different positions: the floating seal member enables complete sealing when fully closed, while the annular flow gap provides controlled minimum flow when in minimum flow position. This local differentiation of flow control quality resolves the contradiction between complete sealing and minimum flow requirements.
Solution Approach 2:
The invention changes the flow parameter from zero (complete elimination) to a controlled minimum value through the annular flow gap. This parameter modification allows the turbine case to maintain acceptable temperature and radial clearance even after wear occurs, while still providing effective sealing when needed.
2Loss of energy
If traditional butterfly valves completely eliminate cooling flow, then energy efficiency is improved by stopping cooling, but turbine case thermal expansion exceeds acceptable limits due to component wear
Solution Approach 1:
The invention modifies the cooling air flow parameter from complete elimination to controlled minimum flow through the annular flow gap. This enables the system to maintain acceptable radial clearance dimensions even after wear occurs, while minimizing energy loss compared to continuous full-flow cooling.
3Length of moving object
If annular flow gap is provided for minimum flow, then turbine case cooling is maintained preventing excessive radial clearance, but valve structure complexity increases due to floating member addition
Solution Approach 1:
The floating seal member is designed to float freely on the valve seat surface, using fluid pressure and gravity to maintain its position and sealing function without requiring external actuation or complex mechanical support structures. This self-service mechanism reduces overall valve complexity while enabling the annular flow gap function.
Solution Approach 2:
The floating seal member serves multiple functions: it provides sealing when the valve is closed, creates the annular flow gap for minimum flow control, and maintains radial clearance control. This multi-functionality reduces the need for separate components, thereby managing structural complexity.
4Ease of manufacture
If traditional sealed valve design is used, then manufacturing simplicity is maintained, but adaptability to worn components deteriorates as radial clearance changes over time
Solution Approach 1:
The invention modifies the flow parameter from zero to controlled minimum through the annular flow gap, enabling the valve to adapt to worn components and maintain acceptable radial clearance and temperature control throughout the engine's service life.
Solution Approach 2:
The floating seal member dynamically adjusts its position based on fluid pressure and wear conditions, automatically adapting the valve's flow characteristics to match the actual radial clearance conditions in the turbine case.
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 ensures controlled cooling airflow even when the valve is in the minimum flow position, maintaining engine efficiency by preventing excessive radial clearance and heat buildup due to wear, and allows for fine-tuning of flow during assembly or retrofitting of existing systems.
Implementation Method 1
the floating member is spaced apart from the valve body to form an annular flow gap that provides a controlled amount of minimum fluid flow across the valve member as the fluid flows through the annular flow gap
Implementation Method 2
cooling air is supplied to the turbine case to control thermal expansion of the turbine case
Implementation Method 3
bypass air that is allowed to cool the turbine case
Data Source
AI summary
A turbine engine air control valve including a valve body having a fluid flow passage and a valve member disposed in the valve body. The valve member is configured to rotate about a rotation axis between a maximum flow position and a minimum flow position. The valve member includes a vane and a floating member operatively coupled to the vane. The floating member is configured to float relative to the vane, such that when the valve member is in the minimum flow position, the floating member is spaced apart from the valve body to form an annular flow gap that provides a controlled amount of minimum fluid flow across the valve member as the fluid flows through the annular flow gap.