Turbine Cooling Air Modulation via Flow Limiter Choking
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Solution Overview
Problem
Conventional turbine engine cooling systems divert significant cooling air from the compressor stage, reducing engine efficiency, as they lack effective mechanisms to modulate cooling air flow and minimize air usage during periods of reduced cooling needs.
Innovation Solution
A turbine engine cooling system incorporating a first supply feed with a flow limiter and a second supply feed with a flow control device, where the controller restricts cooling air flow through the second path, causing the first flow limiter to enforce a choked mass flow rate, thereby optimizing cooling air distribution and reducing unnecessary air diversion.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Temperature
If cooling air is diverted from the compressor stage to the turbine stage, then the turbine components are cooled adequately, but the engine efficiency decreases due to lost compression work
Solution Approach 1:
The system dynamically adjusts cooling air flow based on operating conditions. The modulated air system changes the amount of cooling air diverted from the compressor to the turbine stage, allowing the engine to optimize between cooling requirements and efficiency under different operating conditions
Solution Approach 2:
The system changes the flow parameters of cooling air by using modulated air valves and flow control devices to regulate the quantity of air diverted from different compressor stages, enabling optimization of both cooling effectiveness and engine efficiency
2Temperature
If more cooling air is diverted from the compressor stage to the turbine stage, then the turbine components are cooled more effectively, but the engine efficiency decreases further
Solution Approach 1:
The system provides dynamic control over cooling air distribution, allowing the engine to operate at optimal efficiency points under different conditions rather than using a fixed high cooling air flow rate that would continuously reduce efficiency
3Loss of energy
If the cooling system modulates cooling air flow to reduce air diversion during low cooling demand, then engine efficiency improves, but the complexity of the cooling system increases
Solution Approach 1:
The cooling system is segmented into multiple independent controllable paths with separate modulated air valves and flow control devices, allowing selective modulation of cooling air flow to different turbine stages and enabling efficiency improvement through targeted control
Solution Approach 2:
The system incorporates control mechanisms that respond to cooling demands and operating conditions, automatically adjusting the modulated air valves and flow control devices to optimize the balance between cooling effectiveness and engine efficiency
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 system effectively reduces cooling air flow to specific regions during low-demand periods, enhancing engine efficiency by minimizing air diversion from the compressor stage and ensuring adequate cooling, with a 25% reduction in total mass flow rate achieved through modulation compared to prior art.
Implementation Method 1
a flow limiter configured to choke the mass flow rate of the cooling air
Implementation Method 2
The cooling system is configured to modulate the flow of cooling air to reduce the amount of cooling air flowing to certain regions of the engine during periods in which less cooling is needed
Data Source
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AI summary
Various embodiments of the present disclosure provide a turbine engine cooling system configured to provide cooling air to a particular region of the engine to cool that region of the engine. The cooling system is configured to modulate the flow of cooling air to reduce the amount of cooling air flowing to that region of the engine during periods in which less cooling is needed. The cooling system includes a flow limiter configured to choke the mass flow rate of the cooling air provided to the region during modulation to avoid providing more cooling air than is needed to adequately cool that region of the engine.