Movable Baffle Ventilation Inlet for Gas Turbine Engines
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing ventilation inlets for gas turbine engines are fixed in configuration, leading to over-purging during certain flight conditions, which increases specific fuel consumption and reduces propulsive efficiency, as they are designed to meet regulatory requirements for low power engine conditions.
Innovation Solution
A movable baffle system within the ventilation inlet conduit allows for adjustable flow control based on engine conditions, with a baffle that can be moved to increase or decrease the flow through the inlet, using actuators like shape memory alloys or piezoelectric materials to actively restrict flow during high power conditions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the ventilation inlet size is increased to provide sufficient purging at low power conditions, then the regulatory requirements for flammable vapour removal are met, but the flow excess during high power conditions increases specific fuel consumption and reduces propulsive efficiency
Solution Approach 1:
The ventilation inlet incorporates a movable baffle that can dynamically adjust the inlet area based on engine power conditions. At low power conditions, the baffle is positioned to maximize inlet area for sufficient purging. At high power conditions, the baffle moves to reduce the inlet area, optimizing fuel consumption while maintaining adequate ventilation.
Solution Approach 2:
The invention changes the geometric parameter of the ventilation inlet area dynamically. By adjusting the baffle position, the effective inlet area is varied according to engine operating conditions, allowing optimal performance across different power levels rather than being fixed for low power conditions only.
2Device complexity
If a fixed configuration ventilation inlet is used, then the device simplicity and reliability are maintained, but the ability to adapt to varying engine conditions is lost
Solution Approach 1:
The ventilation inlet transitions from a static fixed configuration to a dynamic adjustable configuration using a movable baffle. This allows the system to adapt inlet area to varying engine conditions while maintaining structural simplicity through a single moving component controlled by actuation mechanisms.
3Loss of energy
If the ventilation inlet is made adjustable to optimize flow control, then fuel consumption and propulsive efficiency are improved, but the device complexity increases
Solution Approach 1:
A movable baffle with actuation mechanism provides dynamic flow control, enabling optimization of fuel consumption and propulsive efficiency across different operating conditions. The complexity is managed through a focused mechanical adjustment system rather than complex electronic controls.
Solution Approach 2:
The invention may employ shape memory alloy actuators or piezoelectric materials to replace complex mechanical actuation systems. These materials can change shape or position the baffle through phase transitions or electric field effects, reducing mechanical complexity while maintaining flow control capability.
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 solution enables optimal flow regulation, ensuring sufficient purging of the nacelle cavity while minimizing fuel consumption and maintaining propulsive efficiency across varying engine conditions, with a fail-safe design that automatically returns to maximum flow if the actuator fails.
Implementation Method 1
The flow through such a prior art ventilation inlet is driven via the static-to-static pressure ratio between the bypass duct (in the region of the respective inlet opening) and the nacelle cavity. This pressure differential can be of the order of 1-1.6:1, dependent upon engine condition.
Implementation Method 2
using actuators like shape memory alloys or piezoelectric materials to actively restrict flow during high power conditions
Implementation Method 3
using actuators like shape memory alloys or piezoelectric materials to actively restrict flow during high power conditions
Data Source
Figure 1~2
Figure 3
Figure 4(a)~4
AI summary
A ventilation inlet including a conduit (104) arranged to convey flow from a first flow zone to a second flow zone. The conduit has a mouth region (106) presenting to the first flow zone an entrance aperture to receive the flow therefrom. The conduit has a baffle (114) spanning a portion of the conduit to define a throat region (116), the throat region being narrower than the entrance aperture. The throat region (116) is movable along the conduit (104) to control the flow through the ventilation inlet.