Blade Clearance Sensor Embedded in Radial Flow Separation Wall
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current measurement devices for detecting blade tip clearance in gas turbine engines are inadequate in ensuring optimal performance due to interference with airflow and limited precision in maintaining the necessary clearance between rotor blades and the gas path.
Innovation Solution
A blade clearance sensor is embedded within a radial flow separation wall, comprising a housing and sensing element, securely attached to the splitter hoop with welds, and encapsulated in abradable coatings to minimize interference while maintaining aerodynamic smoothness, with a lead wire connecting to a measurement device for precise clearance determination.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If a blade clearance sensor is installed in the gas turbine engine to measure blade tip clearance, then measurement precision is improved, but the sensor interferes with airflow and disrupts aerodynamic integrity
Solution Approach 1:
The sensor is nested within a cavity formed in the radial flow separation wall. The cavity houses the sensor body and sensing element, allowing the sensor to be embedded rather than protruding. This nesting approach enables clearance measurement while minimizing disruption to the external aerodynamic surface and airflow patterns.
Solution Approach 2:
An abradable coating is applied to the radially inward surface of the flow separation wall surrounding the sensor cavity. This coating acts as an intermediary that erodes during operation to maintain aerodynamic smoothness and eliminate turbulence caused by the sensor embedding, thereby reducing airflow interference while preserving measurement capability.
2Object-affected harmful factors
If the sensor is embedded in the radial flow separation wall to minimize airflow interference, then aerodynamic integrity is improved, but device complexity increases due to embedding requirements
Solution Approach 1:
The flow separation wall is segmented to include a dedicated cavity for the sensor. This segmentation allows the sensor to be independently installed and removed without affecting the entire wall structure, simplifying maintenance while maintaining aerodynamic integrity through the cavity design.
Solution Approach 2:
The abradable coating is designed to be sacrificial, eroding during operation to maintain aerodynamic smoothness. This discarding of material simplifies the overall system by eliminating the need for complex active flow control mechanisms, as the coating passively adapts to maintain optimal aerodynamic conditions.
3Object-affected harmful factors
If abradable coating is applied to the flow separation wall to maintain aerodynamic smoothness, then airflow quality is improved, but manufacturing precision requirements increase
Solution Approach 1:
The abradable coating transforms the surface characteristics of the flow separation wall, changing from a rigid, precision-machined surface to a softer, erodible coating. This parameter change allows the surface to self-adjust during operation, reducing the need for extremely tight manufacturing tolerances on the underlying structure while maintaining aerodynamic quality.
Solution Approach 2:
The abradable coating is applied in advance during manufacturing, creating a buffer layer that will erode during operation to achieve the final aerodynamic profile. This preliminary action allows for less precise initial manufacturing, as the coating will self-correct surface irregularities through controlled erosion during engine operation.
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 solution allows for accurate and non-intrusive measurement of blade clearance, ensuring optimal gas turbine engine performance by embedding the sensor within the radial flow separation wall, providing precise data without disrupting airflow and maintaining aerodynamic integrity.
Implementation Method 1
a capacitive sensing element
Implementation Method 2
a radially inward surface of the splitter hoop is at least partially coated with an abradable coating
Data Source
Figure 1
Figure 2
Figure 3~4
AI summary
In combination a blade clearance sensor (100) and a radial flow separation wall (72) of a gas turbine engine (20) is provided. The blade clearance sensor (100) is embedded in the radial flow separation wall (72). The radial flow separation wall (72) comprising: a splitter hoop (74) located radially outward from blades (55) in a first flow path (FP1) of the gas turbine engine, the splitter hoop (74) being about concentric to a blade path (BP1) of the blades (55); and one or more guide vane bases (62) attached to a guide vane (60) located radially outward from the splitter hoop (74) in a second flow path (FP2), each of the one or more guide vane bases (62) being securely attached to a radially outward surface (74a) of the splitter hoop (74), wherein the blade clearance sensor (100) is configured to detect a blade clearance between the blades (55) and the splitter hoop (74).