Gas Turbine Vane Embedded Optical Tip-Timing Probe
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional beam interrupt probes for gas turbine engines, particularly in high-pressure compressor stages, face issues with limited field of view and aerodynamic disturbances due to their design, leading to vibration and reduced measurement capabilities.
Innovation Solution
The implementation of optical tip-timing probes integrated within the airfoils of a gas turbine engine, using optical fibers housed in supports that minimize protrusion and disturbance, allowing for dual measurement capabilities without the need for invasive periscope probes.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If periscope probes are used for beam interrupt measurements, then dual measurement capability is achieved, but aerodynamic disturbance and vibration increase
Solution Approach 1:
The invention extracts the optical measurement function from the mechanical periscope probe structure and integrates it directly into the airfoil. The optical fibers are embedded within the airfoil material itself, removing the need for protruding probe structures that cause aerodynamic disturbance while retaining the dual measurement capability through strategically positioned fiber endpoints.
Solution Approach 2:
The invention merges the probe structure with the airfoil structure. The optical fibers are integrated into the airfoil's internal architecture, combining the structural component (airfoil) with the measurement component (optical probe) into a single unified element, thereby eliminating the need for separate protruding probes.
2Adaptability or versatility
If periscope probes protrude into flow passage, then field of view is improved, but exposure to hot compressed gases and aerodynamic disturbance worsen
Solution Approach 1:
The optical fibers are nested within the airfoil structure itself. The fiber endpoints are positioned at strategic locations inside the airfoil that allow the light to pass through the airfoil and intersect with rotor blades, providing the necessary field of view without the fibers protruding into the hot gas flow passage.
Solution Approach 2:
The airfoil acts as an intermediary medium that transmits the optical signal. Instead of having probes protrude directly into the hot flow, the light travels through the airfoil material itself, which serves as a protective intermediary that withstands the harsh environment while enabling optical measurement.
3Object-affected harmful factors
If periscope probes are modified to look obliquely, then protrusion is minimized, but field of view is limited and cannot be readily altered
Solution Approach 1:
The invention provides dynamic adaptability in field of view configuration. By strategically positioning multiple optical fibers at different endpoints within the airfoil structure, the system can selectively activate different fiber combinations to achieve various measurement angles and fields of view, allowing flexible adaptation without physical modification to the airfoil itself.
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 provides enhanced measurement capabilities with reduced aerodynamic disturbances and minimal modification to the engine structure, enabling effective observation and monitoring of blades with improved precision and reduced vibration.
Implementation Method 1
an optical transmitter (108) mounted in a second airfoil (66-2) aft of the target blades (72-T) and directed toward the target blades (72-T) to emit a light signal
Implementation Method 2
The transmit and receive optical fibers (102) define respective emission and reception cones (110)
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A method of observing an airflow passage within a gas turbine engine includes locating a support in view of an airflow passage and housing an optical fiber within the support.