Sensor Ring Circumferential Positioning for Gas Turbine Temperature Accuracy
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The even distribution of temperature sensors around a gas turbine engine's sensor ring leads to skewed average temperature readings due to uneven temperature profiles caused by fuel nozzle placement, resulting in inaccuracies of up to 150-200 degrees Fahrenheit.
Innovation Solution
The sensors are positioned offset circumferentially based on a base arc length and an offset arc length, calculated by dividing 360 degrees by the number of sensors and the number of fuel nozzles, respectively, to account for the sinusoidal temperature profile, ensuring each sensor measures a unique position on the waveform.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If sensors are disposed evenly circumferentially about the sensor ring, then the sensor arrangement is simple and easy to implement, but the determined average temperature is skewed and inaccurate due to uneven temperature profile
Solution Approach 1:
The patent applies asymmetry by positioning sensors at non-uniform circumferential intervals rather than evenly spaced positions. Each sensor is placed at a specific angular position calculated based on the sinusoidal temperature profile characteristics, creating an asymmetric sensor arrangement that accurately captures the uneven temperature distribution caused by fuel nozzle placement. This asymmetric positioning resolves the contradiction by achieving measurement accuracy through profile-matched positioning while maintaining relatively simple implementation via calculated angular positions.
2Measurement precision
If sensors are positioned to match the sinusoidal temperature profile, then measurement accuracy improves, but the sensor positioning becomes more complex and requires calculation of base arc length and offset arc length
Solution Approach 1:
The patent applies preliminary action by pre-calculating the optimal sensor positions based on the known sinusoidal temperature profile characteristics before manufacturing or assembly. The base arc length and offset arc length are determined in advance using the formula positions = (base arc length × sensor index) + (offset arc length × sensor index), allowing sensors to be positioned accurately during assembly without requiring complex real-time adjustments. This pre-planning resolves the contradiction by simplifying the actual manufacturing process while achieving high measurement accuracy.
3Measurement precision
If the number of sensors is increased to capture the temperature profile more accurately, then measurement precision improves, but device complexity and cost increase
Solution Approach 1:
The patent applies local quality by concentrating sensor positioning efforts at specific critical locations around the turbine exhaust rather than uniformly distributing sensors. The sinusoidal temperature profile has specific characteristics (peaks and troughs at known angular positions), and sensors are strategically placed at these locally important positions. This allows accurate temperature profile capture with fewer sensors by focusing measurement capability where it is most needed, resolving the contradiction between precision and complexity.
Data Source
AI summary
A method for positioning sensors about a sensor ring includes the steps of assigning each sensor in a plurality of sensors a sensor number selected from a set of sensor numbers, where the set of sensor numbers is a whole number in the range of 0 to N, and where N is the total number of sensors in said plurality of sensors minus one, disposing a first sensor at a circumferential angular position zero on the sensor ring, and disposing each sensor in the plurality of sensors at a circumferential angular position about the sensor ring, wherein the circumferential angular position is defined by an offset from a circumferential angular position zero and the offset is equal to a base arc length between sensors multiplied by the sensor number of the sensor plus a base offset arc length multiplied by the sensor number of the sensor.