Aircraft Air Temperature Sensor Bushing Thermal Isolation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Turbine engine total air temperature sensors face challenges due to adverse conditions such as high Mach numbers and icing, which can affect reading accuracy and durability, particularly in aircraft applications where precise temperature measurements are critical for propulsion and power generation.
Innovation Solution
An air temperature sensor design featuring a housing with a support tube and element shroud, along with a bushing that thermally isolates and centers the temperature sensor, providing mechanical support and maintaining accuracy across a wide temperature range by isolating the sensor from heated components.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If the temperature sensor is exposed to the air flow stream for accurate temperature measurement, then measurement precision is improved, but the sensor is affected by adverse conditions (high Mach numbers, icing, water, debris) which worsens reliability
Solution Approach 1:
The sensor assembly is divided into functional segments: the housing that interfaces with the air stream, the support tube that provides structural support, the element shroud that protects the sensor element, and the bushing that provides thermal isolation. This segmentation allows each component to perform its specific function while protecting the sensor element from adverse conditions.
Solution Approach 2:
The bushing acts as an intermediary component between the housing and the temperature sensor assembly. It provides thermal isolation while allowing the sensor to accurately measure air temperature by blocking heat transfer from the housing to the sensor element, thus protecting the sensor from thermal effects while maintaining measurement accuracy.
2Device complexity
If the sensor housing is in direct contact with the temperature sensor for structural support, then device complexity is reduced, but thermal isolation is compromised which worsens measurement accuracy
Solution Approach 1:
The bushing serves as a thermal intermediary that blocks heat transfer between the housing and the temperature sensor assembly. This simple component effectively isolates the sensor element from thermal effects of the housing without adding significant complexity to the overall structure.
Solution Approach 2:
The temperature sensor is nested within the support tube, which is in turn nested within the element shroud, which is nested within the housing. This nested arrangement provides multiple layers of protection and support while the bushing provides thermal isolation at the interface between the housing and the nested assembly.
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 ensures improved sensor performance and accuracy by maintaining consistent temperature readings from -73 to 260 degrees Celsius, enhancing durability and reliability in harsh conditions.
Implementation Method 1
a bushing isolating the trailing edge of the housing from the distal end of temperature sensor
Data Source
AI summary
An air temperature sensor for use on an aircraft can include a housing defining an interior and having a trailing edge, a temperature sensor having a distal end and located within the interior, a support tube surrounding at least a portion the temperature sensor, an element shroud surrounding at least a portion of support tube, and a bushing isolating the trailing edge of the housing from the distal end of temperature sensor.