Capacitive Pressure Transducer Thermal Stability
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing pressure transducers face inaccuracies due to the thermal transpiration effect when ambient temperatures differ from the controlled temperature, requiring corrections that complicate measurements and reduce reliability.
Innovation Solution
A high accuracy capacitive pressure transducer is integrated into a temperature-controlled box with a temperature control unit, ensuring the pressure sensor operates at ambient temperature, eliminating the need for thermal corrections by maintaining ±2 mK stability within the 15°C-30°C range.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If the pressure transducer operates at a controlled temperature different from ambient temperature, then measurement accuracy is improved, but thermal transpiration effects introduce errors and require complex correction procedures
Solution Approach 1:
A thermal isolation interface is introduced between the pressure transducer and the temperature control box. This interface comprises a first portion attached to the transducer and a second portion attached to the box, creating a thermal barrier that isolates the sensor from external temperature fluctuations while allowing controlled temperature management when needed
Solution Approach 2:
The pressure transducer is extracted from direct exposure to ambient temperature variations by placing it inside a dedicated temperature control box. The sensor is thermally isolated from the external environment, allowing it to operate at a stable controlled temperature independent of ambient conditions
2Stability of the object's composition
If the pressure sensor is thermally isolated from ambient temperature, then temperature stability is improved, but thermal transpiration effects occur when temperature differences exist
Solution Approach 1:
A thermal isolation interface acts as an intermediary between the pressure sensor and the temperature control box. This interface allows the sensor to be thermally coupled to the controlled environment while preventing direct thermal pathways that would cause thermal transpiration effects
Solution Approach 2:
The thermal isolation interface creates different thermal zones: the pressure sensor operates in a locally controlled temperature environment while the external environment can vary. This local temperature control ensures stability without causing thermal gradients across the measurement system
3Stability of the object's composition
If electronic circuits are used for temperature control, then temperature stability is improved, but heat dissipation from circuits raises sensor temperature above ambient
Solution Approach 1:
The thermal isolation interface serves as a thermal mediator that separates the heat-generating electronic circuits from the pressure sensor. It allows the sensor to operate at a temperature close to ambient while the electronic circuits can dissipate heat without directly heating the sensor
Solution Approach 2:
The system is segmented into distinct thermal zones: the pressure sensor operates in a temperature-controlled zone with minimal heat input, while electronic circuits operate in a separate zone where heat dissipation is isolated. The thermal isolation interface maintains this segmentation
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 stable and accurate pressure measurements without thermal transpiration effects, enhancing reliability and simplifying the measurement process by maintaining the pressure sensor's temperature in sync with ambient conditions.
Implementation Method 1
the pressure may be measured differently due to the thermal transpiration effect
Implementation Method 2
thermoelectric modules (10) disposed under the heat receptor (8) and between the heat insulators (11)
Data Source
Figure 1
Figure 2~3
Figure 4
AI summary
The invention relates to a high accuracy capacitive pressure transducer with improved thermal properties capable of performing measurements at a fixed temperature, with stability better than ± 2mK, in the temperature range of 15°C- 30°C-, and which does not require the use of correction for thermal transpiration effect.