D5.1 - Physical Sensors for Fluid Media in Industrial and Automotive Applications
- SENSOR+TEST Conferences 2011
2011-06-07 - 2011-06-09
- Proceedings SENSOR 2011
- D5 - Media Properties Sensors
- B. Jakoby - Johannes Kepler University Linz (Austria)
- 595 - 600
In this contribution, recent approaches and results concerning the application of sensors for physical properties of fluids are reviewed.
Physical sensors can be utilized to implement the concept of “physical chemosensors” where physical parameters are used to characterize the chemical state of a substance. This concept avoids the utilization of sensors with selective chemical interfaces, which generally feature adverse properties, e.g., in terms of ageing and poor reproducibility making them less suitable for a number of applications. Instead of directly determining the desired chemical parameter, physical parameters can serve as an indirect means to evaluate the desired information. This works particularly well if the process to be monitored is thoroughly understood (e.g., the alcohol content during a fermentation process can be related to the liquid’s mass density) or if a suitably large array of physical sensors enabling reliable correlations to the sought parameter is implemented.
Examples for physical fluid parameters are electrical and thermal conductivity, permittivity, viscosity, mass density and the speed of sound. Microsystems technology and related fabrication technologies allow the efficient realization of sensors for these parameters facilitating applications aiming at the condition monitoring of fluids, e.g., in industrial processes.
We review selected sensor principles for different applications including oil condition sensors for automotive applications.