The Prandtl micro flow sensor (PMFS): a novel silicon diaphragm capacitive sensor for flow velocity measurement

Abstract

This paper presents the setup, operation principle, and fabrication process of a novel type of flow velocity sensor. Like the well known classical Prandtl tube, it realizes flow velocity detection by measurement of the pressure difference between stagnant fluid pressure in front of the sensor and static pressure in thle flow around the sensor. This difference results in a deflection of a silicon diaphragm suspended boss, that serves as the counter electrode of an integrated capacitor which is direcfly exposed to the fluid to be measured. The main parameters influencing the sensor operation are discussed. Results of wind tunnel experiments confirm the sensor's operation principle. Finally, the sensor's merits and drawbacks are summarized.

Design and applications of MEMS flow sensors: A review

“…Through this article, we only focused on three common types of MEMS flow sensors principles namely thermal, piezoeresistive and piezoelectric devices. There are however few reports on the other types of MEMS flow sensors such as capacitive [196][197][198], ultrasonic [199,200], coriolis flow meter [201][202][203], and turbine [23,204]. Fig.…”

Sensors for Catheter Applications

“…An alternative technique is to use the obstacle to create a change in pressure. Thus a measure of the pressure before and after the obstacle will give the flow [100][101][102]. This method is more robust but care should always be taken when obstructing the blood flow.…”

Three-Dimensional Micro-Flow Measurement in a Capillary with a Diode Laser Micro-Particle Image Velocitometry

“…Chuang et al [11] developed a microscope LDA for flow measurement in a capillary, but it suffered from laser beam alignment. In addition, some other electrical sensors [12][13][14] are also presented. However, flow disturbance constrained their use.…”