Flexoelectric effect-based three-dimensional flow rate-of-change sensor and measuring method

Abstract

The invention provides a flexoelectric effect-based three-dimensional flow rate-of-change sensor and a measuring method. The sensor comprises an L-shaped three-dimensional body element and a ball-shaped insulating material. The L-shaped three-dimensional body element comprises an insulating layer, an electrode layer and a flexoelectric material layer, wherein the layers are stacked up and the empty part of the L-shaped three-dimensional body element is filled with an insulating adhesive material. The electrode layer is connected with a charge amplifier. The output end of the charge amplifier is connected with a signal processing, display and storage module. During the measurement of the flow change rate, the fluid in a three-dimensional flow field impacts with the ball-shaped insulating material, so that the layers of the L-shaped three-dimensional body element are deformed. The flexoelectric material layer is provided with a strain gradient along the deflection direction thereof to generate four groups of polarization charges. The polarization charges are transferred to the charge amplifier via the electrode layer and then are processed, so that the three-dimensional flow rate of change can be displayed in real time. The sensor has the advantages of small size, little influence on the flow field, no power supply for the flexoelectric material layer, no extra mass block, wide measuring range, good real-time performance, direct measurement, high precision, simple structure and the like.

Description

technical field [0001] The invention relates to the technical field of sensors, in particular to a flexoelectric effect-based three-dimensional flow velocity change rate sensor and a measurement method. Background technique [0002] Most of the existing flow and velocity measurement technologies use electromagnetic measurement technology and laser measurement technology. In addition to flow velocity measurement, the real-time monitoring of flow velocity change rate also has important applications in military and daily life. For example, when the aircraft skin is in flight, the incoming flow velocity changes, the force on the skin changes, and the flight of the aircraft is affected. ; When the oil is transported through the oil pipeline, the flow rate of the oil changes, the impact force of the oil on the pipeline is different, and the damage caused to the pipeline is different; when the car is running at high speed, the change rate of the crosswind wind speed has a serious i...

AI Technical Summary

Problems solved by technology

However, the piezoelectric acceleration sensor needs to place a mass block on the piezoelectric crystal, and in order to isolate any strain of the test piece from being transmitted to the piezoelectric element, it is generally necessary to thicken the base or use a material with higher rigidity to make it. The weight of the body and the base accounts for almost half of the weight of the sensor, and the weight of the actual effective parts is small, and the piezoelectric material is a heavy metal-containing material, and its material itself is a potential threat to the environment

Images