Flow speed change rate sensing structure based on flexoelectric effect and measuring method thereof

Abstract

The invention provides a flow speed change rate sensing structure based on the flexoelectric effect and a measuring method thereof. The measuring structure comprises insulating layers, electrode layers and flexoelectric material layers. The multiple layers are repeatedly superposed and the spare parts are filled by insulating adhesive material. The electrode layers are externally connected with conductive wires so as to form a laminated measuring element which is connected with a charge amplifier. The output end of the charge amplifier is connected with signal processing, display and storage modules. When flow speed change rate is measured, the laminated measuring element is arranged in a flow field to be measured, liquid or gas in the flow field impacts the laminated measuring element and each layer is enabled to deform, the flexoelectric material layers deflect and deform, strain gradient is generated in deflection direction, polarized charges are generated at upper and lower surfaces and transmitted to the charge amplifier via the electrode layers, and flow speed change rate is displayed through processing. The laminated measuring element based on the flexoelectric principle is small, and low in influence on the flow field with no requirement for supplying power to the laminated measuring element, and thus the measuring structure has characteristics of being high in measuring precision without external mass blocks.

Description

technical field [0001] The invention relates to the field of measurement technology, in particular to a sensing structure and measurement method for flow rate change rate based on flexoelectric effect. 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 im...

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

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