Research And Design Of The Micro Flow Meter

The research on crop photosynthesis and nutrient efficiency of using needs to chain flow in soil moisture measurement.This flow is usually between the small flow and micro-flow,due to the large flow range,and the instantaneous flow is extremely small,sometimes it is zero.However,the traditional flow-meter is not suitable for measuring this flow.Therefore,the design of a new type of micro-flow meter can not only solve the problem of agricultural production,but also help to expand the scope of application of existing domestic flow-meter to better meet market demand.This paper presents an active volumetric-liquid level compound flow measurement method.The servo motor was used as a power source to solve the problem that the traditional flow-meter can not work under low pressure,so the oval gear flow meter was worked by the servo motor driven.Besides,the small flow measurement was achieved through using of the oval gear flow meter.However,the Micro-flow measurement was achieved by using of the capacitive level gauge.Moreover,the cross-flow measurement was realized by the combination of liquid level gauge and oval gear flow meter.In this subject,the mechanical design of small flow-meter was completed by Auto CAD using of drawing software,which mainly includes pipeline design,capacitive level gauge design,oval gear flow-meter design and coupling design.In addition,the small flow-meter hardware circuit was designed through using of the Altium Designer drawing software,which mainly consists of the current signal is converted to voltage signal circuit,power supply circuit and display circuit.Moreover,the micro-flow meter software program and compilation was completed by the Keil 4 soft-ware,which mainly contains driver program and main program.Besides,the small flow-meter hardware circuit simulation was achieved through using of the Proteus software.Finally,the experimental system of micro-flowmeter is designed.Based on the analysis of the simulation data,it is concluded that when the height of the liquid level is greater than 50mm,the motor starts to rotate,and the flow rate is determined by the capacitive level gauge and Elliptical gear flowmeter compound measurement,and when the height of the liquid level is less than 50mm,the motor is not working,then the flow measurement is measured by the capacitive level gauge,in addition to the flow meter can achieve small flow and micro flow at the same time measuring.