Diseño y construcción de un flujómetro, tipo obstrucción, con sensor de presión tipo FSR®

Abstract

Considering that in automation processes, instrumentation is very important and among the instrumentation, the level measurement is critical, being quite onerous level sensors, this paper aims to develop an economic flowmeter, which uses as a secondary sensor, a resistive device type FSR (Force Sensitive Resistor). For the mechanical design, was used easy to get items in a hardware store, as ½ inch Ts and plugs. In the cap, two rubber membranes holding the shaft, in which end plate with a FSR 400 Short from Interlink Electronics is located. Rubber membranes guarantee some flexibility in assembly. Conditioning electronics is performed by means of the amplification circuitry with an LM358 amplifier and data acquisition through a UNO R3 by Arduino. Variable flow line was used for determining the static characteristic, through a compressor DARI Spider 25. To determine the actual flow in the line, a Venturi flowmeter is used with a differential manometer SDE3-D10D-B-HQ4-2P-M and a flowmeter SFAB-1000U. Experimental measurement results determined that the flow has a static characteristic nonlinearity of 7.64% and a hysteresis of 7.2% for a variation of airflow from 10 to 50 GPM.