A microcomputer-based averaging flowmeter using FORTH programming language

A flowmeter was designed and constructed to measure the average fluid flow over a ten-minute interval. The instrument used a bubbler system and differential pressure sensors to measure the density-compensated level in a sealed vessel. A microcomputer was used to record a fluid-level histogram and to calculate the slope of the histogram through a linear least-squares regression. The average flow is proportional to the slope of the level histogram. The instrument met or exceeded all requirements.