Mass flow rate measurement in abrasive jets using acoustic emission

摘要: The repeatability of abrasive jet machining operations is presently limited by fluctuations in the mass flow rate due to powder compaction, stratification and humidity effects. It was found that for a typical micromachining setup could be determined using data from acoustic emission impacting flat plate. Two methods extracting were developed compared. In first method, number particle impacts per unit time direct count peaks signal. second method utilizes power spectrum density specific frequency range. Both measures correlate strongly with measured weighing samples blasted controlled periods. peak permits measurement average rate, but can only applied rates which impact approximately one order magnitude less than target plate ringing. signal processing applicable relatively fine powders at same as ringing impact. technique used monitor variations over wide range periods provides straightforward accurate means process control.