A highly sensitive gas microflowmeter

Abstract

The design of a gas microflowmeter with the following characteristics is described: the gas flowrate measurement range is ~0–3.0 mg/s; the average sensitivity in this range is 19 V/(mg s^–1); the range of recorded voltages is 25–85 V; and the error is ~2%. It is shown that when a convective heat exchange in calculations of the Reynolds and Nusselt numbers is described, the radius must serve as the characteristic size of a sphere but not its diameter.