基本信息
摘要：A thermal flowmeter is used to measure the mass flow of a medium of gas or liq. through a conductor. It consists of a metal tube carrying the medium with a heater and temp. measurement sensors. The electrical power extracted from the heater is a very accurate measure of the heat transferred to the medium. The ratio of power transferred to the increase in medium temp. is very accurately proportional to the mass fear. The heater consists of a thin film layer (3) of resistive material on an electrically insulating substrate (2) of good thermal conductivity. The substrate is thermally connected to the external surface of the metal tube (1) via an intermediate metal layer (4). Further tube sections (6,10) with thin film resistors can be used for upstream and downstream temp. measurement.
摘要附图：
