| 摘要 |
A dilution technique for measuring the flow rate of a fluid stream includes injecting a tracer gas into a gas stream and then introducing the resulting tracer stock gas stream at a constant flow rate into the fluid stream. The concentration of tracer stock gas in a fluid stream sample is then obtained. A sample of the tracer stock gas stream is obtained at a point before this stream is introduced into the fluid stream. The resulting tracer stock gas stream sample is injected at a flow rate which can be varied, for example, by a peristaltic pump, into the gas stream. The concentration of a sample from the resulting tracer stock gas sample-in-gas stream sample is measured. By varying the flow rate of the tracer stock gas stream sample the two measured concentrations can be equalised. When the concentrations are equal, a relationship exists between the flow rates of the fluid stream, the tracer stock gas stream and the tracer stock gas stream sample. Since the latter two flow rates are known, the flow rate of the fluid stream can be determined. |
