| 摘要 |
<p>METHOD AND APPARATUS FOR MEASURING AND CONTROLLING FLUID FLOW RATES or the Disclosure To measure the flow rate of a fluid in a pipe, a heat pulse is injected into the fluid by a heat pulse generator, and the time of flight of the pulse between the generator and a sensor is measured. Arrival of the pulse at the sensor is determined by detecting a selected temperature level of the ascending flank of the pulse, and a predetermined temperature level of the descending flank is then detected to initiate generation of the next subsequent pulse. Since the temperature of the descending flank generally represents the temperature of the fluid between the heat pulse generator and sensor, the technique ensures that the accuracy of each successive flow rate measurement is not affected by residual heat from the preceding measurement, and yet enables measurements to be obtained at maximum frequencies. In one embodiment the measurements are used to control the flow rate of the measured fluid, and in another the flow rate of fluid in one or more additional pipes.</p> |
