摘要 |
In order to determine the pulse repetition rate of a fluidic oscillator through which a test gas, whose density is to be determined, is flowing, the pressure pulses appearing at one outlet port of the oscillator is sensed with a pressure transducer. The pulses are integrated for a sample period such that, upon transfer or display, the accumulated count directly represents the average pulse repetition frequency during the sample. Means are provided, in a surge tank, for controlling the temperature and pressure of the test gas, and temperature and pressure transducers in communication with the sample fluid in the surge tank are each coupled to voltage-to-frequency converters which drive counters in order that the temperature and pressure of the test gas may also be displayed. An interface to a thermal printer allows the preservation of written records of prf, temperature, and pressure readings. An interface to a digital tape recorder permits magnetic recording of the data for subsequent processing.
|