| 摘要 |
<p>The effective flow area of a restriction in a gas flow passage, such as that of a gas turbine nozzle or vane, is determined by use of a large reservoir containing pressurized gas which is discharged through the passage in a blowdown operation in which the ratio of back pressure of the restriction to gas pressure in the reservoir is maintained below critical for sonic flow; a timer may be used to measure the time for a predetermined fall of pressure in the reservoir whilst there is sonic flow through the restriction.</p> |
