| 摘要 |
<p>1,138,433. Nuclear reactors. COMMISSARIAT A L'ENERGIE ATOMIQUE. 6 Feb., 1967 [22 Feb., 1966], No. 5603/67. Heading G6C. [Also in Division H4] A system for measuring the volume percentage of argon in liquid sodium nuclear reactor coolant comprises means for determining the velocity of sound in the mixture at two different static pressures. A measurement pipe 3 links the suction and delivery pipes 14, 15 of coolant pump 16 and comprises horizontal portions 1, 2 separated by valve 4 giving a fixed pressure drop between the two portions. The pressures and temperature in the portions 1, 2 are measured by means not shown, and flow rate in pipe 3 is measured by an electromagnetic device 8. The acoustic velocity in the mixture in sections 1 and 2 is determined by propagating acoustic pulses in the mixture, using electromagnetic pump 18, and timing the arrival of the pulses at piezoelectric transducers 9, 10, 11, 12, using an oscilloscope the screen of which is photographed. A given mathematical relationship establishes that, for bubbles of the size generally encountered in the coolant, acoustic velocity in the mixture is a function of both pressure and mean bubble size. The measurement of velocity at two pressures enables a non-ambiguous indication of the gas content and mean bubble size to be obtained by reference to acoustic velocity/gas content/bubble size curves derived by calibration or calculation.</p> |
