| 摘要 |
<p>1300159 Ultrasonic temperature measuremerit COMMISSARIAT A L'ENERGIE ATOMIQUE 4 Aug 1970 [18 Aug 1969] 37573/70 Heading H4D Signals from piezo-electric transducer are coupled to a waveguide and impringe on a mirror which focuses them on to a reflector, the end of the waveguide, mirror and reflector being immersed in a fluid, and reflections are passed back via the transducer and a changeover switch to a receiver wherein deviations in the echo transit time indicate changes in temperature of the fluid. A probe for measuring the temperature of liquid sodium coolant 5 in a reactor comprises a stainless steel rod passing through the seal plug 6 and fixed to the core casing 12 and which is terminated in a cylinder 8 which directs acoustic energy from transducer 1 on to reflector 9 via mirror 7. Due to the difference in acoustic impedance between the rod 2 and liquid 5, multiple reflections occur. The transit time of n echoes is found by counting clock pulses passed by a gate which is opened by the first received pulse and closed by the nth (detected by a preset counter). The clock pulse counter output is read out to memory and display devices and an alarm is actuated if the temperature deviation is excessive. To avoid turbulence across the measuring path, a wedge deflector is provided at the base of an opentopped duct 14 to provide steady flow.</p> |
