Thermoacoustic oscillations in cryogenics. Part 3: avoiding and damping of oscillations

✍ Scribed by H. Luck; Ch. Trepp

• Publisher: Elsevier Science
• Year: 1992
• Tongue: English
• Weight: 261 KB
• Volume: 32
• Category: Article
• ISSN: 0011-2275
• DOI: 10.1016/0011-2275(92)90279-j

✦ Synopsis

In cryogenics, geometric arrangements and operating conditions are often suitable for the excitement of thermoacoustic (or Taconis) oscillations. The basic geometry of a thermoacoustic oscillator, a half-open tube with high temperature at the closed end and low temperature at the open end, arises for example in the neck tubes of Dewar vessels or in connecting tubes between cold areas and warm pressure transducers. Oscillations may cause high heat flux into the vessel and errors in measurements. As shown in part 1 of this paper, a complete calculation of this effect is possible, but for the proper design of the piping, it is sufficient to determine the stability limit. This is demonstrated in a practical example. Very often, geometry or operating conditions cannot be selected freely, and systems capable of oscillating have to be built. For this case, or for existing systems, rules to design additional dampers are presented.