RECENT APPLICATIONS OF THE GREENSPAN AND TSCHIEGG DATA ON NEUTRON INDUCED CAVITATION THRESHOLDS

West, Colin D

Oak Ridge National Laboratory

关键词: Heating;    Protons;    Reflection;    Nucleation;    Proton Beams;   

DOI  :  10.2172/932615
RP-ID  :  ORNL/TM-2007/025
RP-ID  :  DE-AC05-00OR22725
RP-ID  :  932615

美国|英语

来源: UNT Digital Library

【 摘 要 】

In 1967 Greenspan and Tschiegg published a paper on radiation induced acoustic cavitation. They researched the thresholds for cavitation induced in various liquids by fast neutrons, {alpha}-decay recoils and fission fragments. It turns out that these data can be used to verify predictions of a more recent theory of radiation induced cavitation nucleation. In 1979, in a report to their sponsor (The Office of Naval Research) they published new details of their results on neutron induced cavitation thresholds, including tables of the thresholds at different temperatures for various liquids. They were also some fission fragment results, but none of the {alpha}-decay recoil data. By that time Greenspan had evidently retired while I had left the field of cavitation research and did not know of the existence of their report [which also contains the only published record of some cavitation threshold measurements made by West and Howlett at Harwell, England]. Later still, in 1982, Greenspan and Tschiegg published the graphical data--but not the tables--in a more easily accessible form. In the late 1990s I revisited the problem of calculating radiation induced cavitation thresholds. There was interest in this because the Spallation Neutron Source (SNS) project, then just beginning, planned to use a liquid mercury target to produce intense bursts of neutrons when irradiated by a pulsed, high energy proton beam. It was known that the pressure waves produced by local heating when the proton pulse struck the target could, upon reflection at the walls of the mercury container, give rise to very high, although brief, negative pressure waves in the mercury. There was concern that cavitation might result and, if it did, might lead to undesirable effects. With the encouragement of the SNS target team this author managed further to develop an earlier method of calculating the threshold for such cavitation, and the SNS project kindly provided funding to publish the work in two ORNL reports. Around that period, I was also able to acquire a copy of Greenspan and Tschiegg's 1979 report to which, fortunately, they had referred in their 1982 Acoustical Society of America note. Now retirement has given me opportunities to return to some work in the field of cavitation and to study some topics for my own interest--such as this one. And it is a pleasure to acknowledge that the Greenspan and Tschiegg publications still contain data, hitherto unused, that can bring new light to cavitation studies.