Strouhal numbers for flows in deep tube array models

✍ Scribed by J.A. Fitzpatrick; I.S. Donaldson; W. McKnight

• Book ID: 104348285
• Publisher: Elsevier Science
• Year: 1988
• Tongue: English
• Weight: 913 KB
• Volume: 2
• Category: Article
• ISSN: 0889-9746
• DOI: 10.1016/s0889-9746(88)80016-1

✦ Synopsis

The analysis of the forced vibration response of tubes in heat exchanger banks is based upon the premise that the forces experienced by the tubes due to random pressure fluctuations in the first few rows of the array are significantly different from those encountered deeper in the tube bundle. The basis for this assumption is that the turbulence spectrum arising from local velocity fluctuations contains narrow band peaks in the entrance region but is broadband with no significant peaks deeper in the bank. This paper reports on an experimental study in which the frequency spectrum of turbulence has been measured in three relatively deep in-line heat exchanger tube bank models. For each array, different characteristics are observed. Strouhal numbers associated with peaks in the turbulence spectrum are shown to be identifiable at significantly greater depths than reported heretofore and their values can be functions of the measurement position and the Reynolds number of the flow. The values reported are compared with the data available from the literature for in-line square arrays using a modified Strouhal number.