Fluidelastic vibrations for an array of tubes. (1st Report, Flow direction and fluid density effects on the fluidelastic vibrations of a triangular array of tubes).

Water tunnel experiments were conducted on an equilateral triangular array of tubes with a pitch ratio of 1.5. Eight tests were run with different array orientations so that the effects of incident flow direction on crossflow induced vibrations could be studied. Small amplitude vorticity response was observed for all orientations except the parallel triangular array. A Strouhal number of 0.57 based on pitch velocity and independent of incident flow directions was found. The fluidelastic threshold for the normal triangular array was found to be about twice that of the parallel triangular array. However, the stability threshold for the normal triangular array was found to be quite sensitive to incident flow direction suggesting that advantage of this higher threshold should not be taken in the design of heat exchangers.

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Fluid density effects in supersonic jet-induced cratering in a granular bed on a planetary body having an atmosphere in the continuum regime

Journal of Fluid Mechanics ◽

10.1017/jfm.2021.29 ◽

2021 ◽

Vol 915 ◽

Author(s):

Kaushik Balakrishnan ◽

Josette Bellan

Keyword(s):

Supersonic Jet ◽

Fluid Density ◽

Granular Bed ◽

Planetary Body ◽

Density Effects ◽

The Continuum

Abstract

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Neighborhood Density Effects in the Recognition of Bisyllabic English Words

PsycEXTRA Dataset ◽

10.1037/e582052006-001 ◽

2006 ◽

Author(s):

Melissa K. Stamer ◽

Michael Vitevitch

Keyword(s):

Neighborhood Density ◽

Density Effects

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Analytical solution for estimating the influence of a pre-existing ground water flow on a geothermal heat production-injection well system

International Review of Applied Sciences and Engineering ◽

10.1556/irase.2.2011.1.2 ◽

2011 ◽

Vol 2 (1) ◽

pp. 13-17

Author(s):

I. David ◽

M. Visescu

Keyword(s):

Ground Water ◽

Water Flow ◽

Geothermal Energy ◽

Flow Direction ◽

Energy Resource ◽

Hot Water ◽

Injection Well ◽

Production Well ◽

Ground Water Flow ◽

The Earth

Abstract Geothermal energy source is the heat from the Earth, which ranges from the shallow ground (the upper 100 m of the Earth) to the hot water and hot rock which is a few thousand meters beneath the Earth's surface. In both cases the so-called open systems for geothermal energy resource exploitation consist of a groundwater production well to supply heat energy and an injection well to return the cooled water, from the heat pump after the thermal energy transfer, in the underground. In the paper an analytical method for a rapid estimation of the ground water flow direction effect on the coupled production well and injection well system will be proposed. The method will be illustrated with solutions and images for representative flow directions respect to the axis of the production/injection well system.

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