A Coefficient to Characterize Mixing in Solar Water Storage Tanks

[+] Author and Article Information
J. H. Davidson

Mechanical Engineering Department, University of Minnesota, 111 Church Street, S.E., Minneapolis, MN 55455

D. A. Adams, J. A. Miller

Solar Energy Applications Laboratory, Colorado State University, Fort Collins, CO 80523

J. Sol. Energy Eng 116(2), 94-99 (May 01, 1994) (6 pages) doi:10.1115/1.2930504 History: Received April 23, 1993; Revised October 12, 1993; Online June 06, 2008


A dimensionless coefficient is developed to characterize the level of mixing in solar water storage tanks. The MIX number, based on the height weighted energy, or moment of energy, in the tank, ranges from 0 to 1, with 0 representing a perfectly stratified (unmixed) tank and 1 representing a fully mixed tank. Limiting values are based on theoretical determinations of the maximum and minimum values of the moment of energy in a tank without mixing and a tank with complete mixing, respectively. Use of the new MIX number is illustrated by experimental data obtained in a 372-liter storage tank operated with both a conventional drop-tube inlet and a rigid, porous stratification manifold. The initial tank temperature profile, the temperature of the water entering the tank, and test duration are varied in three testing schemes. Fluid mixing is quantified by measured vertical temperature profiles and the dimensionless MIX number.

Copyright © 1994 by The American Society of Mechanical Engineers
Your Session has timed out. Please sign back in to continue.






Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related Journal Articles
Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In