Research Papers

An Experimental Study of Heat Pipe Performance Using Binary Mixture Fluids That Exhibit Strong Concentration Marangoni Effects

[+] Author and Article Information
Kenneth M. Armijo, Van P. Carey

 Department of Mechanical Engineering, University of California at Berkeley, Berkeley 6123 Etcheverry Hall, Mailstop 5117, Berkeley, CA 94720-1740

J. Thermal Sci. Eng. Appl 3(3), 031003 (Aug 10, 2011) (7 pages) doi:10.1115/1.4004399 History: Received February 07, 2011; Revised June 09, 2011; Published August 10, 2011; Online August 10, 2011

This paper summarizes the results of an experimental investigation of the performance characteristics of a gravity/capillary driven heat pipe using water/alcohol mixtures as a working fluid. This investigation specifically explored the use of water/alcohol mixtures that exhibit strong concentration-based Marangoni effects. Experiments to determine heat pipe performance were conducted for pure water and water/alcohol solutions with increasing concentrations of alcohol. Initial tests with pure water determined the optimal working fluid charge for the heat pipe; subsequent performance tests over a wide range of heat input levels were then conducted for each working fluid at this optimum value. The results indicate that some mixtures can significantly enhance the heat transfer coefficient and heat flux capability of the heat pipe evaporator. For the best mixture tested, the maximum evaporator heat flux carried by the coolant without dryout was found to be 52% higher than the value for the same heat pipe using pure water as a coolant under comparable conditions. Peak evaporator heat flux values above 100 W/cm2 were achieved with some mixtures. Evaporator and condenser heat transfer coefficient data are presented, and the trends are examined in the context of the expected effect of the Marangoni mechanisms on heat transfer.

Copyright © 2011 by American Society of Mechanical Engineers
Your Session has timed out. Please sign back in to continue.



Grahic Jump Location
Figure 1

Photograph and schematic diagram of experimental apparatus

Grahic Jump Location
Figure 2

Heat pipe multiphase transport schematic, which comprised heat input at the evaporator section and heat extraction at the condenser

Grahic Jump Location
Figure 3

Outer evaporator surface superheat versus evaporator input heat flux for pure water with fill ratios of 35%, 45%, and 70%. The input transport heat flux is based on the heater surface area.

Grahic Jump Location
Figure 4

Finite difference analysis diagram for a three-dimensional half cylindrical channel shape factor

Grahic Jump Location
Figure 5

Experimental data and comprehensive analytical model comparison of evaporator vaporization transport heat flux for pure water with contribution due to the aluminum casing

Grahic Jump Location
Figure 6

Evaporator vaporization transport heat flux experimental data and theoretical model for pure water. The evaporator vaporization heat flux is based on the evaporator passages wetted surface area.

Grahic Jump Location
Figure 7

Heat transfer coefficient comparison between experimental data and theoretical model for evaporator heat transfer coefficient, which comprised contributions due to pool boiling nucleation and liquid water conduction

Grahic Jump Location
Figure 8

Performance experimental results for a liquid charge of 70% and for 2-propanol/water binary mixtures of 0.2 M, 0.05 M, and pure water

Grahic Jump Location
Figure 9

Binary mixture transport heat flux, for a liquid charge of 70% and for 2-propanol/water binary mixtures of 0.2 M and 0.05 M and for pure water. Critical heat flux reached in each case.



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