An official website of the United States government
Here’s how you know
Official websites use .gov
A .gov website belongs to an official government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.
A new method for heat transfer coefficient measurements of single-phase fluids during laminar flow in microchannels
Published
Author(s)
Seungwhan Baek, Ray Radebaugh, Peter Bradley
Abstract
The measurement of heat transfer coefficients in microchannels is complicated due to the small sizes involved. Moreover, a heat transfer mechanism which is not usually considered, the axial conduction effect in the channel wall, must also be evaluated in micro-scale measurements. Previous heat transfer coefficient measurements have not accounted for the axial conduction effect, and those measurements showed the inconsistent result with the theory. In this paper, a new measurement method is developed to validate the theory that predicts a Nusselt number independent of Reynolds number in the laminar flow regime for microchannels. A numerical model is used to simulate heat transfer characteristics in a microchannel with wall conduction, and to predict the wall temperature difference between a location at the end of the heater and a location 3 mm away from the heater on the microchannel. The temperature difference is experimentally measured on a 160 μm hydraulic diameter microchannel and compared with the numerical model. The comparison shows that the Nusselt number in the laminar flow regime for the microchannel is independent of Reynolds number at least down to Re=300.
Citation
International Journal of Heat and Mass Transfer
Pub Type
Journals
Keywords
Heat transfer coefficient, Microchannel, Axial conduction, Single-phase, Laminar flow
Baek, S.
, Radebaugh, R.
and Bradley, P.
(2020),
A new method for heat transfer coefficient measurements of single-phase fluids during laminar flow in microchannels, International Journal of Heat and Mass Transfer
(Accessed October 11, 2024)