This is not the latest version of this item. The latest version can be found here.
Single-phase heat transfer regimes in forced flow conditions under exponential heat inputs
Name
Chavagnat_SPTHT_R1.docx
Description
Accepted version
Size
3.66 MB
Format
Unknown
Checksum (MD5)
04885765ea7abe45291f5dfcdd07cc10
Author(s)
Chavagnat, F
Nop, R
Dorville, N
Phillips, B
Bucci, M
Date Issued
2021
Journal
International Journal of Heat and Mass Transfer
Publisher
Elsevier BV
Citation
F. Chavagnat, R. Nop, N. Dorville, B. Phillips, M. Bucci,
Single-phase heat transfer regimes in forced flow conditions under exponential heat inputs,
International Journal of Heat and Mass Transfer,
Volume 174,
2021
Version
Author's final manuscript
Abstract
We present an experimental and theoretical investigation of single-phase heat transfer under exponential power inputs. We conduct forced flow experiments with water, covering a broad range of mass fluxes (from 0 to 19,300 kg/m2/s), bulk temperatures (from 25 to 100 °C), pressures (from 0.1 to 1.2 MPa), exponential power escalation periods (from 2.5 to 200 ms), and considering two different heater and channel geometries. We use a high-speed infrared thermometry technique to measure the space- and time-dependent heat transfer coefficient between the heated surface and the coolant, building a database covering 73 different experimental conditions. We consider turbulence as a diffusive process and develop an analytic model that can predict 80% of our database within a ±10% error, and the entire database within a ±20% error. We discuss the presence of three heat transfer regimes, i.e., transient conduction, transient turbulent diffusion, and quasi-steady turbulent heat transfer, and derive analytically the two associated transition criteria. These transitions depend on the power escalation period, fluid properties, and are connected to the profile of the turbulent diffusion properties across the boundary layer.
Terms of Use
Creative Commons Attribution-NonCommercial-NoDerivs License
Persistent DSpace Link
DOI of Published Version
10.1016/J.IJHEATMASSTRANSFER.2021.121294
