Open Access
ARTICLE
LAMINAR FLOW HEAT TRANSFER IN HELICAL OVAL-TWISTED TUBE FOR HEAT EXCHANGER APPLICATIONS
Scott Wahlquista, Amir Alia,b,*, Su-Jong Yoonc, Piyush Sabharwallc
a Idaho State University, Pocatello, Idaho, 83209, USA
b Center for Advanced Energy Studies (CAES), Idaho Falls, Idaho, 83401, USA
c Idaho National Laboratory, Idaho Falls, Idaho, 83415, USA
* Corresponding Author Email: amirali@isu.edu
Frontiers in Heat and Mass Transfer 2022, 18, 1-8. https://doi.org/10.5098/hmt.18.35
Abstract
The heat transfer performance of a novel tube configuration that combines the swirling velocity induced by oval-twisting and secondary flow generated
by a helical geometrical flow path is presented. The Nusselt number (
Nu) and friction factor (
f) are compared for the laminar flow regime (
Re = 250-
2000) under isothermal wall conditions. Under the same flow and boundary conditions, the oval-twisted helical tube increased the
Nu and slightly
increased the
f over the circular helical tube. The best performance with the highest
Nuand lowest
f occurs at the coil curvature ratio (
dh/D) of 0.17.
The quantified enhancement performance factor (h) shows a 46 - 56% increase for the oval-twisted helical tube over the circular helical tube with
dh/D = 0.17. Correlations for the
Nu and
f are developed and agreed with the numerical results: ± 6% and ± 5% for the
Nu and
f, respectively.
Keywords
Cite This Article
Wahlquist, S., Ali, A., Yoon, S., Sabharwall, P. (2022). LAMINAR FLOW HEAT TRANSFER IN HELICAL OVAL-TWISTED TUBE FOR HEAT EXCHANGER APPLICATIONS.
Frontiers in Heat and Mass Transfer, 18(1), 1–8.