The use of variable coil pitch of helical tube on the hydro-thermal performance improvement

Authors

Shayan Pourhemmati, Edith Cowan UniversityFollow
Hussein A. Mohammed, Edith Cowan UniversityFollow
Abdellah Shafieian, Edith Cowan UniversityFollow

Document Type

Journal Article

Publication Title

Case Studies in Thermal Engineering

Volume

53

Publisher

Elsevier

School

School of Engineering

RAS ID

64733

Comments

Pourhemmati, S., Mohammed, H. A., & Shafieian, A. (2024). The use of variable coil pitch of helical tube on the hydro-thermal performance improvement. Case Studies in Thermal Engineering, 53, article 103944. https://doi.org/10.1016/j.csite.2023.103944

Abstract

The use of helical tubes in heat transfer appliances is desirable due to their better heat transfer characteristics, but the higher pressure drop decreases the overall performance. The variation of pitch design of a helical tube is proposed to alleviate this situation so that the pitch number does not remain constant in the total tube length. A total of six variable pitch numbers with three different diameters are proposed and investigated on the thermal and fluid characteristics. To better understand the helical tube efficiency, PEC (performance evaluation criteria) is selected as a performance indicator in the present work and simulations are performed in a laminar regime (100 ≤ Re ≤ 1600) at a constant heat flux boundary condition using computational fluid dynamics. The numerical results show that variable radial pitch has higher effects on the overall performance than variable axial pitch, and it can intensify the helical tube performance by up to 10%. The results also indicate that increasing the tube diameter leads to heat transfer and friction factor increment while increasing the Reynolds number deteriorates the overall performance.

DOI

10.1016/j.csite.2023.103944

Creative Commons License

This work is licensed under a Creative Commons Attribution 4.0 License.