Title

Heat Transfer from a Vertical Tube Bundle under Natural Circulation Conditions

Document Type

Article

Publication Date

12-1985

Publication Source

International Journal of Heat and Fluid Flow

Abstract

A rectangular loop (thermosyphon) was used to measure the average heat transfer coefficients for water at atmospheric pressure under natural circulation conditions. A twenty-one tube bundle with tubes 1.65 m long and 9.55 mm in diameter, and a pitch-to-diameter ratio of 1.33, was used as a test heat exchanger in one of the vertical legs of the loop. A natural circulation flow in the loop developed due to buoyancy differences of the fluid in its two vertical legs.

Flow visualization experiments were performed to determine the flow regimes associated with natural circulation flow longitudinal to a tube bundle. Empirical correlations for the average Nusselt number have been developed and are reported. Grid spacers arranged on tube bundles were shown to enhance heat transfer, especially for laminar flow, without any noticeable increase in pressure drop.

Inclusive pages

256-264

ISBN/ISSN

0142-727X

Comments

Permission documentation is on file.

Publisher

Elsevier

Volume

6

Issue

4

Peer Reviewed

yes