Investigation of the intensification of heat transfer in a dense tube bundle washed by a longitudinal air flow

Abstract

Experiments have been performed to investigate the intensification of heating and cooling obtained by periodically grooving the tubes of a staggered bundle with S/D=1.2 washed by a longitudinal air flow in the range Re=2 · 103–105. Tubular heat exchangers with longitudinal flow through the intertube space are widely used in a number of branches of technology. To develop more compact exchangers it is necessary not only to intensify heat transfer in the intertube space by creating turbulence in various ways but also to use dense bundles of tubes (relative pitch S/D ≤1.2).