Turbulent drag reduction by polymer additives: Fundamentals and recent advances

TL;DR

This review summarizes fundamental principles and recent advances in the use of polymer additives for turbulent drag reduction, highlighting new insights, ongoing debates, and future research directions.

Contribution

It provides a comprehensive overview of classical theories and recent developments, bridging foundational knowledge with cutting-edge research in polymer-induced drag reduction.

Findings

Polymer additives significantly reduce turbulent flow energy dissipation.

Recent research offers new insights into long-standing problems.

Open questions and debates remain in the field.

Abstract

A small amount of polymer additives can cause substantial reduction in the energy dissipation and friction loss of turbulent flow. The problem of polymer-induced drag reduction has attracted continuous attention over the seven decades since its discovery. However, changes in research paradigm and perspectives have triggered a wave of new advancements in the past decade. This review attempts to bring researchers of all levels, from beginners to experts, to the forefront of this area. It starts with a comprehensive coverage of fundamental knowledge and classical findings and theories. It then highlights several recent developments that bring fresh insights into long-standing problems. Open questions and ongoing debates are also discussed.