Liquid nitrogen in fluid dynamics: Visualization and velocimetry using frozen particles

Enrico Fonda, Katepalli R. Sreenivasan, Daniel P. Lathrop

Research output: Contribution to journalReview article

Abstract

High-Reynolds-number flows are common both in nature and industrial applications, but are difficult to attain in laboratory settings using standard test fluids such as air and water. To extend the Reynolds number range, water and air have been replaced at times by low-viscosity fluids such as pressurized air, sulfur hexafluoride, and cryogenic nitrogen gas, as well as liquid and gaseous helium. With a few exceptions, liquid nitrogen has been neglected despite the fact that it has a kinematic viscosity of about a fifth of that of water at room temperature. We explore the use of liquid nitrogen here. In particular, we study the use of frozen particles for flow visualization and velocimetry in liquid nitrogen. We create particles in situ by injecting a gaseous mixture of room-temperature nitrogen and an additional seeding gas into the flow. We present a systematic study of potential seeding gases to determine which create particles with the best fidelity and optical properties. The technique has proven capable of producing sub-micrometer sized tracers that allow particle tracking and particle image velocimetry. We review possible high-Reynolds-number experiments using this technique, and discuss the merits and challenges of using liquid nitrogen as a test fluid.

Original languageEnglish (US)
Article number085101
JournalReview of Scientific Instruments
Volume83
Issue number8
DOIs
StatePublished - Aug 1 2012

    Fingerprint

ASJC Scopus subject areas

  • Instrumentation

Cite this