On the hydrodynamic characterization of a passive shape memory alloy valve

A. M. Waddell, J. Punch, J. Stafford, N. Jeffers

Research output: Contribution to journalArticlepeer-review

Abstract

An attractive approach to the thermal management of next generation photonics devices (heat fluxes > 102 W/cm2) is micro-channel cooling, and micro-valves will be required for refined flow control in the supporting micro-fluidic systems. In this paper, a NiTi Shape Memory Alloy (SMA) micro-valve design for passive flow control and thermal management was prototyped at the macro scale and hydrodynamically characterized. The dynamic behavior of the valve was observed and the loss coefficient (ζν) derived from pressure-flow measurements. The hydrodynamic characterization study is important because ζν is sensitive to Re and geometry in the flow regime of the micro-fluidic system. Static replicas of the SMA valve geometry were tested for low Re (110-220) and a range of opening ratios (β) in a ø1 mm miniature channel. The loss coef ficients were found to be sensitive to flow rate and decreased rapidly with an increase in Re. A correlation was developed to interpolate ζν from a given Re and β. The valve loss coefficients obtained in this work are important parameters in the modeling and design of future microfluidic cooling systems.

Original languageEnglish
Pages (from-to)731-737
Number of pages7
JournalApplied Thermal Engineering
Volume75
DOIs
Publication statusPublished - 22 Jan 2015

Keywords

  • Forced convection
  • Loss coefficients
  • Passive valve
  • Shape memory
  • Thermal management

Fingerprint

Dive into the research topics of 'On the hydrodynamic characterization of a passive shape memory alloy valve'. Together they form a unique fingerprint.

Cite this