Paper Info
Title
Viscous Heating Assists Jet Formation During Needle-free Jet Injection of Viscous Drugs.
Abstract
<italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Objective:</italic> Jet injectors use a high-pressure liquid jet to pierce the skin and deliver drug into underlying tissues. This jet is formed through a short, narrow orifice; the geometry of the orifice and the properties of the fluid affect the nature of the flow. We aimed to discover information about the turbulent and viscous processes that contribute to pressure loss and flow patterns during jet injection. <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Methods:</italic> We used computational fluid dynamics methods and experimental observation to investigate the effects of nozzle geometry, fluid viscosity, and viscous heating on jet production. We experimentally verified the temperature change of the jet during ejection, using an infrared camera. <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Results:</italic> Our models accurately predict the average jet speed produced for two example nozzle geometries over two orders of magnitude of viscosity. The models reveal the previously unreported importance of viscous heating in the formation of the jet. Temperatures >65 °C were predicted at the edge of the flow as a result of viscous heating. These caused a significant local reduction in viscosity and effectively allowed the fluid to lubricate itself. Our experiments confirmed changes in mean jet temperature of up to 2.5 °C, which are similar to those predicted by our model (∼2.8 °C). <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Conclusion:</italic> These results reveal the importance of the viscous heating properties of a fluid in the formation of high-speed jets for drug delivery. <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Significance:</italic> This property is crucial to consider when formulating new drugs for needle-free jet injection <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">.</italic>
Year
DOI
Venue
2019
10.1109/TBME.2019.2906356
IEEE transactions on bio-medical engineering
Keywords
Field
DocType
Orifices,Drugs,Geometry,Viscosity,Fuels,Heating systems
Lubrication,Computer science,Pressure drop,Turbulence,Jet (fluid),Body orifice,Electronic engineering,Viscosity,Mechanics,Computational fluid dynamics,Nozzle
Journal
Volume
Issue
ISSN
66
12
0018-9294
Citations 
PageRank 
References 
0
0.34
0
Authors
5
Name
Order
Citations
PageRank
Rhys M. J. Williams122.17
James W. Mckeage202.03
Bryan P. Ruddy335.04
Poul Nielsen4105.26
Andrew J. Taberner52810.59