Development of improved aircraft de-icing fluids

In this study the potential of utilizing poly(acrylic acid) (PAA) and polyvinylpyrrolidone (PVP) blends as improved thickening agents of aircraft de-/anti-icing fluids is investigated. Current fluid thickeners commonly comprise PAA homo or co polymers and two examples are investigated in terms of their structure, characteristics, size and the rheological profile as aqueous and solutions in a typical glycol based deicing fluid . The rheological properties of these polymer thickeners are found to be sensitive to composition, electrolyte concentration and pH as well as temperature. The rheological and aerodynamic performances of thickened water glycol mixtures were evaluated under the conditions typically experienced by de icing fluids. A model is also develop ed to simulate the rheological behaviour of the polymer solutions. The model involves consideration of reptation, relaxation of the chains by slippage or loop relaxation, and normal Rouse dynamics is appropriately adapted to reflect the structural changes of the polymer molecules and the consequent pseudoplastic behaviour. The model has helped with development of an understanding of the way in which these polymer systems create the rheological characteristics which are necessary for the action of the fluids in protecting the aircraft during the period it is at the stand and also in the initial stages of taxiing and take off. For the purpose of developing improved thickening materials with proper de icing ability and reduced gel formation tendency, various PV P PAA blends are formulated and rheologically examined together with wind tunnel testing. The gels have a tendency to form insoluble deposits which are capable of jamming the ailerons and flaps during flight. The influences of multiple mono and di valent cations, with which de icing fluids are commonly diluted was investigated. The PVP PAA blends achieve the characteristic rheological properties through a different set of interactions from those of pure PAA and are shown to be less sensitive to electrolyte effects. This study has identified a new potential de-icing fluid system

Name dc:type.qualificationname

phd

Level dc:type.qualificationlevel

doctoral-pg

Grantor dc:publisher.institution

University of Strathclyde

Year dc:date.issued

2013

Author dc:creator

• Wang, Yuchen

DOI

10.48730/447p-1r91

Identifier

T13462

OAI identifier oai:identifier

oai:strathclyde:r781wg03d