화학공학소재연구정보센터
Journal of Non-Newtonian Fluid Mechanics, Vol.129, No.2, 61-65, 2005
Model-free inversion of squeeze-flow rheometer data
A method for extracting theological data from squeeze-flow tests is proposed. The analysis, based upon the lubrication approximation for a generalized Newtonian fluid, differentiates experimental data in order to obtain an estimate of the wall shear rate (as in the Weissenberg-Rabinowitsch correction for the capillary rheometer) and of the wall shear stress. Two examples are discussed. The first is based on an approximate expression for the force required to squeeze a Herschel-Bulkley fluid. The second example concerns a power-law fluid with partial slip at the plates (but non-zero wall shear stress). Second derivatives of the experimental data are required: the interpretation of noisy results is therefore likely to be difficult. (c) 2005 Elsevier B.V. All rights reserved.