Journal of Non-Newtonian Fluid Mechanics, Vol.143, No.2-3, 107-119, 2007
Bread dough rheology and recoil 2. Recoil and relaxation
It is shown that a simple Lodge model with a power-law memory function and a damage function which is a function of strain can describe the behaviour of a bread dough in steady shear, steady elongation, small and medium size sinusoidal strains, and shear stress relaxation. The number of parameters needed to be found from experiment is minimal, which is a clear advantage. Some questions remain about the frequency dependence in the sinusoidal oscillatory test. We also use the model to describe the difficult, but practically important problem of recoil after steady elongation. By a simple modification of the damage function concept for the recoil phase, we are able to describe the results of experiments at elongation rates between 0.001 and 0.1 s(-1) and Hencky strains up to 2.5. Finally, although no explicit yield stress has been introduced into the model, results resemble those from models with a yield stress that depends on the rate of elongation. (C) 2007 Elsevier B.V. All rights reserved.