An algebraic thixotropic elasto-visco-plastic constitutive equation describing pre-yielding solid and post-yielding liquid behaviours

Most earlier thixotropic elasto-visco-plastic models follow the quasi-static pre-yielding linear elastic assumption of Oldroyd's 1946 model. To develop a new model, present work considers more realistic non-linear visco-elastic and plastic deformation. Our model is valid for reversible (finite time scale) irreversible (infinite materials. Despite being simple algebraic equation, our appropriately explains both viscosity plateau at low shear rates diverging zero rate viscosity, using same parameters but different histories. also predicts experimentally observable transient banding due to microstructure breakage by rejuvenation steady-state aging. Furthermore, initial gel structure (waiting time) dependent stress overshoot during startup flow, hysteresis in shear-rate ramps, sudden stepdown test results, bifurcation creeping flow phenomena effectively. Depending on histories, steady state, reduces either Bingham Herschel Bulkley type with yield stress, or Newtonian fluids requires only four five thixotropic-elasto-visco-plastic (TEVP) obtainable from rheometer test. favourably series recent experimental results. The current framework has potential provide possible physical interpretation It capability predict delayed start an appropriate degradation kinetic.