A mathematical model for the transient pressure response in a capillary rheometer is implemented and validated with experimental data for both a natural rubber compound and a silicone rubber compound. The pressure decay curve after the cessation of motion of the instrument piston is shown to be consistent with the extrapolation of the power law model to shear rates two decades lower than experimentally attainable in the instrument employed. The model is useful for extending the range of the instrument in question by approximating material properties at shear rates lower than attainable in a steady flow experiment.
All Science Journal Classification (ASJC) codes
- Materials Science(all)
- Condensed Matter Physics