Preventing Wall Slip in Rheology Experiments

Wall slip is a common problem when testing highly concentrated emulsions or suspensions on a rheometer. It is usually caused by large velocity gradients in a thin region adjacent to the wall. When slip occurs, the measured viscosity can be significantly lower than the actual viscosity of the sample. To overcome this influence, we have introduced a series of roughened surface geometries, such as crosshatched or serrated plates, which significantly improve the contact between the geometry and the sample to reduce slip.