A Method for Calculating the Pressure Drop in Honeycomb Dies

Three ceramic pastes based on alumina with different binder systems were characterised using physically based equations and the pressure drop measured as they passed through an experimental honeycomb die. Using an additive approach the pressure drop through the honeycomb die was predicted from the paste parameters derived by the characterisation method and the results compared with the experimentally determined pressure losses. In simple pastes based on a clay-starch binder system, where their pressure-velocity relationships were near-linear and the die entry velocity dependence was small, the predicted and experimental values were in reasonable agreement (± 10%) but in more complex systems using polymer solution binders the fit was less accurate (-10 to -45%) for the best of the four models evaluated. This was attributed to the divergent flow in the die on passage from the die holes to slots which at present cannot be modelled using the method of analysis adopted. © 1996 Elsevier Science Limited.