A study on the sensitivity of Drucker–Prager Cap model parameters during the decompression phase of powder compaction simulations

• Published in: Powder technology Vol. 198; no. 3; pp. 315 - 324
• Main Authors: Sinha, Tuhin, Curtis, Jennifer S., Hancock, Bruno C., Wassgren, Carl
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 25.03.2010; Elsevier
• Subjects: Applied sciences; Chemical engineering; Cohesion; Compressing; Computer simulation; Constitutive model; Drucker–Prager Cap; Elastic recovery; Exact sciences and technology; Finite element method; Finite element methods; Friction; Mathematical analysis; Mathematical models; Miscellaneous; Model calibration; Pharmaceutical; Powder; Solid-solid systems; Constitutive model; Model calibration; Pharmaceutical; Finite element methods; Drucker–Prager Cap; Powder; Cohesion; Compression; Sensitivity analysis; Compaction; Calibration; Modeling; Finite element method; Friction; Drucker-Prager Cap; Plastics
• ISSN: 0032-5910; 1873-328X
• DOI: 10.1016/j.powtec.2009.10.025

The compaction of pharmaceutical powders can be simulated using phenomenological elasto-plastic continuum models adopted from soil mechanics. These models are typically implemented in finite element codes and have been used recently to investigate the macroscopic property distributions in powders during compaction. The present study demonstrates the importance of obtaining accurate yield surface parameters for use in such models. A commercial finite element code implementing the Drucker–Prager Cap (DPC) model was used to model the compression and decompression stages of powder compaction in a tabletting operation. The parameters used in the DPC model were obtained from the literature. Although the compression stage of the process gave expected behavior, the decompression response was unrealistic for at least one set of published data. Small values for the friction and cohesion parameters resulted in a significant elastic recovery during decompression. This study demonstrates the need to obtain accurate parameter data in order to model the decompression stage of powder compaction. A commercial finite element code implementing the Drucker–Prager Cap (DPC) model with parameters obtained from the literature is used to model the compression and decompression stages of powder compaction in a tabletting operation. Although the compression stage of the process gives expected behavior, the decompression response is unrealistic for at least one set of published data. Small values for the friction and cohesion parameters result in significant elastic recovery during decompression. This study demonstrates the need to obtain accurate parameter data in order to model the decompression stage of powder compaction. [Display omitted]