MAPP Lecture Series - Dr Colin Hare

We are delighted to welcome Dr Colin Hare as our next guest speaker on Thursday 19th November at 14:00.

He will give the lecture Measuring Powder Flow Under Low Stress Conditions via Blackboard Collaborate. Click here (at 1400 on 19th November) to attend.

The MAPP Lecture Series began in November 2017 with a lecture by Prof. Richard Leach, University of Nottingham. This is the 10th in the series of lectures.

Lecture abstract: Though utilised as raw materials, intermediates and products in many industries, powders frequently pose handling problems due to the challenges of ensuring reliable powder flow.

Individual particle properties such as size, shape, roughness and surface chemistry influence the ease with which they flow (flowability), the matter is made drastically more complex by the distribution of these properties present in any powder sample. As such, there is no unified theory for powder flow, so measurement of powder flowability is essential in order to be able to predict performance during processing.

A great range of devices are available for characterising powder flow, which vary in terms of mode of application, rigor and ease of use and interpretation. Whilst shear cells are established as the gold standard instrument for powder flow measurement under moderate to high stresses and quasi-static conditions, reliable measurement of powder flow under low stress conditions (1 kPa) has remained challenging. One technique that shows promise for low stress powder flow measurement is ball indentation.

This talk will give a brief summary of the above issues and key flow measurement techniques, before introducing the method of ball indentation for characterising powder flow under low stresses. The influences of bed preparation procedure, instrument operation and powder properties on the measurement and its reliability will be discussed and compared to shear cells and uniaxial compression tests.

Biography

Dr Hare is a lecturer in Chemical Engineering at the University of Surrey, specialising in particle breakage and powder flow. His research is focused on creating fundamental relationships between material properties, process conditions and product performance in powder-based manufacturing processes, utilising experimental and computational techniques. He graduated with MEng and PhD degrees in Chemical Engineering from the University of Leeds, with his thesis on Particle Breakage in Agitated Vessels. He has received funding from the International Fine Particle Research Institute (IFPRI), Corning Inc., the European Commission and the EPSRC, to research particle breakage, powder flow under low stresses and high strain rates, heat generation and transfer in powders, and powder coating. He received the Young Researcher Award at the UK Particle Technology Forum 2012, a 3rd place poster award at PARTEC 2013 and the IChemE Nicklin Medal 2015. He is the treasurer of the IChemE Particle Technology Special Interest Group (PTSIG) and was a member of the EPSRC Early Career Forum in Manufacturing Research from 2016-2020.