|Measurement of Friction Coefficient on a Powder Layer and Fluid Dynamic Study|
We used cake flour in the experiments. The following image is a magnified image of flour.
A bulk density of the flour used is 0.5×103kg/m3 when sieved and 0.7×103kg/m3 when compressed.
Appendix Fig. 1. A magnified image of flour used in experiments. Click image for an enlarged view.