2.3  Preparation

The experiment described in this paper was performed with paraffin (melting point range between 56o and 58oC) mixed with a small fraction of 800-grit silicon carbide particles. Silicon carbide grains act as marker particles for flow analysis. Sixty-two milligrams of paraffin (56oC-58oC) with random distributed silicon particles were pressed in a hand-driven pneumatic press for 20 sec at 50 bar and then manually insert between two glass slides with frosted grips. Both glass slides were coated with thin film of a liquid soap to reduce the friction between paraffin and glass slides.