Flow of Pastes in Bent Tubes

摘要

Processing requires that pastes flow in piping net- works often into dies or moulds. Here paste flows in bent tubes of constant radius of curvature but vary- ing angles have been investigated using a modified ram extruder. Measurements for two model pastes have shown that the pressure drop for bends below 105° is linearly dependent on the angle of bend, but at larger angles this relationship does not follow. Theoretical predictions from plasticity theory con- Sistently underestimate pressure drops although the General form and magnitude is correct. The mecha- Nisms controlling the flow, especially for larger Angles, need to be investigated.