PREDICTION OF PRESSURE DROP FOR THE FLOW OF POLYMER MELTS THROUGH SINTERED METAL FILTERS.

Nylon, polyethylene terephthalate, and polypropylene melts were forced through sintered metal filters at typical processing temperatures, and the pressure drop was measured at several fixed flow rates. The porous sintered metal medium was modeled as a system of parallel, noncircular conduits. A power law equation fitted to data obtained with a capillary rheometer was used to account for the non-Newtonian rheological behavior of each fluid. Model predictions of the pressure drop across the sintered metal filter agreed with the observed pressure drop for all three polymer melts at the temperatures studied. The errors caused by neglecting elastic effects appear to be insignificant even for polypropylene.