HYDRODYNAMIC CHARACTERIZATION OF SPLITT FRACTIONATION CELLS

The efficacy of SPLITT fractionation requires an absence of hydrodynam ic mixing between laminae constituting the thin liquid film streaming through a SPLITT cell and it requires structural elements capable of s plitting the film evenly along streamplanes. These requirements are ex amined here by both experimental tests and by a numerical analysis of flow properties near the inlet splitter. The experimental tests, invol ving dye injection and the injection of pulses of latex particles that may or may not be driven across flow laminae by gravity, show that SP LITT cell performance is close to that of ideal theory at low Reynolds numbers. The computer results verify an absence of mixing under these conditions, but when the Reynolds number and inlet flow asymmetry are both high, vortex motion is found near the inlet splitter edge, sugge stive of mixing. The conditions leading to vortex formation are define d. It is shown that tapering the splitter edge suppresses vortex forma tion.