Computational Fluid Dynamics Studies on the Impact of Viscosity and flow rate of Dope Solution in Hollow Fiber Ultra Filtration Membrane Formation

The performance of the polymeric membranes depends on morphology and its strength. The pressure-driven membrane separation process required good structural strength and desired flux. But these parameters depend on the formation of the right size pores, the number of pores & their distribution, and even wall thickness in surface and cross-sectional morphologies of the membrane. The desired values of the above decide the structural stability and permeate flux of hollow fibre membrane(HFM). Obtaining the desired membrane morphology yields the preferred strength and performance. In general, the characteristics of membranes derived from the flow rate of the dope solution, the shear rate, the composition of dope solutions, and the mass flux rate between solvent and non-solvent at the coagulant bath during the spinning process. So, a steady state simulation performed using the Computational Fluid Dynamics (CFD) tool to understand the fluid flow behavior inside the angular spinneret and the results correlated with the physio-structural parameters such as strength, morphology, burst pressure of the hollow fiber Ultra Filtration (UF) membrane and its formation. The study on the flow behavior of dope solution inside the spinneret carried by various the power-law index value (0.3 < n <0.7) and the dope solution flow rate (0.1< Q <1.2 mL/min). The flow profiles at the exit of 75o angular spinneret gave the delightful result of why the fiber membrane unable to withstand the high-pressure application. Also, it is exbound that the shear induced flow rate is struggle to drive some power-law index fluids and resulted in bulk flow at some spot of exit of the spinneret and leaves the hollow fiber membrane to form uneven wall thickness. The dope flow rate and the power-law index values need to be optimized to understand the formation of UF membrane morphology.