Modified Splitting Distributor for Enhanced Flow Uniformity in Parallel Microchannels: An Experimental Study on the Effect of Fluid Properties

This study introduces a novel splitting distributor design to achieve a uniform gas–liquid flow distribution in parallel microchannels. The design comprises channels that sequentially reduce width by a factor of half and wedge/flow-focusing geometric modifications at the splitting junctions to facilitate efficient splitting dynamics of bubbles. The present study confirms that this configuration promotes symmetric splitting and achieves uniform flow distribution in all parallel microchannels. The effectiveness of the design is evident by low maldistribution factor (MDF) values, typically below 0.1. The uniformity is most evident in silicone oil–air systems where MDF values are below 0.06, even at high continuous phase velocities. Additionally, the study examines the impact of fluid properties (viscosity, surface tension, and density) on the uniformity of flow dynamics and pressure drops by testing five different gas–liquid systems: keeping the dispersed phase as air, the continuous phases are water+SDS solution, silicone oils (5 and 10 cSt), kerosene, and a blue dye+SDS solution. It is seen that the geometric modifications significantly enhance bubble-splitting efficiency for all gas–liquid systems. Additionally, with increasing capillary numbers (Ca) in all systems, gas bubble lengths decrease, and two-phase pressure drops escalate, highlighting the dynamic interplay of fluid properties under different flow conditions. These findings will guide future research in developing and evaluating innovative designs and modifications for various application-specific gas–liquid systems.