Experimental and Numerical Investigation of Fluid Flow in Hydraulic Filters

Hydraulic systems are extensively used in industries. However, these systems must be free of contaminants to ensure their durability. When the contaminants entering the system are not removed with a suitable filter, sensitive parts such as pumps, motors, and actuators would be damaged. Therefore, hydraulic filters are critical elements in hydraulic systems. In this study, the flow and pressure drop in hydraulic filters were investigated experimentally and numerically. Although the main function of this device is to filter oil, it has many other functions in the system. Experiments were performed at eight Reynolds numbers in the range of 1250 ‒ 2350 at a constant viscosity. In the experiments, the pressure between the inlet and outlet of the filter was measured differently. The numerical results were used for detailed analysis of the flow after experimental verification. The analyses were performed using eight Reynolds numbers at laminar boundaries to examine the flow in the hydraulic filter. The results show that all surface areas of the filter element are not used homogeneously for fluid passage. The resultant pressure drop is due to the Dean vortex formed at the outlet of the hydraulic filter. The findings of this study can help better understand the flow recirculation regions that produce pressure drops and contaminant accumulation regions throughout a hydraulic filter from the inlet to the outlet of the flow path.