Helical groove seals are non-contacting annular seals used in pumps and other rotating machinery to reduce the flow of working fluid across a pressure differential. These seals have continuously cut grooves, like the threads of a screw, across the surface of the rotor, the stator, or both surfaces. They function to reduce the flow of working fluid by two physical mechanisms. First, fluid traveling in the axial direction dissipates kinetic energy as it expands in the grooves and then is forced to contract in the jet stream region between the grooves. Second, the fluid within the grooves is displaced toward the high pressure region through the pumping action of the helical grooves. In multistage pump design, it is now common to use helical groove seals with grooves on both the surface of the rotor and stator where the grooves are opposing in direction. That is, the case where the grooves on the rotor pump towards the outlet, but the grooves on the stator pump towards the inlet. Despite this being the industry standard, no data in the literature exist that suggests that this design is better than other possible double surface helical groove seal configurations. This work examines the conditions in which each configuration of double surface helical groove seals is preferable. To accomplish this, simulations are run using ANSYS CFX for a variety of operating conditions for each configuration. The operating conditions varied are pressure differential and rotor speed. The baseline design of this data is a validated against experimental results from the literature showing the performance of opposing groove direction helical groove seals. This paper also discusses the validity of the multi-reference frame steady-state setup that can be used to efficiently simulate these seals. Finally, this study presents discussion and conclusions of the preference to opposing direction helical groove seals based on the flow mechanisms of the seal configurations. This work will form the basis of future work designing computationally efficient analysis tools to analyze these double surface helical groove seals, which are already widely used but lack computational analysis tools.

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