2014 Volume 45 Issue 3 Pages 37-41
A pneumatic cylinder with a labyrinth seal has considerably lower friction than that with a rubber seal has, because no mechanical contact between the piston and the cylinder tube exists. However, air leakage from clearance between the piston and the cylinder tube is inevitable. This paper focuses on an investigation on leakage flow through the labyrinth seal inside a labyrinth-sealed pneumatic cylinder based on computational fluid dynamics (CFD). The CFD analysis is conducted with an ANSYS FLUENT system and, by employing a turbulence model, the leakage flow around the labyrinth seal is simulated and visualized. From the CFD analysis results, the leakage rates are found and they are compared with experimentally measured data which are acquired by means of our constructed measurement apparatus. Furthermore, we define an index to quantitatively evaluate the intensity of the turbulent flow for reducing leakage and discuss the availability of the proposed index by applying it to some CFD analysis results.
