A study of reciprocating seals with a new mixed‐lubrication model based on inverse lubrication theory

Abstract

A mixed‐lubrication numerical model for hydraulic seals by the inverse‐hydrodynamic‐lubrication method is presented in this paper for the first time. The hydrodynamic effect on the seal inlet is taken into account as well as the asperity contact pressures. The coupling relationship between the fluid pressure, asperity contact pressure, and static contact pressure is provided by finite‐element analysis. The reverse pumping rate and friction force are calculated from the model under different fluid‐pressure and rod‐velocity conditions. All calculation results agree well with the experimental results, which are measured by the bench test as developed by the authors. By this new model, the average relative error between calculation results and experimental results is 10.5% under all test conditions, compared with 62.6% of the results by full‐film lubrication model.

Theoretical and Experimental Analysis of a Non Contacting Elastohydrodynamic Sealing

“…These simple seals reduce the leakage of a standard gap seal system to approx. 1 100 with the same initial gap height. Figure 26 shows that the working principle of the seal is not highly affected by a moving piston, provided pressure p A exceeds a minimum value of approx.…”

“…The friction force F f depends on various conditions, such as the pressure, speed, viscosity and sealing material and type. A coarse estimate of the order of magnitude is F f ≈ p d π 0.01 N/(mm.bar), which reflects, for instance, the measurements of [1]. For very small cylinder diameters in particular, e.g.…”

“…An uneven initial gap in the circumferential direction in the form of a cosine function h(ϕ) = h 0 (1+ 1 2 cos(4ϕ)) is set with the same value for h 0 = 12 µm as for the perfect case (Table 2), so h(ϕ = 0 • ) = 18 µm, h(ϕ = 45 • ) = 6 µm, h(ϕ = 90 • ) = 18 µm. The initial seal size remains the same.…”

Piston Rod Coating Material Study of Reciprocating Sealing Experiment Based on Sterling Seal

“…The friction between seals and piston rod can be measured through experiments [30]. First, we designed and built a reciprocating seal test bench.…”

Consolidation-driven wrinkling in carbon/epoxy woven fabric prepregs: An experimental and numerical study

“…The inverse hydrodynamic lubrication theory is used to solve the Reynolds equation. Since the resin pressure distribution is known, the Reynolds equation can be converted to a cubic equation, and the film thickness can be solved easily by the Newton method [46]. The details of film thickness calculation is provided in Appendix A.…”