The aim of this paper is to model the steady-state condition of a rotary shaft\nseal (RSS) system. For this, an iterative thermal-mechanical algorithm was\ndeveloped based on incremental finite element analyzes. The behavior of the\nsealâ��s rubber material was taken into account by a large-strain viscoelastic, so\ncalled generalized Maxwell model, based on Dynamic Mechanical Thermal\nAnalyses (DMTA) and tensile measurements. The pre-loaded garter spring\nwas modelled with a bilinear material model and the shaft was assumed to be\nlinear elastic. The density, coefficient of thermal expansion and the thermal\nconductance of the materials were taken into consideration during simulation.\nThe friction between the rotary shaft seal and the shaft was simplified and\nmodelled as a constant parameter. The iterative algorithm was evaluated at\ntwo different times, right after assembly and 1 h after assembly, so that rubber\nmaterialâ��s stress relaxation effects are also incorporated. The results show\ngood correlation with the literature data, which state that the permissible\ntemperature for NBR70 (nitrile butadiene rubber) material contacting with\n~80 mm shaft diameter, rotating at 2600/min is 100�šC. The results show\n107�šC and 104�šC for the two iterations. The effect of friction induced temperature,\nchanges the width of the contact area between the seal and the shaft,\nand significantly reduces the contact pressure.
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