Investigation on rubber failure due to heat generation under dynamic loading

Abstract

Heat generation due to dynamic loading has been a major concern for rubber component manufacturers over many years. In engineering design and applications, current practice is to monitor the component surface temperature in accelerated durability tests. However, a number of unexpected early failures from heat generation during accelerated durability tests for rubber components have been observed even the surface temperature was well-controlled. This situation has led to the development of heat generation prediction methodology. An integrated simulation and test programme has been set up on a case investigation on a solid rubber wheel. A drum test was carried out in the laboratory. Heat conductivity, convection and radiation are included in the simulation. Important rubber heat-transfer properties were measured in the laboratory and used for the simulation. A mixed Lagrangian/Eulerian method was successfully introduced in the simulation, due to the limitations of traditional FE methods, to reduce a great amount of cost and to make the simulation possible in practice. In this case, the degrees of freedom can be reduced by three times and about 170,000 rotations saved. The temperature change in real time-domain was recorded and failure regions located. The simulation results have shown that the temperature difference between the surface and inside in the solid rubber wheel can go about four-folds. The results have been compared with the laboratory test and shown very good agreement. From this investigation, it is shown that a proper calculation is needed when a product involves a large volume of the rubber during dynamic-loading tests, and the criterion to monitor the surface temperature alone is not always reliable and could lead to a potential unexpected failure. The principles and techniques can be employed for the prediction on heat generation in industries.