Lately, ecological and intelligent colloidal dampers based on the liquid penetration/exudation in/from lyophobic nanoporous solids were proposed. Although colloidal dampers could be attractive for various applications, they are still under research, since some unexpected findings await satisfactory explanation. For instance, colloidal dampers are able to dissipate large amounts of mechanical energy without significant heating, and such result is surprising since traditional absorbers transform almost integrally the dissipated energy into heat. In this work, using a digital infrared-camera, the temperature distribution on the external surface of a colloidal damper is recorded versus the working time and the positions of the main heat sources are identified. Such experiments allow evaluation of the temperature inside the colloidal damper's working cylinder and the absorber's generated heat. Introducing the colloidal damper inside of an incubator, variation of the hysteresis shape and dissipated energy versus the working temperature can be found. From such experimental results, ratio of the generated heat to the dissipated energy is evaluated.

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In this work, ratio of the generated heat relative to the dissipated energy, during the cyclical advancing/receding of water on surface engineered nanoporous silica is evaluated based on a thermographical method. Proposed test rig is a compression-decompression cylinder divided into two chambers, one of constant volume and the other of variable volume. Silica particles are introduced inside the cavity of fixed volume, and a micro-filter is used to separate it by the chamber of variable volume, in which only water is supplied. Using an infrared-camera, the temperature distribution on the external surface of the cylinder is recorded versus the working time, and positions of the main heat sources are identified. Such tests allow evaluation of the dissipated energy and generated heat. One finds that the surface engineered nanoporous silica is able to dissipate large amounts of mechanical energy without significant heating, i.e., maximum 17 % of the dissipated energy is emitted in the infrared frequency range. Such result is surprising since the emissions recorded from traditional frictional dissipaters, such as hydro-pneumatic absorbers, rubber and foam absorbers, etc., are mainly (about 90%) in the infrared range, and only partially in the audio and visible frequency range.

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