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The paper presents the findings of the research into neoprene-like soft foamed materials during compression in water. The specific features of the internal structure of such materials lead to complex deformations. This is related to the specific features of the internal structure of materials that contain a large amount of inert air. The paper also presents the findings of structural studies which explained the relationship between the elastic properties of materials and the strength of polymer bonds forming internal air cavities. When foamed the polymer sections are destroyed under compression, it results in the loss of enclosed volume of air voids. This changes the total volume and thickness of the material, which defines some physical and thermal properties of products made of such material. Hydrostatic pressure environments have their own specific features. Rheological properties of soft polymers in a hydrostatic pressure environment give rise to a composite effect of compression deformation. The study of recent developments in the research into polymer deformations in a hydrostatic pressure environment shows that it is difficult to record the stages of reversible and nonreversible compression deformation in near-real experimental simulation of diving operations. The paper presents the developments and findings of experimental design studies for a product (wetsuit) made of foamed materials that were conducted in a hydrostatic pressure environment in an enclosed volume using special Drucktank equipment by the Marine Engineering Department of the University of Rostock

To study the phenomenon of fluid-net-structure interaction of a trawl the authors investigated effects of hydro-elasticity of stiff net panels (grids) by means of special experiments in a wind tunnel. The analyses were especially focused on how the grids affect the current. One of the targets was to observe the correlation between the actual distribution of velocity distant and close to the grid and the respective hydrodynamic load distribution namely under consideration of prevailing geometrical and kinematical parameters. Another aim of the tests was to get an idea of the fluid-dynamic interactions between neighbouring mesh bars which is implicitly expressed in the well known nomographic diagram by Koritzky (1973). And last but not least the third target was to analyse the impact of the grid on the fluid parameters in correlation with further investigations regarding the understanding of the phenomenon of selectivity of fishing gears. In context of these objectives the hydrodynamic loads as well as the current distributions close to and far from the grid surface were measured by a six-component balance, by hot-wire anemometers as well as by a 2d-PIV-system. The tests were focused on small angles of attack. To control the motion of fluid two end plates and a base plate were used. The consequences of a fluid blockage at the end of a grid were analysed. Results are presented and discussed.

The article assesses two-dimensional (2D) numerical simulations of liquid sloshing in partially filled membrane-type cargo tanks of liquefied natural gas (LNG). Water and air are the fluids used in the study. Results showed a significant difference in the underlying physical mechanisms involved in the generation of high and low pressures. High pressures are linked with flows along the tank boundaries towards a sharp discontinuity in the tank geometry. Meanwhile, the low pressures are associated with overhanging structures.

To study the phenomenon of fluid-net-structure interaction of a trawl the authors investigated effects of hydro-elasticity of stiff net panels (grids) by means of special experiments in a wind tunnel. The analyses were especially focused on how the grids affect the current. One of the targets was to observe the correlation between the actual distribution of velocity distant and close to the grid and the respective hydrodynamic load distribution namely under consideration of prevailing geometrical and kinematical parameters. Another aim of the tests was to get an idea of the fluid-dynamic interactions between neighbouring mesh bars which is implicitly expressed in the well known nomographic diagram by Koritzky (1973). And last but not least the third target was to analyse the impact of the grid on the fluid parameters in correlation with further investigations regarding the understanding of the phenomenon of selectivity of fishing gears. In context of these objectives the hydrodynamic loads as well as the current distributions close to and far from the grid surface were measured by a six-component balance, by hot-wire anemometers as well as by a 2d-PIV-system. The tests were focused on small angles of attack. To control the motion of fluid two end plates and a base plate were used. The consequences of a fluid blockage at the end of a grid were analysed. Results are presented and discussed.