Adrian Sabau

Original analytical model of the hydrodynamic loads applied on the half-bridge of a circular settling tank

The paper presents an original analytical model of the hydrodynamic loads applied on the half-bridge of a circular settling tank. The calculus domain is defined using analytical geometry and the calculus of the local dynamic pressure is based on the radius from the center of the settling tank to the current area, i.e. the relative velocity of the fluid and the depth where the current area is located, i.e. the density of the fluid. Calculus of the local drag forces uses the discrete frontal cross sectional areas of the submerged structure in contact with the fluid. In the last stage is performed the reduction of the local drag forces in the appropriate points belonging to the main beam. This class of loads is producing the flexure of the main beam in a horizontal plane and additional twisting moments along this structure. Taking into account the hydrodynamic loads, the results of the theoretical models, i.e. the analytical model and the finite element model, may have an increased accuracy.

Original computer method for the experimental data processing in photoelasticity

Optical methods in experimental mechanics are important because their results are accurate and they may be used for both full field interpretation and analysis of the local rapid variation of the stresses produced by the stress concentrators. Researchers conceived several graphical, analytical and numerical methods for the experimental data reduction. The paper presents an original computer method employed to compute the analytic functions of the isostatics, using the pattern of isoclinics of a photoelastic model or coating. The resulting software instrument may be included in hybrid models consisting of analytical, numerical and experimental studies. The computer-based integration of the results of these studies offers a higher level of understanding of the phenomena. A thorough examination of the sources of inaccuracy of this computer based numerical method was done and the conclusions were tested using the original computer code which implements the algorithm.