This paper presents a numerical investigation of the effects of lamination orientation on the fracture behaviour of rectangular steel wires for civil engineering applications using finite element (FE) analysis. The presence of mid-thickness across-the-width lamination changes the cup and cone fracture shape exhibited by the lamination-free wire to a V-shaped fracture with an opening at the bottom/pointed end of the V-shape at the mid-thickness across-the-width lamination location. The presence of mid-width across-the-thickness lamination changes the cup and cone fracture shape of the lamination-free wire without an opening to a cup and cone fracture shape with an opening at the lamination location. The FE fracture behaviour prediction approach adopted in this work provides an understanding of the effects of lamination orientation on the fracture behaviour of wires for civil engineering applications which cannot be understood through experimental investigations because it is impossible to machine laminations in different orientations into wire specimens.
This research presents a 3D FE method for the simulation of the variable reluctance stepper motor dynamics. The proposed model is used to obtain the optimal minimum energy control law that minimizes the energy injected by the controller. The method is based on the strong coupling of field - circuit equations and extended to eddy current, motion and nonlinearity problem. The linearization technique for the coupled problem is presented. Also the lamination of the motor core is considered. In the paper the open - loop control problem is analyzed. The proposed model is validated by the comparison with measurements. Next, to demonstrate the effectiveness of the proposed optimal minimum energy control method is applied. In both cases, the examination of the variable reluctance stepper motor dynamics and the steel loss in the core is presented and compared.
The ethylene vinyl acetate (EVA) is widely used for solar modules encapsulation. During lamination process EVA melts and chemical bonds between polymer chains are created. Its number is tightly related to cross-linking degree and it is consider as a major quality reference for module encapsulation. The lamination can be described as a process with two stages: melting and curing where the typical temperature for curing is in the range from 145 to 175°C. In the present study, for the first time, comparison of three commercial available EVA foils with low curing temperature EVA (EVA LOW). For this reason, the temperature of following lamination processes was set from a range from 115 to 175°C. The behavior of cured EVA films under investigation EVA was determined with two approaches: with extraction and with optical methods. The results indicate the applicability of these methods for the EVA cross-linking characterization. Finally, the extraordinary behavior of EVA LOW foil was noticed.