Papers by Keyword: Elliptical Hole

Abstract: In the structure of passenger vehicles there are components that absorb the impact load, which components are commonly thin-walled square tube. The design of the impact energy absorber model can be carry-out by experiment, simulation, and analysis. In the design of this impact energy absorbing component, an elliptical hole was used as a crush initiator to reduce peak loads and set the start of the bending pattern. Analytical predictions were made to reduce costs and speed up time to obtain mean load and peak loads values from the same shape model. In this study, a thin-walled square tubes model is used with an elliptical hole that have ratio of horizontal axis and vertical axis is from 3:7 until 7:3. The result of this study showed that the prediction of the peak load and average load by analytical means has a good conformity with the simulation. Keywords: Impact energy absorber, analytical, square tube, elliptical hole.

Abstract: Using the complex variable function method and the technique of conformal mapping, the fracture mechanics of two symmetric collinear cracks originating from an elliptical hole in a one-dimensional (1D) hexagonal piezoelectric quasicrystals (QCs) are investigated under anti-plane shear loading and electric loading. The crack is assumed to be either electrical impermeable or permeable. The exact solutions in closed-form of the stress intensity factors (SIFs) of the phonon field and the phason field, and the electric displacement intensity factors (EDIFs) are obtained. In the limiting cases, the new results such as Griffith crack, a circular hole with equal two edge cracks and cross crack can be obtained from the present solutions. In the absence of the phason field, the obtainable results in this paper match with the classical results.

Abstract: Experimental, analytical and finite element techniques are commonly known methods used in determining highly localized stress occurring in the body under loading as a result of geometric discontinuities. In this study, we use NURBS-based isogeometric analysis (IGA) to investigate the stress concentration factor (SCF) on three-dimensional geometry with discontinuity feature. The results show that IGA technique is in good agreement with analytical values, thus providing a more effective realistic way of determining SCF.

Abstract: The analysis on a two-dimensional infinite anisotropic magnetoelectroelastic solid containing an elliptic hole subjected to a generalized force on the hole surface is performed in this paper. By employing the Stroh formalism, the method of analytical continuation, the technique of conformal mapping, the concept of superposition and the exact electromagnetic boundary conditions, the Green’s functions are obtained.

Abstract: Highly birefringent extruded elliptical-hole photonic crystal fibers (PCFs) with single defect and double defect are proposed and investigated, which are supposed to be achieved by extruding conventional triangular-lattice circular-hole PCFs. Comparative research on the birefringence and the confinement loss of the proposed PCFs with single defect and double defect is presented. Simulated results show that the proposed extruded elliptical-hole PCFs with single defect and double defect can be with high birefringence up to the order of 10-2. Confinement loss increases when the ellipticity of the air hole of the proposed PCFs increases, which nevertheless can be overcome by increasing the ring number or the area of the air holes in the fiber cladding.

Abstract: A two-dimensional electro-elastic analysis is performed on a transversely isotropic piezoelectric material with an elliptical hole, which is subjected to remote uniform shear forces, and remote electric field. Based on the impermeable electric boundary conditions, close form solutions are obtained by using the complex potentials method. Taking PZT-4 ceramic into consideration, the stress distributions around the neighborhood of the elliptical hole are given. It is shown that the hole geometry and the electric field are responsible for the shielding effect, there are sharp stress concentration near the hole.

Abstract: A two-dimensional electromechanical analysis is performed on a transversely isotropic piezoelectric material containing an elliptical hole, which is subjected to uniform compressive forces with intensity q acting on the edge of the hole and uniform electric displacement fields at infinity. Based on the impermeable electric boundary conditions, general electromechanical fields solution are obtained in the form of complex potentials.