TY - JOUR JF - mdrsjrns JO - MCEJ VL - 15 IS - 3 PY - 2015 Y1 - 2015/9/01 TI - Control point grid improvement in isogeometric analysis of axisymmetric structures using error estimation methods based on stress recovery TT - بهبود شبکه نقاط کنترل در تحلیل ایزوژئومتریک سازه های متقارن محوری با استفاده از روشهای تخمین خطا مبتنی بر بازیافت تنش N2 - This research is devoted to the adaptive solution and control point net improvement of axisymmetric problems in isogeometric analysis using the error estimation based methods for stress recovery. For this purpose, after the calculation of the energy norm, the estimated value of error in the vicinity of each control point is assigned to the neighboring members of a hypothetical truss-like structure as an artificial thermal gradient. By analysis of this network of rods under the temperature variations a new arrangement of control points is obtained. Repeating this process of thermal isogeometric analysis will eventually lead to a better distribution of errors in the domain of the problem and results in an optimal net of control points for the calculation of the integrals. To demonstrate the performance and efficiency of the proposed method, two axisymmetric elasticity problems with available analytical solutions are considered. The obtained results indicate that this innovative approach is effective in reducing errors of axisymmetric problems and can be employed for improving the accuracy in the context of the isogeometric analysis method. Innovated method of this research focuses on adaptive analysis and Network improving of axisymmetric problems in isogeometric analysis using error estimation methods based on stress recovery. For this purpose after calculation the energy norm, estimated value of error in the vicinity of control points is assigned to each rod as the thermal gradient. Thus after analyzing the hypothetical rods network under the temperature changes a new arrangement of control points and knot vectors can be obtained. The use of multi-cycle of this process in isogeometric analysis will lead to a better distribution of errors in the domain and thus achieve optimal network to calculate the integrals. To measure the efficiency of this method and demonstrate the increased carefully in axisymmetric problems, which has the analytical solution, two elasticity problem is evaluated. The results show that innovative network improving method has good efficiency to reduce the error rate and can be used to increase the accuracy of isogeometric analysis results. Innovated method of this research focuses on adaptive analysis and Network improving of axisymmetric problems in isogeometric analysis using error estimation methods based on stress recovery. For this purpose after calculation the energy norm, estimated value of error in the vicinity of control points is assigned to each rod as the thermal gradient. Thus after analyzing the hypothetical rods network under the temperature changes a new arrangement of control points and knot vectors can be obtained. The use of multi-cycle of this process in isogeometric analysis will lead to a better distribution of errors in the domain and thus achieve optimal network to calculate the integrals. To measure the efficiency of this method and demonstrate the increased carefully in axisymmetric problems, which has the analytical solution, two elasticity problem is evaluated. The results show that innovative network improving method has good efficiency to reduce the error rate and can be used to increase the accuracy of isogeometric analysis results. SP - 105 EP - 118 AU - mirzakhani, aboozar AU - Hassani, Behrooz AU - khanlari, karen AU - ga, a AD - Faculty member KW - Isogeometric analysis KW - Control Point KW - Adaptive Analysis KW - Axisymmetric KW - Error Norm UR - http://mcej.modares.ac.ir/article-16-3051-en.html ER -