Development of nonlinear finite element method program provided the h-version adaptive Mesh division function

; Tsukimori, Kazuyuki

PNC TN9410 98-069, 128 Pages, 1998/05

PNC-TN9410-98-069.pdf:2.55MB

There is a growing tendency to need structural analysis aided expert system, which adopts advanced analysis techniques and is useful adaptive design of large reactor. This report describes about development of the h-version adaptive mesh division function based on Yuge & Iwai method. From points of view about securing of analysis precision, reduction of work to make analysis data and decrease in calculation costs, to analyze smoothly the nonlinear problems is the main object of this system. The h-version adaptive mesh technique is the method that increases locally finite element mesh density, depending on dividing the elements that the absorbed energy quantity exceeds a standard value every increment step. We developed this h-version adaptive mesh division function and incorporate it in the general nonlinear finite element code. For the function this system has, we show the following. (1)It is possible to apply this system to the thermos elastic-plastic nonlinear problem. (2)The provided finite elements (a)4-Node Quadrilateral Plane-Stress Element (b)4-Node Quadrilateral P1ane-Strain Element (c)4-Node Quadrilateral Axisymmetric Solid Element (d)4-Node Layered Shell Element (3)The provided constitutive model (a)Ono-model (b)kinetic hardening rule (c)ORNL 10 cycles hardening rule (4)The repetition technique : Newton-Raphson technique (5)The application possible force type (a)The concentrated forces (b)The distributed forces (c)The self forces (d)The temperature forces (6)It is possible to apply the cyclic repetition force. (7)The dividing the elements technique (a)Rectifying the strain of the element shape depending on the aspect ratio (b)Dividing the elements that the absorbed energy quantity exceeds a standard value every increment step. (c)Add the function of input the plural absorbed energy quantity that is the estimate value of the division elements. The programming and giving the tests about this system was put into by RCCM.