DNA Equilibrium Configuration Base On The Absolute Nodal Coordinate Formulation

The special nature of the DNA molecule makes the mechanical model don’t like the generalelastic rod. It has the characteristics of extreme elongated and large deformation. The beam, plate,shell and other elements base on Absolute nodal coordinate method are isoparametric elements. Thesystem dynamics equations of the flexible body can accurately describe the rigid body motion and thedeformation of its own structure and within the kinetic equation. The system mass matrix remainssymmetrical and constant. Therefore, the absolute nodal coordinate method to study the DNA of theequilibrium configuration becomes feasible.The plane and space elastic force and the Jacobian matrix of elastic force respect to the beamelement are derivative base on the Absolute Nodal Coordinate Method. In this paper, use the absolutenodal coordinate method to establish the mechanical model of the DNA molecule, consider theinfluence of interface energy and the discrete equilibrium equation consider the influence of interfaceenergy is derived. Investigate the influence of the interfacial energy，initial configuration and elasticstrain energy on the equilibrium configuration of the DNA molecule, and plays a dominantinfluencing factors on stable configurations.The research results show that the absolute nodal coordinate method can well describe theflexible body systems which has a wide range of spatial movement coupled with large deformation ofits own structure. The thin elastic rod model established by Absolute Nodal Coordinate Method coulddescribe the mechanical behavior of the DNA molecule. The configuration of the DNA molecule isdetermined by the interface and its elastic strain energy. Interface traction is one of the factors thatlead to DNA molecular chain folding and unfolding.