Saint-Venant torsion of cylindrical orthotropic elliptical cross section

This paper deals with the Saint-Venant torsion of elastic cylindrical orthotropic solid elliptical cross section. The origin of the cylindrical anisotropy coincides with the centroid of the elliptical cross section. By the use of principle of minimum of potential energy and principle of minimum of complementary energy approximate analytical solutions are derived for the torsion function and for the Prandtl's stress function. Obtained upper and lower bounds for the torsional rigidity show the accuracy of the derived approximate analytic solutions. (C) 2019 Elsevier Ltd. All rights reserved.