Isoparametric Elements

In Section 11.2, to map a rectangular element to a unit square, a constant transformation rule is applied element by element. Now the same (= iso) shape functions φ, which are chosen to describe the physical behavior of an element, may also be used to describe the element geometry. This idea is first published by Taig [95] and later on introduced by Irons and Zienkiewicz [52] as isoparametric element concept.