In this paper we describe the implementation and development of a new Taylo
r-Galerkin finite-element scheme within an unstructured/hybrid, parallel so
lver. The scheme has been specifically conceived for unsteady LES: it is th
ird-order in space and time and has a low dissipative error. Minimal additi
onal CPU costs are achieved by using a new approximation of the finite-elem
ent integrals and a simple iterative method for the approximate inversion o
f the modified mass matrix. Basic convective tests are carried out in 2 and
3 dimensions for arbitrary elements. Numerical estimates of the order of c
onvergence are presented on regular and perturbed grids. Finally, test case
s that are relevant to LES are carried out, and these clearly demonstrate t
he important improvements that our new scheme offers relative to a selectio
n of existing methods. (C) 2000 Academic Press.