In 1934 J. Leray proposed a regularization of the Navier-Stokes equations
whose limits were weak solutions of the NSE. Recently, a modification of the
Leray model, called the Leray-alpha model, has atracted study for turbulent
flow simulation. One common drawback of Leray type regularizations is their low
accuracy. Increasing the accuracy of a simulation based on a Leray
regularization requires cutting the averaging radius, i.e., remeshing and
resolving on finer meshes. This report analyzes a family of Leray type models
of arbitrarily high orders of accuracy for fixed averaging radius. We establish
the basic theory of the entire family including limiting behavior as the
averaging radius decreases to zero, (a simple extension of results known for
the Leray model). We also give a more technically interesting result on the
limit as the order of the models increases with fixed averaging radius. Because
of this property, increasing accuracy of the model is potentially cheaper than
decreasing the averaging radius (or meshwidth) and high order models are doubly
interesting