INVISCID AND VISCOUS-FLOW COMPUTATIONS BY MEANS OF A LAMBDA-METHODOLOGY - A REVIEW

The present paper provides a review of the more important results obta ined by the author, sometimes with co-authors, solving inviscid and vi scous compressible flows by means of a lambda methodology. In particul ar, an implicit numerical algorithm, called fast solver, has always be en applied. This methodology separately integrates the compatibility c onditions, written in terms of generalized Riemann variables, along ap propriate bicharacteristic lines. The multi-dimensional flow problem i s, thus, reduced to a sequence of simple quasi one-dimensional problem s. The merits of this approach are demonstrated by means of the applic ation of the method to the solution of three dimensional (3-D) subsoni c and transonic inviscid flows, of two-dimensional (2-D) and 3-D visco us flows and of the 2-D flow around a vertical axis wind turbine. In t he transonic case the shock wave is computed by means of a shock fitti ng technique, which enforces the proper shock jumps by an explicit use of the Rankine-Hugoniot equations; in the wind turbine case the blade s are represented in a time-averaged sense by means of an actuator por ous cylinder, having the turbine radius. The results are then compared with other numerical results and with experimental results. (C) 1997 Elsevier Science Ltd.