Journal of Applied Sciences1812-56541812-5662Asian Network for Scientific Information10.3923/jas.2009.2501.2518EL-EmamNameer N.YousifNadia Y.122009914This study presents a new technique based on back-propagation
algorithm and Adaptive Neural Networks (ANN) to compute a compressible flow
represented by velocity profiles through symmetrical double steps channels.
The technique adopts a new clustering algorithm named a Dual-level Clustering
(DC), which is based on the speed of flow, the flow deflection and the average
of false diffusion error .
A learning system of three stages is employed, whose first two stages are run
simultaneously while the third works as an optimizer stage. The first stage
constructs a finite element analysis employing adaptive incremental loading
to select appropriate patterns effectively. The second stage concerns an ANN
with Modified Adaptive Smoothing Error (MASE), whereas the third stage is to
classify a set of patterns into DC to reduce the effect of errors. The proposed
training algorithm is fast enough and the simulation results of the learning
system are in harmony with the available previous works. The success of such
algorithm can be attributed to three reasons. The first is the employment of
ANN that is an excellent approximator, especially if training starts from laminar
flow patterns. The second reason is the speed of training due to the use of
ANN with learning rate Î± = 0.7 on the few number of selected patterns equal
to 464 and the third reason is satisfying the stability and the accuracy for
high range of Reynolds numbers (Re) Re = 4500 due to the use of MASE and DC
based on false diffusion error.]]>Creuse, E. and I. Mortazavi,2004Eker, E. and A. Serhat,2006EL-Emam, N.N.,2006EL-Emam, N.N. and R.A. Shaheed,2008Frean, M., M. Lilley and P. Boyle,2006Frossyniotis, D.S., C. Pateritsas and A. Stafylopatis,2005Glowinski, R. and P. Neittaanmaki,2008Golcu, M.,2006He, Z., X. Xu and S. Deng,2005Hovakimyan, N., F. Nardi and A.J. Calise,2002Kaczmarczyk, L. and Z. Waszczyszyn,2005Lefik, M. and M. Wojciechowski,2005Meybod, M.R. and H. Beigy,2002Payne, S.J.,2006Rajkumar, T. and J. Bardina,2002Silvestre, M.R., S.M. Oikawa, F.H.T. Vieira and L.L. Ling,2008Singh, R.P. and Z. Li,2007Yu, W. and A. Morales,2005Vodinh, L., B. Podvin and P. Le Quéré,2005