Freesurfaceflowproblemsinvolvinglargefreemotionsareanalysedusingfiniteelementtechniques.InsolvingtheseproblemsanArbitraryLagrangian-Eulerian(ALE)kinematicaldescriptionofthefluiddomainisadopted,inwhichthenodalpointscanbedisplacedindependentlyofthefluidmotion.Anewmeshtracingmethodisproposedinthispaper.Toconfirmtheeffectivenessofthenewmethod,solitarywavepropagationisanalysedandthenumericalresultsarecomparedwiththeanalyticalresults.ThebehaviouroftheviscousfluidflowwithafreesurfaceisexpressedbytheunsteadyNavier-Stokesequation.Fornumericalintegrationintimethevelocitycorrectionfractionalstepmethodisused.
