Byusignthepotentialmethodtoafluidfilledelastictube,weobtainedasolitarywavesolution.Comparedwithrecluetiveperturbationmethod,thismethodcanbeusedforlargeramplitudesolitarywaves.Theresultisinagreementwiththatofsmallamplitudeapproximationfromreduetiveperturbationmethodwhentheamplitudeissmallenough.