The Effects of Stage Number on Pump Operation Characteristics in Vertical Line Shaft Deep Well Irrigation Pumps

In this study, the effect of stage number on operation characteristics of three different diameter deep well pumps used in irrigation pumping plants was researched. The pumps were tested with 6 stages number that manufacturer offered at three different RPM. The RPM where maximum efficiency obtained assumed as optimum RPM. The working characteristics of pumps at (1 – 6) stages number were determined. The tests were performed according to ISO 2548 regulations and as three repetitions. According to the result of the test, statistical analysis were applied on the function of the stage number, power and pressure in full closed valve (FCV) and flow and best efficiency in full opened valve (FOV). According to the results of the research, on condition that the shaft diameter and impeller dimension are stable, the effect of stage number variation on power pressure and efficiency was significant whereas insignificant on flow. Key word: Turbine deep well pumps, pump performance, stage number, pump efficiency Derin Kuyu Pompalarinda Kademe Sayisinin Pompa Isletme Karakteristiklerine Etkisi Ozet: Bu calismada; pompaj tesislerinde kullanilan uc farkli captaki derin kuyu pompalarinin kademe sayisinin isletme karakteristigi uzerine etkisi arastirilmistir. Pompalar, once 6 kademe sayisinda firmanin onerdigi uc degisik devirde denenmistir. Sonra, her pompa icin en yuksek verimin saglandigi devir sayisi, o pompa icin optimum devir sayisi olarak kabul edilmistir. Daha sonra, her uc pompa kendi optimum devir sayisinda olmak uzere alti ayri (1-6) kademe sayisindaki isletme karakteristikleri belirlenmistir. Denemeler ISO 2548’e gore gerceklestirilmis ve uc tekerrurlu olarak yurutulmustur. Denemelerin sonucuna gore, kademe sayisinin fonksiyonu olarak, tam kapali vanadaki (TKV) guc ve basinc, tam acik vanadaki (TAV) debi ve en yuksek verim degerleri uzerine istatistiksel analizler yapilmistir. Calismanin sonucuna gore, mil capi ve cark olculeri sabit kalmasi kosuluyla kademe sayisinin degisiminin guc, basinc ve verim uzerine etkisi onemli, debi uzerine etkisi ise onemsiz bulunmustur. Anahtar kelimeler: Turbin derin kuyu pompalari, pompa performansi, kademe sayisi, pompa verim