Napoved kavitacije v črpalki s 3D ozobjem

Bratuš, Špela (author), Hočevar, Marko (mentor), Petkovšek, Martin (co-mentor)

Magistrsko delo obravnava pojav kavitacije v zobniški črpalki s 3D aksialnim ozobjem. Z metodo neto pozitivne sesalne višine so bile določene kritične obratovalne točke črpalke. Metoda definira padec hidravlične moči črpalke kot merilo za pojav kavitacije. Izvedene so bile hidravlične meritve za določitev zahtevane neto pozitivne sesalne višine črpalke. Na njih je bila nato zasnovana enačba za napoved kritičnega podtlaka v odvisnosti od pretoka in vrtilne frekvence. Med izvajanjem hidravličnih meritev je bila postavljena hipoteza, da se kavitacija pojavi preden zaznamo padec hidravlične moči. Predpostavka temelji na zaznanem povišanju hrupa pred kritičnim podtlakom, ki ga določimo z metodo preko neto pozitivne sesalne višine. Dano hipotezo potrdimo z meritvami hrupa in vibracij.

• Language: Slovenian
• Keywords: zobniška črpalka, kavitacija, neto pozitivna sesalna višina, kavitacijski hrup, vibracije
• Work type: Master's thesis/paper
• Typology: 2.09 - Master's Thesis
• Organization: FS - Faculty of Mechanical Engineering
• Place of publishing: Ljubljana
• Publisher: [Š. Bratuš]
• Year: 2023
• Number of pages: XXIV, 77 str.
• PID: 20.500.12556/RUL-148981
• UDC: 532.528:621.664(043.2)
• COBISS.SI-ID: 185478147
• Publication date in RUL: 02.09.2023

Secondary language

• Language: English
• Title: Prediction of cavitation in gear pump

Abstract

Master thesis focuses on cavitation in gear pump with 3D axial gear teeth. Method of net positive suction head was used to determine critical operating points of the pump. This method defines drop in pump hydraulic power as cavitation criteria. Hydraulic measurements were obtained for purpose of calculating required net positive suction head of the pump. These represent the basis for further development of equation that predicts critical pressure in relation to flow and rotational speed. During measurements we notice increase in noise of the pump before we can observe hydraulic power drop. It can be assumed that cavitation occurs before we can detect it with method of net positive suction head. This hypothesis is then confirmed by noise and vibration measurements.

• Keywords: gear pump, cavitation, net positive suction head, cavitation noise, vibrations