Investigation of water hammer problems and potential solutions in pump discharge lines


Tezin Türü: Yüksek Lisans

Tezin Yürütüldüğü Kurum: Orta Doğu Teknik Üniversitesi, Fen Bilimleri Enstitüsü, Fen Bilimleri Enstitüsü, Türkiye

Tezin Onay Tarihi: 2019

Tezin Dili: İngilizce

Öğrenci: RECEP ÇAĞRI ERDEM

Danışman: Zafer Bozkuş

Özet:

Disturbance in boundary conditions of a hydraulic system could cause rapid change in flow velocity in confined pipe systems. Pressure wave leading to an event called water hammer may occur as a consequence of that disturbance. Water hammer could lead to catastrophic failures on the hydraulic systems. Thus, proper protection measures should be defined and installed in the system before it is put into operation. The aim of this study is to analyze a pumped discharge line and ensure its safe operation against water hammer. For this purpose, the pump discharge line is examined with a transient software called HAMMER, in which unsteady partial differential equations of the pipe flow are solved with a widely used Method of Characteristics (MOC). Pump trip (shut-down) scenarios are tested in the analyses. High pressures that could cause bursting of the pipe and low pressures which lead to cavitation are observed in unprotected version of the hydraulic system. Afterwards, air chambers, flywheels, one-way surge tank and air valve are operated in separate and combined form. Lastly, comparison of the results is done with and without protection devices.