Influence of runner cone profile and axial water jet injection in a low head Francis turbine at part load
2022 (English)In: Sustainable Energy Technologies and Assessments, ISSN 2213-1388, E-ISSN 2213-1396, Vol. 50, article id 101810Article in journal (Refereed) Published
Abstract [en]
Development of rotating vortex rope (RVR) at part load (PL) operation is a source of pressure fluctuations in draft tube and power swings, which may lead to runner failure under extreme conditions. Fluid injection methodologies like air and water injection may be employed to mitigate the RVR and the pressure pulsations associated with it. A small turbine test rig is being developed at IIT Roorkee (India) to study the effect of the fluid injection measures (air/ water) in the Francis turbine. The present work summarizes a preliminary numerical investigation of the runner cone design and water jet injection to be used in the test rig. The runner cone is modified to incorporate provisions for axial water jet injection. Two different runner cone designs have been compared based on power output, efficiency, pressure recovery, and pressure pulsations in the draft tube for four different jet discharges. The water jet affects both the magnitude and the frequency of the pressure pulsations associated with RVR, and improves the overall efficiency. The results also indicate that the water jet injection may not always be effective and may increase pressure fluctuations in some cases.
Place, publisher, year, edition, pages
Elsevier, 2022. Vol. 50, article id 101810
Keywords [en]
Hydropower, Francis turbine, Rotating vortex rope, Jet injection, Runner cone, Part-load operation
National Category
Fluid Mechanics and Acoustics
Research subject
Fluid Mechanics
Identifiers
URN: urn:nbn:se:ltu:diva-88188DOI: 10.1016/j.seta.2021.101810ISI: 000769920700009Scopus ID: 2-s2.0-85120166717OAI: oai:DiVA.org:ltu-88188DiVA, id: diva2:1616343
Note
Validerad;2021;Nivå 2;2021-12-02 (johcin);
Funder:Central Power Research Institute (CPRI), India, (CPR-1133-MID)
2021-12-022021-12-022022-04-21Bibliographically approved