Velocity profile influence on spiral vortex breakdown in diffuser

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216305%3A26210%2F08%3APU75583" target="_blank" >RIV/00216305:26210/08:PU75583 - isvavai.cz</a>

Výsledek na webu

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DOI - Digital Object Identifier

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Jazyk výsledku

angličtina

Název v původním jazyce

Velocity profile influence on spiral vortex breakdown in diffuser

Popis výsledku v původním jazyce

Flow in diffuser with circumferential velocity component is accompanied by spiral vortex breakdown for large diffuser divergence angles. This phenomenon, although being investigated for almost fifty years1,2, is not fully understood yet. Study of this problem is essential for example for design of hydraulic turbine draft tubes operating in part load conditions, where vortex breakdown causes severe pressure pulsations. It is well known that tangential velocity profile plays important role in origin and character of the vortex breakdown3. Aim of this paper is to find influence of tangential velocity profile on spiral vortex breakdown, not only in terms of swirl number, but also in terms of velocity profile shape. Experiment was carried out for diffuser divergence angle 11.6 degrees. Inlet circumferential velocity profile was provided by swirl generator with fixed blades. Velocity field was measured with LDA and pressure was recorded on the diffuser walls to obtain frequency spectra of th

Název v anglickém jazyce

Velocity profile influence on spiral vortex breakdown in diffuser

Popis výsledku anglicky

Flow in diffuser with circumferential velocity component is accompanied by spiral vortex breakdown for large diffuser divergence angles. This phenomenon, although being investigated for almost fifty years1,2, is not fully understood yet. Study of this problem is essential for example for design of hydraulic turbine draft tubes operating in part load conditions, where vortex breakdown causes severe pressure pulsations. It is well known that tangential velocity profile plays important role in origin and character of the vortex breakdown3. Aim of this paper is to find influence of tangential velocity profile on spiral vortex breakdown, not only in terms of swirl number, but also in terms of velocity profile shape. Experiment was carried out for diffuser divergence angle 11.6 degrees. Inlet circumferential velocity profile was provided by swirl generator with fixed blades. Velocity field was measured with LDA and pressure was recorded on the diffuser walls to obtain frequency spectra of th

Druh

O - Ostatní výsledky

CEP obor

BK - Mechanika tekutin

OECD FORD obor

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Projekt

<a href="/cs/project/GP101%2F06%2FP190" target="_blank" >GP101/06/P190: Tvarová optimalizace difuzoru se vstupní obvodovou složkou rychlosti</a><br>

Návaznosti

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Rok uplatnění

2008

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů