Volute throat area and wall modelling influence on the numerical performances of a very low specific speed pump

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216305%3A26210%2F21%3APU141176" target="_blank" >RIV/00216305:26210/21:PU141176 - isvavai.cz</a>

Result on the web

<a href="https://iopscience.iop.org/article/10.1088/1755-1315/774/1/012007" target="_blank" >https://iopscience.iop.org/article/10.1088/1755-1315/774/1/012007</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1088/1755-1315/774/1/012007" target="_blank" >10.1088/1755-1315/774/1/012007</a>

Result language

angličtina

Original language name

Volute throat area and wall modelling influence on the numerical performances of a very low specific speed pump

Original language description

Low specific speed pumps find applications in a broad range of domains, but suffer from a low efficiency and a risk of head instability close to shut-off. The numerical computations on these pumps performed in the last years have shown discrepancies with experimental results. Recent studies suggest that the use of wall-functions underpredicts the losses of these pumps, especially at overload. The reason has been attributed to a detachment zone downstream the volute tongue, not well captured with the wall-function approach. This paper focuses on the influence of the volute casing on a pump with a specific speed of 8.9 on two issues. First, the influence of the wall modelling approach relatively to the low-Reynolds number method on the performance prediction is discussed. The results are, as expected, an underprediction of the losses when the wall-function approach is used. With a larger volute, the difference between the two wall modeling approaches is smaller. Secondly, the influence of the volute throat area enlargement on the pump performances is discussed. Both the head and efficiency are improved at the design point and at overload with an increased volute throat area. However the part-load head decreases and the head flattens. The study of the flow at part-load, in the region at the outlet of the impeller reveals that with a larger volute, larger flow exchanges are present, contributing to additional mixing losses and head loss.

Czech name

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Czech description

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Type

D - Article in proceedings

CEP classification

—

OECD FORD branch

20302 - Applied mechanics

Project

<a href="/en/project/EF16_026%2F0008392" target="_blank" >EF16_026/0008392: Computer Simulations for Effective Low-Emission Energy Engineering</a><br>

Continuities

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)<br>S - Specificky vyzkum na vysokych skolach

Publication year

2021

Confidentiality

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

Article name in the collection

IOP Conference Series-Earth and Environmental Science

ISBN

—

ISSN

1755-1307

e-ISSN

—

Number of pages

9

Pages from-to

012007-012007

Publisher name

IOP Publishing

Place of publication

neuveden

Event location

Lausanne

Event date

Mar 21, 2021

Type of event by nationality

WRD - Celosvětová akce

UT code for WoS article

000712043400007