PAT optimization

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F68407700%3A21110%2F24%3A00378111" target="_blank" >RIV/68407700:21110/24:00378111 - isvavai.cz</a>

Result on the web

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DOI - Digital Object Identifier

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Result language

čeština

Original language name

OPTIMALIZACE VNITŘNÍCH TVARŮ ČERPADEL V TURBÍNOVÉM REŽIMU

Original language description

Pumps in turbine mode (PAT) are used worldwide in micro-, mini- and small hydropower plants. Thanks to serial production and easy installation, they offer an economically efficient solution. Nevertheless, the use of PAT has some disadvantages – in particular, lower efficiency, limited flow control, and a sharp efficiency curve compared to standard turbines. In addition, it is difficult to select the appropriate pump for specific head and flow conditions, leading to further efficiency reductions when operating outside the best efficiency point (BEP). To minimize these shortcomings while preserving the advantages of PAT, we propose an innovative approach based on a standard series-produced pump or from a pump that is already located in the given location. Most of the hydraulic parts of the pump (spiral housing, bearings, seals) and the electrical part are preserved. To improve the hydraulic parameters for given site parameters (head, flow, and generator speed), the original pump impeller is replaced with a new runner. The shape is optimized for the site respecting turbine operational mode. Optimizing the new runner’s shape starts by finding the exact 3D shape of the internal surfaces of the pump using 3D scanning, which allows the creation of a digital spatial model. Subsequently, a multi-criteria optimization of the new runner is carried out using the CAESES parametric 3D modeller connected to Ansys CFX. The fully parametric model enables effective optimization while taking into account existing pump parts, hydraulic requirements and any other constraints. The result of this optimization process is a PAT unit for small hydropower plants that keeps the advantages of low investment cost, and significantly improved hydraulic parameters compared to original PAT. The increase of hydraulic efficiency by approximately 15% is demonstrated on the example of real HPP site with replaced old standard pump impeller with optimized runner for turbine operation. The optimization of the shape of the runner blades for this location was also carried out with regard to the avoid cavitation, noise and vibration. This will reduce mechanical stress and thereby extend the lifetime of the new stainless-steel runner.

Czech name

OPTIMALIZACE VNITŘNÍCH TVARŮ ČERPADEL V TURBÍNOVÉM REŽIMU

Czech description

Pumps in turbine mode (PAT) are used worldwide in micro-, mini- and small hydropower plants. Thanks to serial production and easy installation, they offer an economically efficient solution. Nevertheless, the use of PAT has some disadvantages – in particular, lower efficiency, limited flow control, and a sharp efficiency curve compared to standard turbines. In addition, it is difficult to select the appropriate pump for specific head and flow conditions, leading to further efficiency reductions when operating outside the best efficiency point (BEP). To minimize these shortcomings while preserving the advantages of PAT, we propose an innovative approach based on a standard series-produced pump or from a pump that is already located in the given location. Most of the hydraulic parts of the pump (spiral housing, bearings, seals) and the electrical part are preserved. To improve the hydraulic parameters for given site parameters (head, flow, and generator speed), the original pump impeller is replaced with a new runner. The shape is optimized for the site respecting turbine operational mode. Optimizing the new runner’s shape starts by finding the exact 3D shape of the internal surfaces of the pump using 3D scanning, which allows the creation of a digital spatial model. Subsequently, a multi-criteria optimization of the new runner is carried out using the CAESES parametric 3D modeller connected to Ansys CFX. The fully parametric model enables effective optimization while taking into account existing pump parts, hydraulic requirements and any other constraints. The result of this optimization process is a PAT unit for small hydropower plants that keeps the advantages of low investment cost, and significantly improved hydraulic parameters compared to original PAT. The increase of hydraulic efficiency by approximately 15% is demonstrated on the example of real HPP site with replaced old standard pump impeller with optimized runner for turbine operation. The optimization of the shape of the runner blades for this location was also carried out with regard to the avoid cavitation, noise and vibration. This will reduce mechanical stress and thereby extend the lifetime of the new stainless-steel runner.

Type

O - Miscellaneous

CEP classification

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OECD FORD branch

20302 - Applied mechanics

Project

<a href="/en/project/TK05020037" target="_blank" >TK05020037: Optimization of variable speed PAT</a><br>

Continuities

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

Publication year

2024

Confidentiality

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