Validation and analysis of turbulence modeling in pipe elbow under secondary flow conditions

Carloni, Ana Cristina Neves; Conde, Kevin Eduardo de; PANTALEAO, ALUISIO; Azevedo, João Luiz F.; Rade, Domingos A.

doi:10.1007/s40430-022-03899-9

Cited by 7 publications

(2 citation statements)

References 24 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…A test calculation was performed with the k-Epsilon turbulence model. However, due to the limited validation possibilities, the SST model was finally used, which should better describe the secondary flow in the penstock [21]. The calculation step is AutoTimescale-conservative with a factor of 0.25.…”

Section: Numerical Setupmentioning

confidence: 99%

“…The planned turbulence model is SST, and for the automatic wall function, all the first cells should be located in the log-law region near the wall [20] with y+ value between 30 and 200. The relationship between y+, the turbulence model and the wall function is discussed in detail Carloni et al [21] or Nicolle et al [22] A simplified mesh dependency test was performed on the computational grid size for 2 million and approximately 7.3 million elements (see details of mesh parts in Figure 3). The mesh size effect on the value of the hydraulics losses and the behaviour of the velocity field in the penstock was monitored.…”

mentioning

confidence: 99%

See 1 more Smart Citation

CFD as a Decision Tool for Pumped Storage Hydropower Plant Flow Measurement Method

Souček

Nowak

Kantor

et al. 2023

Water

View full text Add to dashboard Cite

Suitable and accurate flow measurement in pumped storage hydropower plants (PSP) is a challenging task due to the entirely different hydraulic behaviour of the penstock. This study presents a novel approach to choosing a suitable flow measurement method and position. The focus is on the flow measurement in a specific short penstock of the largest peak-load hydropower plant, Orlík, after its transformation to a PSP. Our approach is based on three main pillars: numerical modelling of fluid flow (ANSYS CFX), standards, and scientific literature. First, the steady-state numerical model output for the current state is compared to historical measurements of point velocities using current meters and measured hydraulic losses in the penstock. Subsequently, for the planned conversion to the reversible Francis turbine, including shape modifications of the flow paths, a steady numerical simulation of the flow in the penstock was performed in both turbine and pump modes. By analysing the resulting pressure and velocity fields and comparing them to standards and scientific literature, the values of the uncertainty in the flow measurement were calculated. The outcome is a straightforward evaluation and comparison of three main flow measurement methods: current meter, pressure–time, and ultrasonic transit time.

show abstract

Section: Numerical Setupmentioning

confidence: 99%

mentioning

confidence: 99%