Numerical study of transition hydraulic jumps in different types of stilling basins using lattice Boltzmann methods DOI

Wenjuan Gou,

Zhaochuan Shen

Physics of Fluids, Journal Year: 2024, Volume and Issue: 36(11)

Published: Nov. 1, 2024

Transition hydraulic jumps, also known as low-Froude number have been less studied compared to high Froude despite their significance in high-discharge and low-head dams. A three-dimensional (3D) Lattice Boltzmann method simulation was conducted investigate submerged transition jumps both normal expanded stilling basins, focusing on turbulent flow characteristics such velocity fields, vorticity features, pressure fluctuations, coherent structures. In two symmetric separated rollers were observed, with the detaching from jump width of basin increased. The length roller basins is observed Lr/Ht = 6.19, while it decreased 4 because occurrence lateral diffusion toward sidewalls. vortex structures y- z-vortical analyzed, shear layers are captured using iso-surface magnitude ω 6.5. To further describe internal structure turbulence within jump, qualitatively examined Ω criterion that third generation identification technique. Pressure fluctuations described root mean square (RMS), first presented. High patches RMS found fields at bottom noted effects make great contributions fluctuations. Distribution fluctuation different types analyzed. peak value occurs ogee region weir, specifically x/L −0.2, mainly affected by expansion. Bottom decreases following order: Normal, 5 m gradual expansion, 10 sudden due This research introduces an innovative numerical approach studying offering valuable insights for engineering applications.

Language: Английский

Nanofluid heat transfer and machine learning: Insightful review of machine learning for nanofluid heat transfer enhancement in porous media and heat exchangers as sustainable and renewable energy solutions DOI Creative Commons

Tri W.B. Riyadi,

Safarudin Gazali Herawan,

Andy Tirta

et al.

Results in Engineering, Journal Year: 2024, Volume and Issue: unknown, P. 103002 - 103002

Published: Sept. 1, 2024

Language: Английский

Citations

4

Comparative performance of cubic and cylindrical graphite heat exchangers: A study using computational fluid dynamics DOI
Alireza Nasrollahi, Asal Sami, Mohammad Mehrpooya

et al.

Physics of Fluids, Journal Year: 2025, Volume and Issue: 37(3)

Published: March 1, 2025

Graphite towers, a type of graphite heat exchanger (HX), are extensively utilized in the chemical and steel industries for exchange between corrosive fluids. These towers available various sizes geometries, primarily cylindrical cubic. This paper presents novel computational fluid dynamics simulation elements, results show that cubic block has better performance comparing one. It also examines constructed from these elements. study reveals overall coefficient transfer tower with side equal to diameter cylinder is 9% higher than tower. Consequently, temperature difference inlet outlet process 37% greater However, pressure drop service 2.4 times same Analyzing individual elements indicates exit least efficient model surpasses most by 2.6%. findings underscore superior capabilities despite increased drop, offering valuable insights optimizing design HXs. investigates influence geometry on transfer, addressing gap previous research. By systematically analyzing geometric configurations, we present calculations profiles, deeper into interplay thermal performance.

Language: Английский

Citations

0

A vertical multi-tube latent thermal energy system with tube inserts and radial fins: Experimental and CFD modeling study DOI Creative Commons

Jiani Wu,

Janne Dragsted, Simon Furbo

et al.

Journal of Energy Storage, Journal Year: 2025, Volume and Issue: 122, P. 116652 - 116652

Published: April 21, 2025

Language: Английский

Citations

0

Deep Learning-Based Rapid Flow Field Reconstruction Model with Limited Monitoring Point Information DOI Creative Commons
Ping Wang,

Guangzhong Hu,

Wenli Hu

et al.

Aerospace, Journal Year: 2024, Volume and Issue: 11(11), P. 871 - 871

Published: Oct. 24, 2024

The rapid reconstruction of the internal flow field within pressure vessel equipment based on features from limited detection points was significant value for online monitoring and construction a digital twin. This paper proposed surrogate model that combined Proper Orthogonal Decomposition (POD) with deep learning to capture dynamic mapping relationship between sensor point information global state during operation, enabling temperature velocity field. Using POD, order tested reduced by 99.75%, 99.13%, effectively decreasing dimensionality Our analysis revealed first modal coefficient snapshot data, after decomposition, had higher energy proportion compared along more pronounced marginal effect. indicates modes need be retained achieve total proportion. By constructing CSSA-BP represent coefficients fields data collected points, comparison made BP method in reconstructing shell-and-tube heat exchanger. yielded maximum mean squared error (MSE) 9.84 reconstructed field, absolute (MAE) 1.85. For MSE 0.0135 MAE 0.0728. errors were 4.85%, 3.65%, 4.29%, respectively. 17.72%, 11.30%, 16.79%, indicating established this study has high accuracy. Conventional CFD simulation methods require several hours, whereas here can rapidly reconstruct 1 min training is completed, significantly reducing time. work provides new quickly obtaining under offering reference development twins equipment.

Language: Английский

Citations

1

Flow Control of Flow Boiling Experimental System by Whale Optimization Algorithm (WOA) Improved Single Neuron PID DOI Creative Commons
Yan Li, Miao Qian,

Dawei Dai

et al.

Actuators, Journal Year: 2024, Volume and Issue: 14(1), P. 5 - 5

Published: Dec. 27, 2024

In the present study, to address issue of flow rate instability in boiling experimental system, a adaptive control system is developed using single-neuron PID algorithm, enhanced with whale optimization algorithm (WOA) for parameter tuning. A recursive least-squares online identification method integrated adapt varying operating conditions. The simulation results demonstrate that step response WOA-improved significantly mitigates overshoot, mere 0.31% overshoot observed, marking reduction 98.27% compared traditional control. output curve closely aligns sinusoidal signal, exhibiting an average absolute error 0.120, which lower than (0.209) and fuzzy (0.296). (1.01 s) exhibited faster return stable state (2.46 (1.28 s). Finally, effectiveness validated through practical application. that, algorithms, achieves stability 9.9848 standard 0.0914394. It exhibits superior performance, including rise settling times, higher stability.

Language: Английский

Citations

1

Numerical study of transition hydraulic jumps in different types of stilling basins using lattice Boltzmann methods DOI

Wenjuan Gou,

Zhaochuan Shen

Physics of Fluids, Journal Year: 2024, Volume and Issue: 36(11)

Published: Nov. 1, 2024

Transition hydraulic jumps, also known as low-Froude number have been less studied compared to high Froude despite their significance in high-discharge and low-head dams. A three-dimensional (3D) Lattice Boltzmann method simulation was conducted investigate submerged transition jumps both normal expanded stilling basins, focusing on turbulent flow characteristics such velocity fields, vorticity features, pressure fluctuations, coherent structures. In two symmetric separated rollers were observed, with the detaching from jump width of basin increased. The length roller basins is observed Lr/Ht = 6.19, while it decreased 4 because occurrence lateral diffusion toward sidewalls. vortex structures y- z-vortical analyzed, shear layers are captured using iso-surface magnitude ω 6.5. To further describe internal structure turbulence within jump, qualitatively examined Ω criterion that third generation identification technique. Pressure fluctuations described root mean square (RMS), first presented. High patches RMS found fields at bottom noted effects make great contributions fluctuations. Distribution fluctuation different types analyzed. peak value occurs ogee region weir, specifically x/L −0.2, mainly affected by expansion. Bottom decreases following order: Normal, 5 m gradual expansion, 10 sudden due This research introduces an innovative numerical approach studying offering valuable insights for engineering applications.

Language: Английский

Citations

0