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Level-Set Interface Description Approach for Thermal Phase Change of Nanofluids.
Ali Yahyaee1, Amir Sajjad Bahman1, Klaus Olesen2
1Department of Energy, Aalborg University, 9220 Aalborg, Denmark.
Nanomaterials (Basel, Switzerland)
|July 9, 2022
Summary
Simulating nanofluid phase change is challenging due to interface location inaccuracies. A coupled level-set and VOF (CLSVOF) method improves simulation accuracy for thermal phase change phenomena but increases processing time.
Area of Science:
- Computational fluid dynamics (CFD)
- Multiphase flow simulations
- Nanofluid heat transfer
Background:
- Simulating thermally driven phase change in nanofluids presents challenges in accurately locating the gas-liquid interface.
- The Volume of Fluid (VOF) method, widely used in CFD, suffers from inaccurate curvature calculations leading to non-physical velocities near the interface.
- Existing methods struggle with precision in complex nanofluid thermal phase change simulations.
Purpose of the Study:
- To implement and evaluate a coupled level-set and VOF (CLSVOF) method for simulating nanofluid phase change.
- To compare the performance of CLSVOF against the standard VOF method in terms of accuracy and computational cost.
- To assess the impact of nanoparticles on fluid behavior during phase change using experimental correlations.
Main Methods:
- Implementation of the CLSVOF method within the OpenFOAM® framework.
- Comparative analysis of CLSVOF and VOF methods for various phase change scenarios.
- Incorporation of nanoparticle effects on base fluid properties using established literature correlations.
Main Results:
- The CLSVOF method demonstrated significantly more precise curvature calculations compared to the VOF method.
- Simulations using CLSVOF showed improved agreement with analytical and benchmark solutions.
- The enhanced accuracy of CLSVOF came at the cost of increased computational processing time.
Conclusions:
- The CLSVOF method offers a viable solution for enhancing the accuracy of nanofluid phase change simulations.
- While computationally more intensive, CLSVOF provides superior interface capturing and curvature calculation.
- This advancement is crucial for reliable simulations of complex thermal phenomena involving nanofluids.
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