Parametric study on the water impacting of a free-falling symmetric wedge based on the extended von Karman’s momentum theory

Lu, Yujin; Buono, Alessandro Del; Xiao, Tianhang; Iafrati, Alessandro; Xu, Jinfa; Deng, Shuanghou; Chen, Jichang

doi:10.1016/j.oceaneng.2023.113773

“…Within the studies focused on free fall, two further modeling approaches are used with regard to the computation of drop-down velocity, i.e., from considering the forces that act on a falling body: the 6-degrees of freedom (DOF) and the computation of velocity upon a previous time step. More recently, the former approach was adopted within the parametric study of a 3D sphere impacting the free surface of water in Yu et al [4], being noted in the recent theoretical exposure in Lu et al [5].…”

Section: Introductionmentioning

confidence: 99%

Water Entry of a Heated Axisymmetric Vertical Cylinder

Cukrov,

Landek,

Sato

et al. 2023

Energies

2

0

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The computational model that is able to estimate the temperature distribution inside a solid specimen during the film boiling phase of immersion quenching (water entry) process has been presented in this paper. It is based on the prescribed initial temperatures of the solid specimen and the liquid quenchant. In addition, the turbulence effects have to be considered using the assumed turbulence kinetic energy value, i.e., the “frozen turbulence” approach, that remains constant thorough the simulation. The studied material is nickel alloy, Inconel 600, for which extensive experimental data are available. The work has been carried out using ANSYS Fluent computational fluid dynamics software and the methods for solution of Stefan problem by Eulerian two fluid VOF model. A satisfactory agreement between the experimental and the calculated data has been achieved, yielding thereby the computationally obtained data that fit to a great extent the prescribed error band of ±10% during the estimated film boiling phase of the immersion quenching process itself. It was, however, found that the temperature calculated in the center of a specimen fits this error band until reaching somewhere t < 6 s due to low presumed turbulence level in the domain. In addition, the explosion of the vapor phase after the body reaches the free surface of the quenchant has also been successfully tracked using the numerical simulation model proposed herein. The major novelty of the present research lies in the fact that a moving boundary problem has been successfully resolved in conjunction with, to a great extent, basic-principle-based heat and mass transfer in a turbulent flow conjugate heat transfer (CHT) numerical simulation using moderate computational resources.

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“…Within the studies focused on free fall, further two modeling approaches are used in regard of computation of drop-down velocity, i. e., from accounting the forces that act on a falling body: the 6-degrees of freedom (DOF) and the computation of velocity upon a previous time step. More recently, the former approach has been adopted within the parametric study of a 3D sphere impacting the free surface of water in Yu et al [4], being noted in the recent theoretical exposure in Lu et al [5].…”

Section: Introductionmentioning

confidence: 99%

Water <span aria-describedby="tippy-18">Entry: A Classical Naval Hydrodynamics Problem Enhanced with the Heat and Mass Transfer, and Applied in an Immersion Quenching Simulation

Cukrov,

Landek,

Sato

et al. 2023

Preprint

0

View full text Add to dashboard Cite

The computational model that is able to estimate the temperature distribution inside a solid specimen during the film boiling phase of immersion quenching (water entry) process has been presented in paper, and it is based on the prescribed initial temperatures of the solid specimen and the liquid quenchant. In addition, the turbulence effects have to be considered using the assumed turbulence kinetic energy value, i.e., the “frozen turbulence” approach, that remains constant thorough the simulation. The studied material is nickel alloy, Inconel 600, for which the extensive experimental data is available. The work has been carried out using ANSYS Fluent computational fluid dynamics software and the methods for solution of Stefan problem by Eulerian two fluid VOF model.. A satisfactory agreement between the experimental and the calculated data has been achieved, yielding thereby the computationally obtained data that fits to a great extent to the prescribed error band of ± 10 % during the estimated film boiling phase of the immersion quenching process itself.

show abstract