Search the Community

Showing results for tags 'wave reflexion'.

• Search By Tags

Type tags separated by commas.

Forums

• Altair Support Forum
• Welcome to Altair Support Forum
• Installation and Licensing
• Modeling & Visualisation
• Solvers & Optimization
• Multi Body Simulation
• Conceptual design and Industrial design
• Model-Based Development
• Manufacturing Simulation
• CAE Process Automation
• APA - Composites
• APA - CFD & Thermal
• APA - Vehicle Dynamics
• APA - Manufacturing
• APA - Crash and Safety
• APA - Noise, Vibration and Harshness
• APA - System Level Design
• APA - Structural and Fatigue
• APA - Marine
• APA - Optical Design
• Japanユーザーフォーラム
• ユーザーフォーラムへようこそ
• Altair製品の意外な活用例
• インストール / ライセンス / その他
• モデリング（プリプロセッシング）
• シミュレーション技術（ソルバー）
• データ可視化（ポストプロセッシング）
• モデルベース開発
• コンセプト設計と工業デザイン
• 製造シミュレーション
• CAE プロセスの自動化
• エンタープライズソリューション
• データアナリティクス
• 学生向け無償版

Found 1 result

1. How to model an infinite fluid volume, to avoid wave reflexion

Hi, I'm trying to simulate the interraction between a box and waves in the sea. Thus I'm using the material LAW37 (BIPHAS) in order to model the interface between water and air which are modeled in ALE. The problem is that I don't know how to model the boundary conditions on the transverse faces in order to avoid wave reflexions on the wall (to simplify the computation, all DoFs are fixed on the longitudinal faces). I can't use MAT/BOUND (LAW11) because it doesn't work properly with the LAW37. So i'm trying to model these boundary conditions using a material LAW37 to create an "air outlet" and a "water outlet" with the same initial values as air except for : -the liquid bulk modulus C_Liquid = 0.0 - gamma = 0.0 The computation runs well at the beginning and i get a pressure gradient in the fluid volume, so it's okay. But then an error appears : " STOP : NEGATIVE RHO=-0.1322538772563E-09 FOR 3D-ELEMENT ID=3696 ERROR TERMINATION " In the results file I can see that there is a problem with a really big velocity vector on top of the volume in the air part. I think this is linked, but I don't know how to avoid this. Moreover, to model the interface between the box and the water, I use INTER/TYPE18 but I don't know how to set the right value for the StfVal. Using the formula written in the Hyperworks Help i.e. StfVal=(rho * v² * Sel)/GAP , the box is floating in the air, and not in the water. Do you have any suggestion? Thank you very much in advance, Hereby the .rad file ALE_05a_0000.rad
×
×
• Create New...