STAR-CCM+ v7 new feature Overset Mesh

PDT2 안중현 대리

What are Overset Meshes?

A paradigm shift in engineering simulation

– Overset meshes cuts down the entire analysis workflow

– Opens up a range of new applications

• Required when simulating bodies with extreme ranges of motion

• Relevant for Parametric design studies

This is achieved by:

– A background mesh enclosing the whole solution domain

– Separate meshes enclosing each body

– The regions overlap, and flow-field information is passed between them

Industrial Applications: Aerospace

Industrial Applications: Automotive

Industrial Applications: Manufacturing

Industrial Applications: Marine

The Overset Mesh Workflow

1. 두 개 영역을 생성 : Far-field 영역을 포함하는 Background 영역과 Overset body 를 둘러싸고 있는 영역

2. 두 영역은 각각의 분리된 격자를 갖는다. – 각각의 두 영역이 겹치는 cell들은 서로 공유하게 된다.

3. Overset body의 외곽 면은 “Overset Mesh”로 설정하고, 두 영역 사이에 “Overset mesh interface”를 생성한다.

4. Overset body가 배경영역으로 이동함에 따라, 겹치는 구간 (Overlapping zone)이 변하게 된다.

5. 겹치는 구간의 cell을 통하여 두 영역 간에 정보가 이동된다.

Construction of the Overset Mesh

Cells from

background region

Cells from overset

region

Assembled cells

from both regions

Active cells

Passive

cells

Acceptor Cells

Active cells

• Active Cells - 이산화방정식에 의해 계산 • Passive Cells - 계산되지 않음 • Acceptor Cells - overset boundary와 background mesh 사이의 cell 두 격자를 연결

Data Transfer Between the Meshes

Active cells

Passive

cells

Acceptor Cells

Active cells

Acceptor Cells

Demonstration

Overset Mesh Example Demonstration

Demo – Result Animation

현업 적용 사례

S사: 이송장치 해석

S사: Plate 제작 공정 해석

There may be more than one overset boundary, but overset boundaries

can not touch each other

Overset boundaries may exit the domain, but wall boundaries may not

(there must be 4 layers of cells between the wall and the domain

boundary)

Incompatible Models:

– Lagrangian / DEM

– Sliding interfaces

– Windshield models

– Liquid film

– S2S Radiation

– Solid Stress

– Grid Sequencing

STAR-CCM+ v7.06 Limitations