Department News
Eulerian and Lagrangian Calculations for Multimaterial Flows
Seminar Date
2005-10-31
Author
빈종훈
Date
2005-10-28
Views
1797
1. 제 목 : Eulerian and Lagrangian Calculations for Multimaterial Flows
2. 연 사 : 강명주 조교수
3. 일 시 : 2005년 10월 31일 (월) 오후 4:00 - 5:00
4. 장 소 : 서울대 301동 306호
5. 내 용 :
I will explain the numerical method for modeling multimaterial flows where the domain is decomposed into separate Eulerian and Lagrangian subdomains. The fluid flow which impinges on the solid hull is highly complex. Typically the detonation produces a shock wave and gas bubble which then interacts very strongly with the surrounding fluid to produce the loading on the ship hull. In order to accurately capture such phenomena it is necessary to be able to compute the evolution of the mixed phase flow in the presence of shock waves. A number of approaches have been developed to deal with such problems. Methods based on Lagrangian formulations of fluid mechanics have the advantage that they can naturally track material interfaces provided that no change of phase occurs across the interphase boundary, but these suffer from difficulties caused by strong mesh deformation. Purely Eulerian approaches do not suffer from mesh deformation difficulties and it then becomes possible to apply modem shock capturing techniques. However, Eulerian approaches require the modeling of the interphase boundaries (gas-fluid or fluid-solid boundaries) as "mixed cells" in which fractions of both phases are present in a given Eulerian mesh cell. In many cases the two phases differ markedly in their thermodynamic properties and the error incurred in using such an approach can be severe. We use the Ghost Fluid Method(GFM) to create accurate discretizations across the Eulerian/Lagrangian interface.
6. 약 력 :
Present- Assistant Professor, Department of Mathematical Science, Seoul National University
7. 문 의 : 기계항공공학부 여 재 익 (☏ 880-9334)
2. 연 사 : 강명주 조교수
3. 일 시 : 2005년 10월 31일 (월) 오후 4:00 - 5:00
4. 장 소 : 서울대 301동 306호
5. 내 용 :
I will explain the numerical method for modeling multimaterial flows where the domain is decomposed into separate Eulerian and Lagrangian subdomains. The fluid flow which impinges on the solid hull is highly complex. Typically the detonation produces a shock wave and gas bubble which then interacts very strongly with the surrounding fluid to produce the loading on the ship hull. In order to accurately capture such phenomena it is necessary to be able to compute the evolution of the mixed phase flow in the presence of shock waves. A number of approaches have been developed to deal with such problems. Methods based on Lagrangian formulations of fluid mechanics have the advantage that they can naturally track material interfaces provided that no change of phase occurs across the interphase boundary, but these suffer from difficulties caused by strong mesh deformation. Purely Eulerian approaches do not suffer from mesh deformation difficulties and it then becomes possible to apply modem shock capturing techniques. However, Eulerian approaches require the modeling of the interphase boundaries (gas-fluid or fluid-solid boundaries) as "mixed cells" in which fractions of both phases are present in a given Eulerian mesh cell. In many cases the two phases differ markedly in their thermodynamic properties and the error incurred in using such an approach can be severe. We use the Ghost Fluid Method(GFM) to create accurate discretizations across the Eulerian/Lagrangian interface.
6. 약 력 :
Present- Assistant Professor, Department of Mathematical Science, Seoul National University
7. 문 의 : 기계항공공학부 여 재 익 (☏ 880-9334)
