복합격자법을 이용한 수지이동성형의 충전공정에 대한 수치모사

이성재

Korean Journal of Rheology, Vol.9, No.3, 103-110, September, 1997

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복합격자법을 이용한 수지이동성형의 충전공정에 대한 수치모사

Simulation for the Filling Process of Resin Transfer Molding by Incorporating Composite Grids

이성재

초록

고분자 복합재료 제조방법의 하나인 수지이동성형의 충전공정을 모사하기 위한 수치모사 코드를 개발하였다. 수지이동성형의 충전공정 문제를 수학적 공식으로 표현하기 위하여 비등방성 다공질체를 통과하는 유동에 대한 이론을 사용하였다. 과도상태로 진행하는 자유표면의 동적 충전거동을 묘사하기 위하여 수치격자 생성(numerical grid generation)을 포괄하는 경계적합 좌표계(boundary-fitted coordinate systems)의 계산기법을 적용하였다. 이와 아울러 불규칙적인 구조와 다중으로 연결된 금형면의 충전모사에 적합한 복합격자(composite grids)의 개념을 도입하였다. 복합격자들 간의 가상의 경계에 대해서는 검사체적(control volume) 기법을 이용하여 물질보존을 만족시켜 주었다. 임의의 금형 두께와 투과도를 가지는 다수의 금형면이 결합된 두 개의 입구를 지닌 금형을 대상으로 하여 몇 가지 예를 시험해 보았다. 수치모사의 결과 복합격자의 개념을 도입한 수치모사 코드는 수지이동성형의 복잡한 충전공정을 보다 정교하게 묘사하는데 응용될 수 있음을 보여 주었다.

A numerical code to simulate the filling process of resin transfer molding (RTM) for the manufacturing of polymer composite materials was developed. The theory of flow through anisotropic porous media was used for the mathematical formulation of this problem. To describe the dynamic filling patterns of transient free surface, the computational technique of boundary-fitted coordinate systems encompassing numerical grid generation was applied. Also introduced was the approach of composite grids which was suitable for irregular geometries and multiple domains. Control volume scheme was implemented for the mass conservation along the pseudo-boundaries interfacing composite grids. Some examples were tested for the analysis of doublygated mold with multiply-jointed domains including variable gap thickness and permeability. Numerical result showed the applicability of the composite grid approach in achieving accurate modeling of the filling process of resin transfer molding.

Keywords:Resin transfer molding (RlM);mold filling process;numerical simulation;boundary-fitted coordinate systems(BFCS);composite grids

[References]

Ashby MF, Phil. Trans. Roy. Soc. Lond. Seres A, 322, 393 (1987)
Richardson S, J. Fluid Mech., 56, 609 (1972)
White JL, Polym. Eng. Sci., 15, 44 (1975)
Hieber CA, Shen SF, J. Non-Newton. Fluid Mech., 7, 1 (1980)
Yalvac S, Cohen A, Pollard M, Proc. 1st Intern. Conference on Transport Phenomena in Processing, Honolulu, HI (1992)
Wang VW, Hieber CA, Wang KK, J. Polym. Sci., 7, 21 (1986)
Tadmor Z, Broyer E, Gutfinger C, Polym. Eng. Sci., 14, 660 (1974)
Trafford DL, M.S. Thesis, Univ. of Delaware, Newark, DE (1987)
Coulter JP, Guceri SI, ASTM STP1044, 14 (1989)
Friedrichs B, Ph.D. Thesis, Univ. of Delaware, Newark, DE (1993)
Lee SJ, Guceri SI, Proc. 11th Conference of Polymer Processing Society, 151, Seoul, Korea (1995)
Guceri SI, "Fundamentals of Computer Modeling for Polymer Processing," ed. by C.L. Tucker, Hanser Publishers, Munich, ch. 5 (1989)
Subbiah S, Trafford DL, Gticeri SI, Int. J. Heat Mass Transf., 32, 415 (1989)
Warsi ZUA, AIAA J., 19, 240 (1981)
Thompson JF, "Numerical Grid Generation in Computational Fluid Dynamics," ed. by J. Hauser and C. Taylor, Pineridge, Swansea, p. 271 (1986)
Greenberg MD, "Advanced Engineering Mathematics," Prentice-Hall Inc., Englewood Cliffs, NJ, p. 56 (1988)
Aoyagi H, Center for Composite Materials Report, CCM 92-26, Univ. of Delaware, Newark, DE (1992)
Aoyagi H, Uenoyama M, Guceri SI, Int. Polym. Process., 7(1), 71 (1992)
Fisa B, Rahmani M, Polym. Eng. Sci., 31, 1330 (1991)
Mavridis H, Hrymak AN, Vlachopoulos J, AIChE J., 34, 403 (1988)
Lee HS, Sin HC, Kim SG, Polym. Eng. Sci., 30, 1513 (1990)

[1] Ashby MF, Phil. Trans. Roy. Soc. Lond. Seres A, 322, 393 (1987)

[2] Richardson S, J. Fluid Mech., 56, 609 (1972)

[3] White JL, Polym. Eng. Sci., 15, 44 (1975)

[4] Hieber CA, Shen SF, J. Non-Newton. Fluid Mech., 7, 1 (1980)

[5] Yalvac S, Cohen A, Pollard M, Proc. 1st Intern. Conference on Transport Phenomena in Processing, Honolulu, HI (1992)

[6] Wang VW, Hieber CA, Wang KK, J. Polym. Sci., 7, 21 (1986)

[7] Tadmor Z, Broyer E, Gutfinger C, Polym. Eng. Sci., 14, 660 (1974)

[8] Trafford DL, M.S. Thesis, Univ. of Delaware, Newark, DE (1987)

[9] Coulter JP, Guceri SI, ASTM STP1044, 14 (1989)

[10] Friedrichs B, Ph.D. Thesis, Univ. of Delaware, Newark, DE (1993)

[11] Lee SJ, Guceri SI, Proc. 11th Conference of Polymer Processing Society, 151, Seoul, Korea (1995)

[12] Guceri SI, "Fundamentals of Computer Modeling for Polymer Processing," ed. by C.L. Tucker, Hanser Publishers, Munich, ch. 5 (1989)

[13] Subbiah S, Trafford DL, Gticeri SI, Int. J. Heat Mass Transf., 32, 415 (1989)

[14] Warsi ZUA, AIAA J., 19, 240 (1981)

[15] Thompson JF, "Numerical Grid Generation in Computational Fluid Dynamics," ed. by J. Hauser and C. Taylor, Pineridge, Swansea, p. 271 (1986)

[16] Greenberg MD, "Advanced Engineering Mathematics," Prentice-Hall Inc., Englewood Cliffs, NJ, p. 56 (1988)

[17] Aoyagi H, Center for Composite Materials Report, CCM 92-26, Univ. of Delaware, Newark, DE (1992)

[18] Aoyagi H, Uenoyama M, Guceri SI, Int. Polym. Process., 7(1), 71 (1992)

[19] Fisa B, Rahmani M, Polym. Eng. Sci., 31, 1330 (1991)

[20] Mavridis H, Hrymak AN, Vlachopoulos J, AIChE J., 34, 403 (1988)

[21] Lee HS, Sin HC, Kim SG, Polym. Eng. Sci., 30, 1513 (1990)