This article presents a scheme that directly calculates permeability distribution of a preform during the RTM process. The measured filling front locations as well as the corresponding inlet conditions are used in the proposed scheme to calculate the permeability distribution that also takes into account race-tracking phenomenon. The proposed scheme employs a numerical optimization algorithm to minimize a cost function that leads to the permeability field of the preform. Time-step-independent RTM filling algorithm is utilized as a computational kernel to generate the cost function for the subsequent minimization. Numerical development of the proposed scheme is discussed in this article. In addition, the proposed scheme is applied to several test problems involving a variety of spatial permeability distribution of the preform including a situation that involves race-tracking phenomena.
Um MK and Lee WIA study on the mold filling process in resin transfer molding. Polym Eng Sci1991; 31: 765-771.
2.
Chan AW and Hwang STModeling non-isothermal impregnation of fibrous media with reactive polymer resin. Polym Eng Sci1992; 32: 310-318.
3.
Lee HS, Sin HC and Kim SGIterative boundary pressure reflection method for the simulation of injection mold filling. Polym Eng Sci1990; 30: 1513-1522.
4.
Garcia MA, Macosko CW, Subbiah S. and Guceri SIModeling of reactive filling in complex cavities. Int Polym Proc1991; 6: 73-82.
5.
Bruschke MV and Advani SGA finite element/control volume approach to mold filling in anisotropic porous media. Polym Compos1990; 11: 398-405.
6.
Maier RS, Rohaly TF, Advani SG and Fickie KDFast numerical method for isothermal resin transfer mold filling. Int J Numer Meth Eng1996; 39: 1405-1417.
7.
Young WB, Rupel K., Han K., Lee LJ and Liou MJAnalysis of resin injection molding in molds with preplaced fiber mats. II: Numerical simulation and experiments of mold filling. Polym Compos1991; 12: 30-38.
8.
Lin R., Lee LJ and Liou M.Non-isothermal mold filling and curing simulation in thin cavities with preplaced fiber mats. Int Polym Proc1991; 6: 356-369.
9.
Voller VR and Peng S.An algorithm for analysis of polymer filling of molds. Polym Eng Sci1995; 35: 1758-1765.
10.
Boccard A., Lee WI and Springer GSModel for determining the vent locations and the fill time of resin transfer molds. J Compos Mater1995; 29: 306-333.
11.
Voller VR and Chen YFPrediction of filling times of porous cavities. Int J Numer Meth Fluid1996; 23: 661-672.
12.
Chen YF, Stelson KA and Vollert VRPrediction of filling time and vent locations for resin transfer molds. J Compos Mater1997; 31: 1141-1161.
13.
Gebart BRPermeability of unidirectional reinforcements for RTM. J Compos Mater1992; 26: 1100-1133.
14.
Advani SGFlow and rheology in polymer composites manufacturing. Vol. 10, Amsterdam: Elsevier Science, 1994.
15.
Berdichevsky AL and Cai Z.Preform permeability predictions by self-consistent method and finite element simulation. Polym Compos1993; 14: 132-143.
16.
Cai Z. and Berdichevsky ALEstimation of the resin flow permeability of fiber tow preforms using the self-consistent method. Polym Compos1994; 15: 240-246.
17.
James Wang T., Wu CH and James Lee L.In-plane permeability measurement and analysis in liquid composite molding. Polym Compos1994; 15: 278-288.
18.
Ahn SH, Lee WI and Springer GSMeasurement of the three-dimensional permeability of fiber preforms using embedded fiber optic sensors. J Compos Mater1995; 29: 714-733.
19.
Trevino L., Rupel K., Young WB, Liou MJ and Lee LJAnalysis of resin injection molding in molds with preplaced fiber mats. I: Permeability and compressibility measurements. Polym Compos1991; 12: 20-29.
20.
Morren G., Bossuyt S. and Sol H.2D permeability tensor identification of fibrous reinforcements for RTM using an inverse method. Compos Part A-Appl S2008 ; 39: 1530-1536.
21.
Jing L., Xiang F., Zhang C., Liang R. and Wang B.Optimal injection design for resin transfer molding with in situ permeability measurement and process simulation. J Compos Mater2009; 43: 1695-1712.
22.
Weitzenböck JR, Shenoi RA and Wilson PAMeasurement of three-dimensional permeability . Compos Part A - Appl SciManufac1998; 29: 159-169.
23.
Devillard M. , Hsiao K.-T, Gokce A. and Advani SGOn-line characterization of bulk permeability and race-tracking during the filling stage in resin transfer molding process . J Compos Mater2003; 37: 1525-1541.
24.
Pan R., Liang Z., Zhang C. and Wang B.Statistical characterization of fiber permeability for composite manufacturing . Polym Compos2000; 21: 996-1006.
25.
Tortorelli DA, Tiller MM and Dantzig JAOptimal design of non-linear parabolic systems. Part I: Fixed spatial domain with applications to process optimization. Comput Method Appl Mech Eng1994; 113: 141-155.
26.
Baliga BR and Patankar SVA control volume finite-element method for two-dimensional fluid flow and heat transfer. Numer Heat Transfer1983; 6: 245-261.
27.
Fong L. and Lee LJPreforming analysis of thermoformable fiber mats - preforming effects on mold filling. J Reinf Plast Compos1994; 13: 637-663.
