用户名: 密码: 验证码:
三维塑料注射成形及结晶过程数值模拟关键技术研究
详细信息    本馆镜像全文|  推荐本文 |  |   获取CNKI官网全文
摘要
注射成形是塑料制品最重要的成形方式之一,提高塑料制品质量和工艺成形性的一个有效方法是采用数值模拟技术,对成形过程进行准确预测,为优化产品设计和优选工艺参数提供指导。由于基于Hele-Shaw假设的表面模型数值模拟,不能满足日益复杂和大型制品的精确模拟要求,因此迫切需要采用三维实体模拟技术。本文对塑料注射成形及结晶过程的三维有限元模拟进行了比较系统的研究,并编制了数值模拟软件,研究内容主要包括以下几个方面:
     (1)在充模过程的模拟中,针对流动数值模拟中的速度与压力的插值空间不协调导致的数值振荡问题,分别建立了基于GLS(Galerkin least-squares)法的速度、压力任意插值的集成格式稳定有限元计算模型和基于PSPG(Pressure-Stabilizing /Petrov-Galerkin)法的速度、压力同次插值的分离格式稳定有限元计算模型。而对于能量场方程中对流占优和小扩散系数造成的数值不稳定问题,则建立了基于GLS/GGLS(Galerkin gradient least-squares)法的稳定有限元计算模型。此外,扩展的三维FAN法用于充模过程中的流动前沿跟踪。
     (2)在充模后的保压过程模拟中,熔体与凝固层相互作用,作为一个整体受保压压力的作用,建立了三维可压缩熔体流动和粘弹性凝固层变形的固熔两相耦合计算模型;在冷却过程模拟中,制品在型腔内受约束变形,建立了三维粘弹性有限元计算模型;在翘曲模拟中,建立了三维弹性变形的有限元计算模型,由此完成了三维注射成形充模后模拟的有限元计算模型的建立。
     (3)根据所建立的充模过程计算模型,对注射成形的充模过程进行了模拟,研究了流动前沿、喷泉效应、跑道效应和充模过程中的温度场;采用不同的网格密度考察了本文算法的精度对网格粗细程度的依赖性;分析了充模工艺参数对充模过程的影响;比较了不可压缩与可压缩假设的熔体充模过程的差异;通过对具有一定形状复杂程度的制品的模拟,表明所建立的充模计算模型具有很好的精度、稳定性和实用性。
     (4)在所建立的保压、冷却和翘曲计算模型基础上,研究了工艺参数对制品残余应力、收缩和翘曲的影响;在保压、冷却模拟中,分别采用弹性模型和粘弹性模型计算了凝固层的热残余应力及模内变形。
     (5)基于剪切应力能提高等效熔点的理论,建立了剪切诱导时间指数和剪切诱导结晶的计算模型,给出了结晶对注射成形过程中熔体粘度的影响模型及考虑结晶放热的注射成形能量场控制方程,模拟研究了成形工艺参数对结晶及结晶对注射成形过程的影响。
     此外,在数值算例中,本文的模拟结果与实验结果及国外著名的注射成形模拟软件Moldflow的模拟结果进行了对比,吻合得比较好,验证了本文提出的计算模型的精确性与合理性,表明所开发三维实体模拟软件可为提高制品质量和注射成形工艺提供指导。
Injection molding is one of the most important manufacturing processes for plastic products. The quality and performance of injection molded parts depend not only on the material, but also on how the material is processed. With computer-aided engineering(CAE) tools, better understanding of parts during process can be achieved to help engineers to improve part design and optimize processing conditions. However the traditional CAE techniques for the simulation of injection molding, called by the middle-plane technique and dual domain technique based on Hele-Shaw approximation, pose inherent limitations when the part has complex geometrical configuration or thick walls. Three dimensional (3D) simulation based on the solid element can give deeper insight into molding process by providing more detailed information than traditional techniques.
     Injection molding process and crystallization of semicrystalline polymers were modeled systematically using the finite element method, and programs were developed to simulate the injection molding and crystallization. The following work was included:
     (1) The GLS(Galerkin/Least-squares) method is employed to prevent the potential numerical instabilities by adding to the weighting functions with their derivatives, resulting in the integrated symmetric and stabilized finite element formulations using arbitrary interpolation functions for velocity and pressure. The similar segregated stabilized finite element formulation using equal-order interpolation functions for velocity and pressure can be obtained based on the PSPG(Pressure-Stabilizing/ Petrov-Galerkin) method. Because of the convection term and small heat conduction coefficient in the governing equation of energy, spurious oscillation associated with the classic Galerkin finite element method is induced. And GLS/GGLS(Galerkin gradient least-squares) methods are applied to avoid these oscillations. The expanded 3D FAN scheme is applied to capture the advanced melt front.
     (2) During the packing stage, the polymer melt solidifies partly with the decrease of temperature. Molten and solid polymers interact, and act as a whole entity by the packing pressure. A 3D two-phase coupling model combining the flow of compressible melt with the deflection of viscoelastic solid is established. During the cooling stage, a 3D viscoelastic constitutive model is presented to show the evolvement of residual thermal stresses while part deflects confined to the mold cavity. To simulate the warpage of plastic parts ejected from cavity, a 3D elastic constitutive model is given. And so far, the complete 3D approximation of postfilling is made.
     (3) In the numerical simulation of filling stage, advanced melt front, fountain flow, effect of runway and temperature field of the part were studied. Fine and coarse finite element mesh were used to show the stability and accuracy of the proposed algorithms. Different processing conditions were adopted to investigate the effect of processing parameters on the filling stage. Results were compared to show that the hypothesis of compressible flow leads to more reasonable injection pressure than incompressible flow. Examples showed that the proposed algorithms could be accurate and practical for parts with complex geometry.
     (4) Numerical simulations were carried out to study the effect of processing parameters on the residual thermal stresses and shrinkage of parts. The elastic and viscoelastic constitutive models were adopted seperately to computer residual thermal stresses and deflection for the solid during the packing and cooling stages.
     (5) The stress-induced induction time index and crystallization models for semicrystalline plastics were proposed based on the theory that stress-induced orientation of polymer chains increases the equilibrium melting temperature. The effect of crystallinity on viscosity of the polymer melt and temperature due to latent heat of fusion is described. To investigate the effect of processing parameters on the crystallinity, the injection molding process of semicrystalline plastics was simulated under different processing conditions.
     In addition, lots of numerical examples showed the results of presented 3D approaches developed herein were in good agreement with the experimental results or results of the well-known commercial software Moldflow. It was suggested that the presented 3D approaches could present accurate, stable and practical results.
引文
[1]李德群,李阳,陈立亮等.材料成形过程模拟技术及其应用.中国机械工程, 2006, 17(19):2005~2009
    [2]李德群,肖祥芷.模具CAD/CAE/CAM发展概况及趋势.模具工业, 2005, 7:9~12
    [3]李德群.国内外注塑模CAD/CAE/CAM发展概况.模具工业, 1994, (9):47~53
    [4]李德群,陈兴.注塑模CAD/CAE/CAM技术的发展和应用.塑料科技, 1992, 2(1): 28~31
    [5]卢义强.注塑冷却过程模拟及制品的翘曲分析:[博士学位论文].武汉:华中科技大学图书馆, 1994.
    [6] Deng Y. M., Lam Y. C., Tor S. B. et al. A CAD-CAE Integrated Injection Molding Design System. Engineering with Computers, 2002, 18:80~92
    [7] Chun D. H.. Cavity filling analyses of injection molding simulation: bubble and weld line formation. Journal of Materials Processing Technology, 1999, 89~90: 177~181
    [8] Liu T. J., Yu Y. W., Hsu C. L. et al. A hybrid 3D/2D finite element technique for polymer processing operations. Polymer Engineering and Science, 1999, 39(1): 44~54
    [9] Kwong C. K., Mok S. L., Lau W. S.. Review of research in the determination of process parameters for plastic injection molding. Advances in Polymer Technology, 1999, 18(3):225~236
    [10] Zachert Jurgen, Michaeli Walter. Simulation and analysis of three-dimensional polymer flow in injection moulding. Journal of Reinforced Plastics and Composites, 1998, 17(10):955~962
    [11] Stevenson J. F., Galskoy A., Wang K. K. et al. Injection Molding in Disk-ShapedCavities. Polymer Engineering and Science, 1977, 17(9):706~711
    [12] Bentsen R. G., Donohue D. A. T.. Dynamic Programming model of the Cyclic Steam Injection Process. Journal of Petroleum Technology, 1969, 21(12):1582~1596
    [13] Loveless H. S., Williams M. C.. Physical Properties of Some Injection Molder Thermoplastic of Various Glass Contents. Polymer Engineering and Science, 1970, 10(3):139~147
    [14] Wang K. K.. System Approach to Injection Molding Process. Polymer-Plastics Technology and Engineering, 1980, 14(1):75~93
    [15] Toor H. L., Ballman R. L., Cooper L.. Prediction mold flow by electronic computer. Modern Plastics, 1960, 39(1):117~209
    [16] Harry D. H., Parrott R. G.. Numerical simulation of injection mold filling. Polymer Engineering and Science, 1970, 10(4):209~214
    [17] Williams G., Lord H. A.. Mold-filling studies for the injection molding of thermoplastic materials, part I: the flow of plastic materials in hot- and cold-walled circular channels. Polymer Engineering and Science, 1975, 15(8):553~559
    [18] Lord H. A., Williams G.. Mold-filling studies for the injection molding of thermoplastic materials, part II: the transient flow of plastic materials in the cavities of injection molding dies. Polymer Engineering and Science, 1975, 15(9):596~603
    [19] Broyer E., Gutfinger C., Tadmor Z.. Theoretical model for the cavity filling process in injection molding. Transactions of the Society of Rheology, 1975, 19(3):423~444
    [20] Hieber C. A., Shen S. F.. Flow analysis of the non-isothermal two-dimensional filling process in injection molding. Israel Journal of Technology, 1978, 16(5-6): 248~254
    [21] Hieber C. A., Socha L. S., Shen S. F. et al. Filling thin cavities of variable gap thickness: a numerical and experimental investigation. Polymer Engineering and Science, 1983, 23(1):20~26
    [22] Wang K. K., Hieber C. A.. Viscosity-based simulation of the injection molding process. Interdisciplinary Issues in Materials Processing and Manufacturing, 1987, (2):645~660
    [23] Hieber C. A., Shen S. F.. Finite-element/finite-difference simulation of the injection-molding filling process. Journal of Non-Newtonian Fluid Mechanics, 1980, 7(1):1~32
    [24] Chen B. S., Liu W. H.. Numerical simulation and experimental investigation of injection mold filling with melt solidification. Polymer Engineering and Science, 1989, 29(15):1039~1050
    [25] Reinelt D. A.. Interface conditions for two-phase displacement in Hele-Shaw cells. Journal of Fluid Mechanics, 1987, 183:219~234
    [26]吴映辉.塑料注射成型充模过程流动模拟的边界元方法:[博士学位论文].成都:成都科技大学, 1992.
    [27] Fernandes R. C., Fernandes R. C., Semial R. et al.. Hydrodynamic model for gas-liquid slug flow in vertical tubes. AIChE Journal, 1983, 29(6):981~989
    [28] Matsuoka Takaaki, Takahashi Hideroh, Kamigaito Osami. Flow analysis in injection molding. Journal of the Japan Society of Powder and Powder Metallurgy, 1987, 34(9):387~391
    [29] Chang Rong-Yeu, Yang Wen-Hsien. Numerical simulation of mold filling in injection molding using a three-dimensional finite volume approach. International Journal for Numerical Methods in Fluids, 2001, 37:125~148
    [30] Kim Sang-Woo, Turng Lih-Sheng. Three-dimensional numerical simulation of injection molding filling of optical lens and multiscale geometry using finite element method. Polymer Engineering and Science, 2006, 46(9):1263~1274
    [31] Hetu J. -F., Gao D. M., Garcia-Rejon A. et al. 3D finite element method for the simulation of the filling stage in injection molding. Polymer Engineering and Science, 1998, 38(2):223~236
    [32] Pichelin E., Coupez T.. A Taylor discontinuous Galerkin method for the thermal solution in 3D mold filling. Computer Methods in Applied Mechanics and Engineering, 1999, 178:153~169
    [33] Pichelin E., Coupez T.. Finite element solution of the 3D mold filling problem for viscous incompressible fluid. Computer Methods in Applied Mechanics and Engineering, 1998, 163:359~371
    [34] Greener J.. General consequences of the packing phase in injection molding. Polymer Engineering and Science, 1986, 26(12):888~892
    [35] Spencer R. S., Gilmore G. D.. Some flow phenomena in the injection molding of polystyrene. Journal of Colloid Science, 1951, 6(2):118~132
    [36] Kamal M. R., Kenig S.. The injection molding of thermoplastics part I: theoretical model. Polymer Engineering and Science, 1972, 12(4):294~301
    [37] Kamal M. R., Kenig S.. The injection molding of thermoplastics part II: experimental test of the model. Polymer Engineering and Science, 1972, 12(4): 302~308
    [38] Kamal M. R., Kuo Y., Doan P. H.. The injection molding behavior of thermoplastics in thin rectangular cavities. Polymer Engineering and Science, 1975, 15(12): 863~868
    [39] Kamal M. R., Victor Tan. Orientation in injection molded polystyrene. Polymer Engineering and Science, 1979, 19(8):558~563
    [40] Chung T. S.. Pressure bulid-up during the packing stage of injection molding. Polymer Engineering and Science, 1985, 25(12): 772~777
    [41] Chung T. S., Ryan M. E.. Analysis of the packing stage in injection molding. Polymer Engineering and Science, 1981, 21(5):271~275
    [42] Chiang H. H., Hieber C. A., Wang K. K.. A unified simulation of the filling and post-filling stages in injection molding, part I: formulation. Polymer Engineering and Science, 1991, 31(2):116~124
    [43] Chiang H. H., Hieber C. A., Wang K. K.. A unified simulation of the filling and post-filling stages in injection molding, part II: experimental verification. Polymer Engineering and Science, 1991, 31(2):125~139
    [44] Lee S. C., Yang D. Y., Ko J. et al. Effect of compressibility on flow field and fiber orientation during the filling stage of injection molding. Journal of Material Processing Technology, 1997, 70:83~92
    [45] Han Kyeong-Hee, Im Yong-Taek. Compressible flow analysis of filling and postfilling in injection molding with phase-change effect. Composite Structures, 1997, 38(1-4):179~190
    [46] Bushko W. C., Stokes V. K.. Solidification of thermoviscoelastic melts. Part I: Formulation of model problem. Polymer Engineering and Science, 1995, 35(4): 351~364
    [47] Bushko W. C., Stokes V. K.. Solidification of thermoviscoelastic melts. Part II: Effects of processing conditions on shrinkage and residual stresses. Polymer Engineering and Science, 1995, 35(4):365~383
    [48] Bushko W. C., Stokes V. K.. Solidification of thermoviscoelastic melts. Part 3: Effects of mold surface temperature differences on warpage and residual stresses. Polymer Engineering and Science, 1996, 36(3):322~335
    [49] Bushko W. C., Stokes V. K.. Solidification of thermoviscoelastic melts. Part 4: Effects of boundary conditions on shrinkage and residual stresses. Polymer Engineering and Science, 1996, 36(5):658~675
    [50] Titomanlio G., Jansen K. M. B.. In-mold shrinkage and stress prediction in injection molding. Polymer Engineering and Science, 1996, 36(15):2041~2049
    [51] Jansen K. M. B., Van Dijk D. J., Husselman M. H.. Effect of processing conditions on shrinkage in injection molding. Polymer Engineering and Science, 1998, 38(5):838~846
    [52] Jansen K. M. B., Titomanlio G.. Effect of pressure history on shrinkage and residualstress-injection molding with constrained shrinkage. Polymer Engineering and Science, 1996, 36(15):2029~2040
    [53] Zoetelief W. F., Douven L. F. A., Ingen Housz A. J.. Residual thermal stresses in injection molded products. Polymer engineering and science, 1996, 36(14):1886~1896
    [54] Zheng R., Kennedy P., Phan-Thien N. et al. Thermoviscoelastic simulation of thermally and pressure-induced stresses in injection moulding for the prediction of shrinkage and warpage for fibre-reinforced thermoplastics. Journal of Non-Newtonian Fluid Mechanics, 1999, 84:159~190
    [55] Kabanemi K., Crochet M. J.. Thermoviscoelastic calculation of thermoviscoelastic stresses in injection-molded parts. International Polymer Processing, 1992, 7:60~70
    [56] Kabanemi K. K., Vaillancourt H., Wang H. et al. Residual stresses, shrinkage, and warpage of complex injection molded products: numerical simulation and experimental validation. Polymer Engineering and Science, 1998, 38(1):21~37
    [57] Boitout F., Agassant J. F., Vincent M.. Elastic calculation of residual stresses in injection molding. International Polymer Processing, 1995, 10:237~242
    [58] Denizart O., Vincent M., Agassant J. F.. Thermal stresses and strains in injection moulding: experiments and computations. Journal of Materials Science, 1995, 30(2):552~560
    [59] Kamal M. R., Lai-Fook R. A., Hernandez-Aguilar J. R.. Residual thermal stresses in injection moldings of thermoplastics: a theoretical and experimental study. Polymer Engineering and science, 2002, 42(5):1098~1114
    [60] Dutta N. K., Edward G. H.. Generic relaxation spectra of solid polymers. I. development of spectral distribution model and its application to stress relaxation of polypropylene. Journal of Applied Polymer Science, 1997, 66:1101~1115
    [61] Matsuoka Takaaki, Takabatake Jun-Ichi, Koiwai A. et al. Integrated simulation to predict warpage of injection molded parts. Polymer Engineering and Science, 1991,31(14):1043~1050
    [62] Kikuchi H., Koyama K.. Material anisotropy and warpage of nylon 66 composites. Polymer Engineering and Science, 1994, 34(18):1411~1418
    [63] Chang R. Y., Tsaur B. D.. Experimental and theoretical studies of shrinkage, warpage, and sink marks of crystalline polymer injection molded parts. Polymer Engineering and Science, 1995, 35(15):1222~1230
    [64] Delaunay D., Le Bot P., Fulchiron R. et al. Nature of contact between polymer and mold in injection molding. Part II: influence of mold deflection on pressure history and shrinkage. Polymer Engineering and Science, 2000, 40(7):1692~1700
    [65] Choi Du-Soon, Im Yong-Taek. Prediction of shrinkage and warpage in consideration of residual stress in integrated simulation of injection molding. Composite Structures, 1999, 47:655~665
    [66] Fan Bingfeng, Kazmer David O., Bushko Wit C. et al. Warpage prediction of optical media. Journal of Polymer Science: Part B: Polymer Physics, 2003, 41:859~872
    [67] Viana J. C., Cunha A. M., Billon N.. The thermomechanical environment and the microstructure of an injection moulded polypropylene copolymer. Polymer, 2002, 43(15):4185~4196
    [68] Mendoza R., Regnier G., Seiler W. et al. Spatial distribution of molecular orientation in injection molded iPP: influence of processing conditions. Polymer, 2003, 44(11):3363~3373
    [69] Kantz M. R., Newman J. R., Stigale F. H.. The skin-core morphology and structure–property relationships in injection–moulded polypropylene. Journal of Applied Polymer Science, 1972, 16:1249~1260
    [70] Fujiyama M., Wakino T., Kavasaki Y.. Structure of skin layer in injection-molded polypropylene. Journal of Applied Polymer Science, 1988, 35(1):29~49
    [71] Hieber C. A.. Modeling/Simulation the injection molding of isotactic polypropylene.Polymer Engineering and Science, 2002, 42(7):1387~1409
    [72] Guo JianXin, Narh Kwabena A.. Computer simulation of stress-induced crystallization in injection molded thermoplastics. Polymer Engineering and Science, 2001, 41(11):1996~2012
    [73] Guo Jianxin, Narh Kwabena A.. Simplified model of stress-induced crystallization kinetics of polymers. Advances in Polymer Technology, 2002, 21(3):214~222
    [74] Guo X., Isayev A. I., Guo L.. Crystallinity and microstructure in injection moldings of isotactic polypropylenes. Part 1: a new approach to modeling and model parameters. Polymer Engineering and Science, 1999, 39(10):2096~2114
    [75] Guo X., Isayev A. I., Demiray M.. Crystallinity and microstructure in injection moldings of isotactic polypropylenes. Part 1: a new approach to modeling and model parameters. Polymer Engineering and Science, 1999, 39(11):2132~2149
    [76] Kim Kyuk Hyun, Isayev A. I., Kwon Keehae. Flow-induced crystallization in the injection molding of polymers: a thermodynamic approach. Journal of Applied Polymer Science, 2005, 95:502~523
    [77] Kim Kyuk Hyun, Isayev Avraam I., Kwon Keehae. Crystallization Kinetics for simulation of processing of various polyesters. Journal of Applied Polymer Science, 2006, 102:2847~2855
    [78] Banik K., Mennig G.. Process-induced long-term deformation behavior of semicrystalline PBT. Polymer Engineering and Science, 2006, 46(7):882~888
    [79] Kwon Keehae, Isayev A. I., Kim K. H. et al. Theoretical and experimental studies of anisotropic shrinkage in injection moldings of semicrystalline polymers. Polymer Engineering and Science, 2006, 46(6):712~728
    [80] Kwon Keehae, Isayev A. I., Kim K. H.. Theoretical and experimental studies of anisotropic shrinkage in injection moldings of various polyesters. Journal of Applied Polymer Science, 2006, 102:3526~3544
    [81] Zhong Ganji, Li Zhongming. Injection molding-induced morphology ofthermoplastic polymer blends. Polymer Engineering and Science, 2005, 45(12):1655~1665
    [82] Murthy N. Sanjeeva, Kagan Val A., Robert G. Bray. Effect of melt temperature and skin-core morphology on the mechanical performance of Nylon 6. Polymer Engineering and Science, 2002, 42(5):940~950
    [83] Pantani R., Coccorullo I., Speranza V. et al. Modeling of morphology evolution in the injection molding process of thermoplastic polymers. Progress in Polymer Science, 2005, 30:1185~1222
    [84]李德群,陈兴,张宜生等.注射模软件的三个发展阶段.模具工业, 1998, 208(6): 3~6
    [85] Kwon T. H., Weeks P. A.. Expert system aid for intelligent molding cooling system design. Computers in Engineering, 1988, 281~286
    [86] Chin K. S., Wang T. N.. An expert system for injection mold cost estimation. Advances in Polymer Technology, 1995, 14(4):303~314
    [87]周华民,李德群.塑料注射成型CAE系统的智能化研究.机械科学与技术, 2004, 23(12):1463~1465
    [88]周华民,李德群.基于成形模拟的注塑件熔接缝确定与评价.中国机械工程, 2004, 15(21):1962~1966
    [89]周华民,李德群.基于型腔表面模型的塑料注射成形的充填保压模拟.中国机械工程, 2002, 13(16):1382~1384
    [90]周华民,李德群.基于Web的远程塑料注射成型CAE系统.机械科学与技术, 2002, 21(5):829~832
    [91]周华民,李德群.面向虚拟制造的塑料注射成形CAE模拟.机械工程学报, 2002, 38(7): 23~27
    [92]周华民,李德群,燕立唐等.集成环境下的智能化塑料注射成型CAE分析.华中科技大学学报, 2002, 30(3):37~39
    [93]周华民,燕立唐,黄棱等.塑料材料的流变实验与流变参数拟合.中国塑料,2001, 15(11):49~52
    [94]周华民,张宜生,李德群.基于表面模型的注射成型充填模拟.自然科学进展, 2001, 11(3):288~292
    [95]周华民,张宜生,李德群.基于三维表面模型的注射成型充填模拟(英文).应用基础与工程科学学报, 2001, 9(1):52~59
    [96]周华民,李德群,张宜生.实用化塑料注射模CAD系统.中国塑料, 1999, 13(1):75~79
    [97]赵朋,周华民,严波等.塑料注射成型中注射压力和熔体温度的快速预测.中国塑料, 2007, 21(9):53~56
    [98]奚国栋,周华民,李德群.注塑制品残余应力数值模拟的研究.中国机械工程, 2007, 18(9):1112~1116
    [99]冯伟,周华民,马建华等.塑料注射缺陷修正的模糊建模方法.中国机械工程, 2007, 18(4):487~491
    [100]崔树标,周华民,李德群.注射模冷却过程数值模拟研究.模具工业, 2007, 33(10):1~6
    [101]奚国栋,周华民,李德群.注塑工艺参数对制品残余应力和收缩的影响.化工学报, 2007, 58(1):248~254
    [102]奚国栋,刘芬,周华民等.注射成型残余应力的数值模拟.华中科技大学学报, 2007, 35(1):106~109
    [103]奚国栋,周华民,李德群.注射过程中残余应力演变的模拟与分析.中国塑料, 2006, 20(4):68~74
    [104]崔树标,周华民,李德群.注塑模冷却过程模拟关键算法研究.中国塑料, 2005, 19(4):95~99
    [105]崔树标,周华民,李德群.注塑模冷却分析中特殊冷却结构的处理.模具技术, 2005, (2):3~5
    [106]李德群,周华民.基于表面模型的智能化塑料注射成型模拟.应用科学学报, 2005, 23(1):16~19
    [107]成学文,李德群,周华民等.基于哈希表的STL面片冗余顶点快速滤除算法.华中科技大学学报, 2004, 32(6):69~71
    [108]李德群,周华民.塑料注射成形过程仿真软件的开发和应用.中国机械工程, 2002, 13(22):1894~1896
    [109]庄礼贤,尹协远,马晖扬.流体力学.合肥:中国科学技术大学出版社, 1991. 92~100
    [110]张涵信,沈孟育.计算流体力学—差分方法的原理和应用.北京:国防工业出版社, 2003. 1~4
    [111]杨根.流体力学有限元.哈尔滨:哈尔滨工程大学出版社, 1995. 179~181
    [112] Babuska I.. Error bounds for finite element method. Numer. Math., 1971, 16:322~333
    [113] Brezzi F.. On the existence, uniqueness and approximation of saddle-point problems arising from Lagrange multipliers. RAIRO Ser. Rouge Anal. Numer., 1979, R-2:129~151
    [114] Mittal S.. On the performance of high aspect ratio elements for incompressible flows. Computer methods in applied mechanics and engineering, 2000, 188:269~287
    [115] Brooks A. N., Hughes T. J. R.. Streamline upwind/Petrov-Galerkin formulations for convection dominated flows with particular emphasis on the incompressible Navier-Stokes equations. Computer Methods in Applied Mechanics and Engineering, 1982, 32:199~259
    [116] Tezduyar T. E., Mittal S., Ray S. E. et al. Incompressible flow computations with stabilized bilinear and linear equal-order-interpolation velocity-pressure elements. Computer Methods in Applied Mechanics and Engineering, 1992, 95:221~242
    [117] Tezduyar T. E.. Computation of moving boundaries and interfaces and stabilization parameters. International Journal for Numerical Methods in Fluids, 2003, 43:555~575
    [118] Franca L. P., Carmo Dutra Do. The Galerkin gradient least-squares method. Computer Methods in Applied Mechanics and Engineering, 1989, 74:41~54
    [119] Harari I., Hughes T. J. R.. Finite element methods for the Helmholtz equation in an exterior domain: model problems. Computer Methods in Applied Mechanics and Engineering, 1991, 87:59~96
    [120] Harari I., Grosh K., Hughes T. J. R. et al. Recent developments in finite element methods for structural acoustics. Archives of Computational Methods in Engineering, 1996, 3:131~309
    [121] Harari I., Hughes T. J. R.. Stabilized finite element methods for steady advection-diffusion with production. Computer Methods in Applied Mechanics and Engineering, 1994, 115:165~191
    [122] Valentin F. G. C., Franca L. P.. Combining stabilized finite element methods. Computer Methods in Applied Mechanics and Engineering, 1995, 14(3): 285~300
    [123] Harari I., Haham S.. Improved finite element methods for elastic waves. Computer Methods in Applied Mechanics and Engineering, 1998, 166:143~164
    [124] Ilinca F., Hetu J. -F.. Galerkin gradient least-squares formulations for transient conduction heat transfer. Computer Methods in Applied Mechanics and Engineering, 2002, 191:3073~3097
    [125] Hughes T. J. R., Franca L. P., Balestra M.. A new finite element formulation for computational fluid dynamics: V. Circumventing the Babuska-Brezzi condition: A stable Petrov-Galerkin formulation of the Stokes problem accommodating equal-order interpolations. Computer Methods in Applied Mechanics and Engineering, 1986, 59:85~99
    [126] Hughes T. J. R., Franca L. P.. A new finite element formulation for computational fluid dynamics: VI. The Stokes problem with various well-posed boundary conditions: symmetric formulations that converge for all velocity/pressure spaces. Computer Methods in Applied Mechanics and Engineering, 1987, 65:85~96
    [127] Hughes T. J. R., Franca L. P., Hulbert G. M.. A new finite element formulation for computational fluid dynamics: VII, The Galerkin-least-squares method for advective-diffusive equations. Computer Methods in Applied Mechanics and Engineering, 1989, 73:173~189
    [128] Zhou Huamin, Li Dequn. Modelling and prediction of weld line location and properties based on injection moulding simulation. International Journal of Materials and Product Technology, 2004, 21(6):526~538
    [129]徐树方.矩阵计算的理论与方法.北京:北京大学出版社, 2001. 162~164
    [130]陶文铨.计算传热学的近代进展.北京:科学出版社, 2000. 297
    [131]金巍巍,陶文铨,何雅玲.代数方程求解方法收敛速度比较及对算法健壮性的影响.西安交通大学学报, 2005, 39(9):966~970
    [132]金巍巍,孙东亮,陶文铨等. Krylov子空间法在SIMPLER算法中的求解性能分析.工程热物理学报, 2007, 28(3):478~480
    [133] Zhang Shao-Liang. GPBi-CG: generalized product-type methods based on Bi-CG for solving nonsymmetric linear systems. SIAM J. Sci. Comput., 1997, 18(2): 537~551
    [134] Tezduyar T. E., Sathe S.. Enhanced-discretization successive update method (EDSUM). International Journal for Numerical Methods in Fluids, 2005, 47:633~654
    [135] Chan T. W., Isayev A. I.. Quiescent polymer crystallization: modeling and measurements. Polymer Engineering and Science, 1994, 34:461~471
    [136] Hammami A., Spruiell J.. Quiescent non-isothermal crystallization kinetics of isotactic polypropylenes. Polymer Engineering and Science, 1995, 35:797~804
    [137] Avrami M.. Granulation, phase change and microstructure: kinetics of phase change. Journal of Chemistry and Physics, 1941, 9:177~184
    [138] Godovsky Y. K., Slonimsky G. L.. Kinetics of polymer crystallization from the melt. Journal of Applied Polymer Science, 1974, 12:1053~1080
    [139] Nakamura K., Watanabe T., Katayama K. et al. Some aspects of non-isothermal crystallization of polymers. I. Relationship between crystallization temperature, crystallinity, and cooling conditions. Journal of Applied Polymer Science, 1972, 16:1077~1091
    [140] Nakamura K., Katayama K., Amano T.. Some aspects of nonisothermal crystallization of polymers.Ⅱ. Consideration of the isokinetic condition. Journal of Applied Polymer Science, 1973, 17:1031~1041
    [141] Hoffman J. D., Lauritzen J. I.. Crystallization of bulk polymers with chain folding: theory of growth of lamellar spherulites. J. Res. Natl. Bur. Stand., 1961, 65A:297~ 336
    [142] Sifleet W. L., Dinos N., Collier J. R.. Unsteady-state heat transfer in a crystallizing polymer. Polymer Engineering and Science, 1973, 13:10~16
    [143] Patel R. M., Spruiell J. E.. Crystallization kinetics during polymer processing- analysis of available approaches for process modeling. Polymer Engineering and Science, 1991, 31:730~738
    [144] Coccorullo I., Pantani R., Titomanlio G.. Crystallization kinetics and solidified structure in iPP under high cooling rates, Polymer, 2003, 44(1):307~318
    [145] Titomanlio G., Speranza V., Brucato V.. On the simulation of thermoplastic injection molding process. Part 2. Relevance of interaction between flow and crystallisation. Int. Polym. Proc., 1997, 12(1):45~53
    [146] Doufas A. K., McHugh A. J., Miller C. et al. Simulation of melt spinning including flow-induced crystallization: Part II. Quantitative comparisons with industrial spinline data. Journal of Non-Newtonian Fluid Mechanics, 2000, 92(1):81~103
    [147] Tanner R.. A suspension model for low shear rate polymer solidification. Journal of Non-Newtonian Fluid Mechanics, 2002, 102(2):397~408
    [148] Tanner R.. On the flow of crystallizing polymers. I. Linear regime. Journal of Non-Newtonian Fluid Mechanics, 2003, 112(2-3):251~268
    [149] Flory P. J.. Theory of elastic mechanisms of fibrous proteins. Journal of American Chemistry Society, 1956, 18:5222~5235
    [150] Krigbaum W. R., Reo R. J.. Diffraction study of crystallite orientation in stretched polychloroprene vulcanizates. Journal of Polymer Science, 1964, A2:4391~4414
    [151] Haas T. W., Maxwell B.. Effects of shear stress on the crystallization of linear polyethylene and poly-1-butene. Polymer Engineering and Science, 1969, 9(4):225~241
    [152] Tan V., Gogos C. G.. Flow-induced crystallization of linear polyethylene above its normal melting point. Polymer Engineering and Science, 1976, 16:512~525
    [153] Eder G., Janeschitz-Kriegl H.. Theory of shear induced crystallization of polymer melts. Colloid & Polymer Science, 1988, 266:1087~1094
    [154] Boutahar K., Carrot C., Guillet J.. Polypropylene during crystallization from the melt as a model for the rheology of molten-filled polymers. Journal of Applied Polymer Science, 1996, 60(1):103~114
    [155] Floudas G., Hilliou L., Lellinger D. et al. Shear-induced crystallization of poly(e- caprolactone). 2. Evolution of birefringence and dichroism. Macromolecules, 2000, 33(17):6466–6472

© 2004-2018 中国地质图书馆版权所有 京ICP备05064691号 京公网安备11010802017129号

地址:北京市海淀区学院路29号 邮编:100083

电话:办公室:(+86 10)66554848;文献借阅、咨询服务、科技查新:66554700