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注塑冷却管网的简化计算 总被引:1,自引:0,他引:1
给出了作者推导的冷却管道椭圆积分项计算公式,分析了它的复杂性,采用降维处理方法,将原来的二维管道单元简化为一维线单元,简化了计算,提高了计算速度,缩短了计算时间。 相似文献
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平板塑件瞬态传热解析解及其在冷却分析中的应用 总被引:4,自引:0,他引:4
简要介绍了建立冷却分析数学模型的两种方法,指出了循环迭代模型的不足,推导了平板塑件瞬态传热解析解,找出循环平均热流与边界温度的线性关系表达式,并将它应用于注塑冷却分析,建立了冷却分析的迭代模型,取代原来的循环迭代模型,从而取消了原冷却分析中的中间迭代计算,有效地减少了冷却分析的迭代次数,提高了运算效率。另外,循环迭代求解平板塑件温度场采用的是有限差分法,即近似数值解,而迭代模型采用的是解析解,从理论上讲结果更精确,所以对提高计算结果的精度有一定的改善作用。 相似文献
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带筋平板注塑件的冷却模型分析 总被引:2,自引:0,他引:2
通过对带筋平板注塑件的分析,提出了该类注塑件的冷却物理模型,简化后用数学模型表征。将精确分析解法与积分近似解法相结合,求得了固液两相内的温度分布、固液相位置函数和中心层温度冷至熔点所需的冷却时间。讨论了带筋平板注塑件保压冷却阶段的最佳工艺设定时问。 相似文献
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结晶型塑料注塑平板冷却模型的研究 总被引:6,自引:3,他引:6
本文从注塑的实际出发,针对注塑塑料平板的冷却凝固本质,提出了有限厚度区域内注塑平板的冷却模型,用精确分析解法与积分近似解法相结合,进行了理论推导,求得了固液两相内的温度分布和平板中心层温度冷却至熔点所需的冷却时间。 相似文献
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A theoretical mathematical model is presented to describe the temperature distribution and the rate of phase change in the injection molding process of crystalline plastics. Under some assumptions, an exact closed form is solved with the use of an internal technique. The model was tested by measuring the temperature profile in a slab mold instrumented with thermocouples. Measurements of temperature profiles in the center of the polymer slab compare well to model prediction. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 2249–2253, 2006 相似文献
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以家用榨汁机机身注塑模冷却系统设计为例,根据其模具结构特点制定了2种冷却系统设计方案,运用Moldflow 2012对2种方案的冷却时间、冷却介质温度、冷却不均翘曲变形量等进行分析比较。结果表明,多层直通式冷却系统优于多层回路式冷却系统,通过对多层直通式冷却系统的进一步优化得到适于家用榨汁机机身注塑模的冷却系统的最佳设计方案。 相似文献
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Plastic injection molding (PIM) is well known as a manufacturing process to produce products with various shapes and complex geometry at low cost. Determining optimal settings of process parameters critically influence productivity, quality, and cost of production in the PIM industry. To study the effect of the process parameters on the cooling of the polymer during injection molding, a full three‐dimensional time‐dependent injection molding analysis was carried out. The studied configuration consists of a mold having cuboids‐shaped cavity with two different thicknesses and six cooling channels. A numerical model by finite volume was used for the solution of the physical model. A validation of the numerical model was presented. The effect of different process parameters (inlet coolant temperature, inlet coolant flow rate, injection temperature, and filling time) on the cooling process was considered. The results indicate that the filling time has a great effect on the solidification of the product during the filling stage. They also show that low coolant flow rate increases the heterogeneity of the temperature distribution through the product. The process parameter realizing minimum cooling time not necessary achieves optimum product quality and the complete filling of the cavity by the polymer material. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009 相似文献
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研究了模具随形冷却结构对制品成型的热响应变化,利用有限元软件Ansys对线性与随形2种冷却结构进行瞬态热响应分析与对比,得到了2种结构模式的冷却效率和型腔温度场分布规律,并借助Moldflow和计算流体动力学(CFD)软件对注塑制品在随形冷却结构模式下成型所得到的温度场分布及其可能产生的缺陷进行了分析研究。结果表明,随形冷却结构较传统水道具有更均匀的冷却效果,冷却时间缩短了50 %,体积收缩率降低了15 %,且能更迅速地调控模具温度,更快地进入稳定的工作状态。 相似文献
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Yung-Hsiang Chang Min-Chi Chiu Shia-Chung Chen Che-Wei Chang Chia-Yen Tseng 《Polymer Engineering and Science》2020,60(12):3072-3085
Injection molding is one of the most widely-used processes for the production of plastic parts, due to the utilization of diverse materials, the complex product-shape moldability, and the rapid mass production. In relation to the environmental issues, light-weight technology and green molding solutions are becoming more important. Microcellular injection molding technology is one of the green molding solutions for saving materials, as well as reducing the weight of molded parts. However, the molding process brings about some defects, including a sliver flow mark on the surface and uneven mechanical properties that are caused by the uneven cell size and their distribution within the part. Dynamic molding temperature control technology seems to be an effective way of improving the product quality. Until recently, there has been very little discussion about high-efficiency cooling methods. A new complex mold for a cooling system has been designed. The basis cooling ability of different materials was investigated. The complex mold design has a faster cooling rate, and it has a greater surface temperature uniformity. This cooling technology was used to improve the quality of microcellular injection molded parts, which improves the glossy finish by about 73%. The results show that the faster cooling rate brings about the more uniform cell size with higher cell density from 9.43E+11 to 1.92E+12 cells/cm3. Otherwise, the cell size reduced from 192.92 to 84.97 μm. 相似文献