Primary spacing selection of constrained dendritic growth

1993 ◽  
Vol 134 (1-2) ◽  
pp. 105-115 ◽  
Author(s):  
Huang Weidong ◽  
Geng Xingguo ◽  
Zhou Yaohe
2018 ◽  
Vol 15 ◽  
pp. 128-153
Author(s):  
Hui Xing ◽  
Xiang Lei Dong ◽  
Jian Yuan Wang ◽  
Ke Xin Jin

In this paper, we review our results from phase field simulations of tilted dendritic growth dynamics and dendrite to seaweed transition in directional solidification of a dilute alloy. We focus on growth direction selection, stability range and primary spacing selection, and degenerate seaweed-to-tilted dendrite transition in directional solidification of non-axially orientated crystals. For growth direction selection, the DGP law (Phys. Rev. E, 78 (2008) 011605) was modified through take the anisotropic strength and pulling velocity into account. We confirm that the DGP law is only validated in lower pulling velocity. For the stability range and primary spacing selection, we found that the lower limit of primary spacing is irrelative to the misorientation angle but the upper limit is nonlinear with respect to the misorientation angle. Moreover, predicted results confirm that the power law relationship with the orientation correction by Gandin et al. (Metall. Mater. Trans. A. 27A (1996) 2727-2739) should be a universal scaling law for primary spacing selection. For the seaweed-to-dendrite transition, we found that the tip-splitting instability in degenerate seaweed growth dynamics is related to the M-S instability dynamics, and this transition originates from the compromise in competition between two dominant mechanisms, i.e., the macroscopic thermal field and the microscopic interfacial energy anisotropy.


Crystals ◽  
2020 ◽  
Vol 10 (7) ◽  
pp. 627 ◽  
Author(s):  
Joel Strickland ◽  
Bogdan Nenchev ◽  
Hongbiao Dong

The primary spacing is intrinsically linked with the mechanical behavior of directionally solidified materials. Because of this relationship, a significant amount of solidification work is reported in the literature, which relates the primary spacing to the process variables. This review provides a comprehensive chronological narrative on the development of the directional dendritic growth problem over the past 85 years. A key focus within this review is detailing the relationship between key solidification parameters, the operating point of the dendrite tip, and the primary spacing. This review critiques the current state of directional dendritic growth and primary spacing modelling, briefly discusses dendritic growth computational and experimental research, and suggests areas for future investigation.


1998 ◽  
Vol 194 (2) ◽  
pp. 263-271 ◽  
Author(s):  
Weiqiang Zhang ◽  
Hua Fu ◽  
Yuansheng Yang ◽  
Zhuangqi Hu

Author(s):  
Jing-Shu Sun ◽  
Teng Zhu ◽  
Marcin Wozniak

AbstractCurrent IoT communication node spacing selection process show may potential areas for improvements such as high delay ratio, high total energy consumption ratio, confusion of the optimal communication information band, intelligent spacing node design under the constraints of the energy-saving selection of IoT communication. Based on energy-saving constraints, the link status between nodes is evaluated through link stability and link quality. In order to prevent the generation of serious noisy nodes and frequency hopping data, the interference nodes under the intrusion of the Internet of Things are identified by determining transition amplitude of the noise nodes in the transmission data sequence. Finally, according to the calculation results of the optimal communication node selection, the design of the intelligent spacing selection model for the communication nodes of the Internet of Things is realized. The simulation results show that the established model not only reduces energy consumption of nodes, shortens the average transmission delay of nodes, but also improves anti-interference effect of node spacing selection.


2019 ◽  
Vol 6 (8) ◽  
pp. 0865a8 ◽  
Author(s):  
Yiku Xu ◽  
Zhaohao Huang ◽  
Junxia Xiao ◽  
Xuding Song ◽  
Lin Liu

Sign in / Sign up

Export Citation Format

Share Document