著者

Tomohiro TAKAKI Kazuya NAKAGAWA Yusuke MORITA Eiji NAKAMACHI

出版者

一般社団法人日本機械学会

雑誌

Mechanical Engineering Journal (ISSN:21879745)

巻号頁・発行日

vol.2, no.3, pp.15-00063-15-00063, 2015 (Released:2015-06-15)

参考文献数

61

被引用文献数

1 6

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In this study, we applied a modified Kobayashi-Warren-Carter (KWC) phase-field model to the neurite growth process. To confirm the applicability of this model, we observed axonal extension of PC-12D cells cultured with nerve growth factor (NGF). Based on our observations, we defined three stages of nerve cell axonal extension: neurite generation, neurite contraction, and axon extension. We further determined the parameters in the phase-field equations to express the three extension stages. Finally, our results show that the modified KWC phase-field model reasonably expresses the morphologies of nerve cells and predicts the three stages of nerve cell axonal extension. Although, we employed the binary alloy solidification model as a sample model in the present phase-field simulations, this work will be extensible to relatively more realistic models for nerve cell growth.

著者

Tomohiro TAKAKI Kazuya NAKAGAWA Yusuke MORITA Eiji NAKAMACHI

出版者

一般社団法人日本機械学会

雑誌

Mechanical Engineering Journal (ISSN:21879745)

巻号頁・発行日

pp.15-00063, (Released:2015-05-22)

参考文献数

61

被引用文献数

1 6

---

In this study, we applied a modified Kobayashi-Warren-Carter (KWC) phase-field model to the neurite growth process. To confirm the applicability of this model, we observed axonal extension of PC-12D cells cultured with nerve growth factor (NGF). Based on our observations, we defined three stages of nerve cell axonal extension: neurite generation, neurite contraction, and axon extension. We further determined the parameters in the phase-field equations to express the three extension stages. Finally, our results show that the modified KWC phase-field model reasonably expresses the morphologies of nerve cells and predicts the three stages of nerve cell axonal extension. Although, we employed the binary alloy solidification model as a sample model in the present phase-field simulations, this work will be extensible to relatively more realistic models for nerve cell growth.

著者

Hiroyuki YOSHIDA Taku NAGATAKE Kazuyuki TAKASE Akiko KANEKO Hideaki MONJI Yutaka ABE

出版者

一般社団法人日本機械学会

雑誌

Mechanical Engineering Journal (ISSN:21879745)

巻号頁・発行日

vol.1, no.4, pp.TEP0025-TEP0025, 2014 (Released:2014-08-15)

参考文献数

10

被引用文献数

1 1

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In this study, to develop the predictive technology of two-phase flow dynamics under earthquake acceleration, a detailed two-phase flow simulation code with an advanced interface tracking method TPFIT was expanded to perform two-phase flow simulations under seismic conditions. In the expansion of the TPFIT, the oscillating acceleration attributed to the earthquake motion was introduced into the momentum equation of the two-phase flow as body force. Moreover, to simulate fluctuation of the flow rate and a shear force on a pipe wall, time dependent boundary conditions can be added in the numerical simulations. The bubbly flow in a horizontal pipe excited by oscillation acceleration and under the fluctuation of the liquid flow was simulated by using the modified TPFIT. Furthermore, predicted velocity distribution around the bubbles and shapes of bubbles were compared with measured results under flow rate fluctuation and structure vibration. In the results of numerical simulation, periodical change of shapes of bubbles was observed. In addition, velocity distribution around bubbles also changed in accordance with flow rate fluctuation or structure vibration. Predicted results almost agreed with measured results. In the results, it was confirmed that the modified TPFIT can predict time dependent velocity distribution around the bubbles and shapes of bubbles qualitatively. The main cause of bubble deformation observed from the measured and predicted results is large shear stress at the lower part of the bubble, and this large shear stress is induced by the velocity difference between the liquid phase and bubble. Moreover, by using the predicted results, we discussed about the difference between both effects of flow rate fluctuation and structure vibration on two-phase flow. In the results, bubble acceleration of the structure vibration case was larger than that of the flow rate fluctuation case. Finally, it was concluded that unsteady shear stress induced by vibration of the pipe wall was one of the main driving forces of bubble motion in structure vibration case.