کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
10262751 | 457066 | 2005 | 9 صفحه PDF | دانلود رایگان |
عنوان انگلیسی مقاله ISI
Acoustic initiation of powder flow in capillaries
دانلود مقاله + سفارش ترجمه
دانلود مقاله ISI انگلیسی
رایگان برای ایرانیان
موضوعات مرتبط
مهندسی و علوم پایه
مهندسی شیمی
مهندسی شیمی (عمومی)
پیش نمایش صفحه اول مقاله

چکیده انگلیسی
Second generation solid freeforming devices will have the capability to render both shape and the spatial arrangement of composition directly from a computer file. In order to build three-dimensional functional gradients in selective laser sintering it is necessary to have a computer-controlled mixing and dispensing system. We report such a system based on the horizontal acoustic vibration of vertical capillary tubes that provides both switching and flow rate control. An orchestra of such tubes can be constructed to deposit a multi-component system onto a building platform. Our concern is the initiation of flow. It requires an “attack” waveform to break the domes that provide flow arrest and release the potential energy of powder above the dome. The intensity of attack also influences the mass that flows out before a new dome forms, i.e., the response time of the valve. Neither the extension to vibration caused by ringing nor the wave amplitude account for the over-run of the valve. Much better correlation is obtained with acceleration and with calculated kinetic energy of horizontally vibrating particles.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Chemical Engineering Science - Volume 60, Issue 2, January 2005, Pages 413-421
Journal: Chemical Engineering Science - Volume 60, Issue 2, January 2005, Pages 413-421
نویسندگان
Shoufeng Yang, Julian R.G. Evans,