权益分类	功能权益	普通用户	{{item.name}}会员
{{category.name}}	{{benefitItem.name}}

Development of electrostatic accelerator for ice dust and the aggregates

冰尘和骨料静电加速器的开发

基本信息

批准号：
13554015
负责人：
ARAKAWA Masahiko
金额：
$ 8.77万
依托单位：
HOKKAIDO UNIVERSITY
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
2001
资助国家：
日本
起止时间：
2001 至 2003
项目状态：
已结题

项目摘要

We have developed an electrostatic accelerator to launch a ice dust and ice aggregates at a wide range of velocities from cm/s to km/s. The ice sample launched was prepared by a condensation, method : a cold copper plate cooled by liquid nitrogen was subjected to an air saturated with water vapor at -10℃. The condensed icy dust is an almost spherical shape with the size of 10 μm, Ice aggregates were grown by collecting each ice dust under high electric field more than 100 V/cm. The aggregate was charged under the electric field, so that it was launched by the electrostatic attraction. The relationship between the electric field and the velocity is derived as follows for the aggregates of 500μm.: V_i=0.25(V_<o>/d)^<0.9> (m/s), V_i: velocity, V_o: Voltage, d: distance between electrodes (d=2.5mm). The launch velocity is strongly affected by the air drag for the small aggregates, so we have set a vacuum chamber to eliminate the gas drag to the aggregates in the acceleration. We also used a longer acceleration tube to avoid disruption of the aggregates by the strong attraction force. As a result we have achieved 20m/s for 500μm aggregate at the electric field of 1kV/mm and 1 bar. In the evacuated condition of 0.1 bar, the launched velocity increased about 3 to 4 times higher than that of 1 bar at the same electric field strength. This means that it could be possible to achieve more than 100 m/s for ice aggregate of 500 μm at 1kV/mm.

我们开发了一种静电加速器，可以以厘米/秒到公里/秒的速度发射冰尘和冰聚集体。发射的冰样采用冷凝法制备：将用液氮冷却的冷铜板置于-10℃饱和水蒸气的空气中。在大于100 V/cm的高电场作用下，对每颗冰尘进行收集，形成冰聚集体。聚集体在电场作用下带电，使其受到静电吸引而发射。对于粒径为500μm的聚集体，电场与速度的关系如下：： V_i=0.25(V_< 0 >/d)^<0.9> (m/s)， V_i：速度，V_o：电压，d：电极间距（d=2.5mm）。对于小聚集体，发射速度受空气阻力的影响较大，因此我们设置了真空室来消除加速过程中对聚集体的气体阻力。我们还使用了较长的加速管，以避免聚集体被强大的吸引力破坏。结果表明，在1kV/mm和1bar的电场下，500μm骨料达到了20m/s的速度。在0.1 bar的真空条件下，发射速度比相同电场强度下的1 bar提高了约3 ~ 4倍。这意味着在1kV/mm下，500 μm的冰集料可以达到100 m/s以上。