【摘要】 为了提高航天器控制力矩陀螺的使用寿命,提出一种可按需喷油润滑的润滑系统.润滑系统由储油器和基于按需喷墨(DOD)打印技术的压电润滑装置组成.为了解决润滑油液滴喷射过程中在液气两相流体界间连续拓扑变化问题,采用流体体积算法中的分段线性界面构造技术分析两相界面间的运动.基于两相流体积算法,利用计算机仿真方法对润滑油液滴喷射过程进行有限元分析.重点对不同喷孔形状和空间温度变化对润滑油微喷过程的影响情况进行了分析.实验结果表明,喷孔直径越大,产生液滴越困难;空间温度变化对润滑油液滴的速度有影响,但对液滴形成时间影响却很小.更多还原

【Abstract】 To obtain a longer longevity of control momentum gyroscopes in spacecraft,a positive-feed on-demand lubricating system was proposed.The system consists of an oil container and a piezoelectric lubricating device based on drop on demand technology.To solve the interface movements with continuing topology changes during the ejection process,volume-of-fluid method along with the piecewise linear interface construction technique was implemented to describe the interfacial movements.A computational approach based on VOF(volume of fluid) method was applied to analyze the ejection process of lubricating oil droplet.In simulations,the ejection process of lubricating oil was examined by varying diameter of nozzle and temperature in the aerospace.The experimental results show that it is difficult to form droplet with larger nozzle,and the variety of space temperature has impact on the lubricating oil droplet velocity,but little effect on the formation time.更多还原