基于SIFT算法的含碳颗粒凝胶推进剂雾化场速度分析

Analysis of Atomization Field Velocity of Carbon-Loaded Gelled Propellants Based on SIFT Algorithm

关键词:  凝胶推进剂  碳颗粒  雾化场速度  SIFT算法

Key words:  Gelled propellants  Carbon particles  Atomization field velocity  SIFT algorithm

摘要:

雾化是凝胶推进技术的关键问题之一，雾化过程中的液膜、液丝及液滴等的速度分布、液膜厚度等参数对于判断雾化效果、揭示雾化机理具有重要作用。为了对含碳颗粒凝胶推进剂雾化场的速度进行定量分析，提出了一种基于SIFT关键点匹配的雾化场速度计算方法，并以雾化场速度分析为基础，提出了一种新的液膜厚度估算方法。结果表明:雾化场速度随射流速度的增大而增大，随撞击角度的增大而减小；雾化场平均速度与射流速度的比值[vato/vjet]在0.6～0.9，可用于表征雾化效果，[vato/vjet]越小，雾化效果越好；射流撞击形成液膜的厚度在0.04～0.13mm，液膜厚度随着射流速度及撞击角度的增大而减小；凝胶推进剂的雾化效果随着碳颗粒浓度的增大而降低，随着碳颗粒粒径的增大而略有改善。

Abstract:

Atomization is one of the key problems in gel propulsion technology， and the velocity distribution of liquid sheets， liquid filaments or droplets and the liquid sheet thickness play an important role in judging the atomization effect and revealing the atomization mechanism. In order to quantitatively analyze the atomization field velocity of carbon-loaded gelled propellants， a method of atomization field velocity calculation was proposed， which was based on the SIFT key points of atomization images， and a new liquid sheet thickness estimation method was put forward. The results show that atomization field velocity increases with jet velocity， and decreases with the increase of impact angle; the ratio of atomization average velocity to jet velocity[vato/vjet] can be used to characterize the atomization effect， which is between 0.6～0.9， the smaller the [vato/vjet]is， the better is the atomization effect; the thickness of liquid sheet formed by impinging jet is between 0.04～0.13mm， and the liquid sheet thickness decreases with the increase of jet velocity and impact angle; the atomization effect can be weakened as the mass fraction of carbon particles increases and slightly improved as the average radius of carbon particles increases.