装药尺寸对高氯酸铵/端羟基聚丁二烯底排药烤燃特性的影响

摘要

To investigate the effect of charge size on the cook-off characteristics of ammonium perchlorate (AP)/ hydroxyl-terminated polybutadiene (HTPB) base bleed propellant,a cook-off model of base bleed propellant grain is established based on the two-step decomposition reaction mechanism of AP/HT-PB.The AP/HTPB propellant is 72 mm in charge length and 43-53 mm in grain diameter,as well as 43 mm in grain diameter and 72-90 mm in charge length.The cook-off characteristics of AP/HTPB base bleed propellant are simulated at the heating rates from 1.0 K/min to 10.0 K/min.The results show that the cook-off time is shortened with the increase in the grain diameter of charge.As the charge length of AP/HTPB propellant with same grain diameter is added to 90 mm,the cook-off time is shortened remarkably.The charge size has little influence on ignition position.At the medium heating rates of 1.0-2.5 K/min,the ignition temperature rises with the increase in grain diameter and charge length.At the fast heating rates of 5.0-10.0 K/min,the charge has a less effect on the ignition temperature of AP/HTPB propellant.%为研究装药尺寸对高氯酸铵(AP)/端羟基聚丁二烯(HTPB)底排药烤燃响应特性的影响,基于AP/HTPB两步分解反应机理,建立底排药柱烤燃计算模型.分别选取装药长度为72 mm和内孔直径为43 ～ 53 mm、内孔直径为43 mm和装药长度为72 ～90 mm的圆环柱状底排药,在1.0 ～ 10.0 K/rmin加热速率下对某底排装置的烤燃特性进行数值模拟.结果表明:在相同加热速率和装药长度条件下,随着装药内孔直径的增大,底排药的烤燃响应时间缩短;当装药内孔直径不变,装药长度增加至90 mm,底排药的烤燃响应时间明显缩短;装药尺寸的变化对底排药的烤燃响应位置的影响较小;在1.0 ～ 2.5 K/min中速烤燃条件下,随着内孔直径和装药长度分别增大,底排药的烤燃响应温度逐渐增大;在5.0～10.0 K/min快速烤燃条件下,装药尺寸的变化对底排药的烤燃响应温度的影响较小.