Laboratory-scale hybrid rocket motor uncertainty analysis
Laboratory-scale hybrid rocket motor uncertainty analysis
复制标题
实验室规模混合火箭发动机不确定性分析
DOI：
10.2514/3.24076
复制
发表时间：
1996
影响因子：
1.9
通讯作者：
B. Greiner
中科院分区：
文献类型：
--
作者：
R. Frederick;B. Greiner
实验室规模的混合火箭发动机往往提供了评估新燃料配方燃烧速率的手段。虽然缩放到更大尺寸的问题可能很重要，但实验室规模结果的不确定性水平也需要评估。定量评估了某固液火箭发动机关键实验结果的不确定度。范围包括计算的不确定性，在燃料的回归率，氧化剂通量，电机的特征速度，和氧化剂与燃料的质量比为实验室规模的电机。发动机在预燃室的特征条件下燃烧气态氧和端羟基聚丁二烯。科尔曼和斯蒂尔的公认不确定度方法确立了研究方法。结果表明，燃料退减率、氧化剂流量、发动机特征速度和氧化剂燃料比的典型不确定度分别为±8.7%、± 10.8%、±10.5%和±9.2%。初始燃料颗粒、初始进气道和喷管喉部直径的测量不确定性对这些结论有很大的影响。在确定燃烧持续时间、平均燃烧室压力和平均燃烧速率方面的概念偏差具有显著的影响。该评估揭示了重要的测量限制和潜在的改进，为特定的测试条件和数据简化方程使用。然而，所提出的方法一般适用于混合火箭试验。
Laboratory-scale hybrid rocket motors often provide the means to evaluate the burning rates of new fuel formulations. While the issue of scaling to larger sizes can be significant, the uncertainty level of the laboratory-scale results also needs evaluation. This work quantitatively evaluates the uncertainty of key experimental results for a particular hybrid rocket motor. The scope includes calculation of the uncertainties in the fuel regression rate, oxidizer flux, motor characteristic velocity, and the oxidizer-to-fuel mass ratio for a laboratory-sca le motor. The motor burned gaseous oxygen and hydroxyl-terminated polybutadiene at conditions characteristic of a preburner. The accepted uncertainty methodology of Coleman and Steele established the approach for the study. The results show that the typical uncertainty values are ±8.7% hi the determination of the fuel regression rate, ±10.8% in the oxidizer flux, ±10.5% for motor characteristic velocity, and ±9.2% for the oxidizer-to-fuel ratio. Measurement uncertainties hi the diameters of the initial fuel grain, initial port, and nozzle throat contributed significantly to these conclusions. Conceptual biases in determining the burn duration, the average chamber pressure, and the average burning rate have a significant influence. This evaluation revealed the important measurement limitations and potential improvements for the particular test conditions and data reduction equations used. However, the methodology presented is in generally applicable to hybrid rocket testing.