冲压发动机用梯度隔热层隔热性能研究

Investigation on Insulation Performance of Gradient Thermal Insulation for Ramjet

关键词:  冲压发动机  被动热防护  狭小空间  大温度梯度  梯度隔热

Key words:  Ramjet  Passive thermal protection  Narrow space  Large temperature gradient  Gradient thermal insulation

摘要:

为了解决冲压发动机被动热防护结构在长时间、狭小空间、大温度梯度下的隔热问题，提出了多层组合梯度隔热方案。通过不同构型的梯度隔热层的氧乙炔实验研究，优化了梯度隔热层的构型，并对优化后的梯度隔热材料的隔热性能进行了冲压发动机试验验证。研究表明:2100K的高温下柔性梯度隔热层具有良好的隔热性能，能够解决狭小空间、大温度梯度条件下，冲压发动机长时间工作的隔热问题；梯度隔热材料的层数影响隔热层的隔热性能，较多的层数可提高柔性梯度材料的整体隔热性能；梯度隔热材料的隔热性能可采用氧乙炔隔热实验进行表征。

Abstract:

In order to solve the heat insulation problem of the ramjet passive thermal protection structure in long duration working condition，narrow space and large temperature gradient，a gradient heat insulation scheme with multi-layers was proposed for ramjet. By oxy-acetylene experiments of the gradient thermal insulation with different configurations，gradient thermal insulation configuration was optimized，and insulation performance of gradient thermal insulation optimized was successfully tested with ramjet. The results show that the flexible gradient thermal insulation has good insulation performance under 2100K，can solve the heat insulation problem with narrow space and large temperature gradient of the ramjet working for a long time. Layers of gradient thermal insulation affect the insulation performance，and more layers can improve the insulation performance. Thermal insulation performance of graded insulation can be characterized by oxy-acetylene test.