火箭推进

火箭发动机工作过程中的尾焰会产生强烈的红外辐射,对其结构及载荷有加热的效果,同时一些结构成为了遮挡物体,会影响辐射的传输。为了研究复杂的有遮挡状况下的红外辐射传输,采用反向蒙特卡洛方法,编写气体红外辐射计算程序。计算并分析标准等温流场对其表面的辐射强度,与教材算例对比,验证了红外辐射算法的有效性和正确性。针对某尾焰复燃流场,分别计算并分析尾焰流场有无遮挡两种情况下的气体红外辐射强度。并比较了遮挡物在不同形状、尺寸、位置下产生的影响。研究表明:尾焰的辐射会对发动机结构产生热影响; 增加遮挡后,被遮挡区域的辐射强度数值明显减小; 遮挡的形状、尺寸及位置都会对其效果产生影响。

The exhaust plume in the working process of rocket engine generates strong infrared radiation, which has a heating effect on its structure and load.At the same time, some structures become shading objects and affect the radiation transfer.In order to study the complex infrared radiation under shading conditions, this article uses the Backward Monte Carlo Method(BMCM)to compile an calculation program for the gas infrared radiation.The radiation intensity of the standard isothermal flow field on its surface is calculated and analyzed, which verifies the effectiveness and correctness of the infrared radiation algorithm by comparing with the textbook examples.For the flow field of an afterburning exhaust plume, the infrared radiation intensity of the gas in the case of the flow field with or without shielding is calculated and analyzed, respectively.In addition, the effects of shading objects in different shapes, sizes and positions are compared.The results show that the radiation of exhaust plume has a thermal effect on the engine structure.With shielding, the infrared radiation intensity of the blocked area is significantly reduced.The shape, size and position of the shielding will affect its effect.

引言
1 计算方法
2 计算结果分析
3 结论

图1 闭合空间内的反向光束追踪<br/>Fig.1 Backward beam tracing in closed space

图1 闭合空间内的反向光束追踪
Fig.1 Backward beam tracing in closed space

图2 线段与三角形相交<br/>Fig.2 Segments intersect with triangles

图2 线段与三角形相交
Fig.2 Segments intersect with triangles

表1 等温流场参数<br/>Tab.1 Parameters of isothermal flow field

表1 等温流场参数
Tab.1 Parameters of isothermal flow field

图3 柱面辐射强度结果<br/>Fig.3 Results of cylindrical radiation intensity

图3 柱面辐射强度结果
Fig.3 Results of cylindrical radiation intensity

图4 底面辐射强度结果<br/>Fig.4 Results of bottom radiation intensity

图4 底面辐射强度结果
Fig.4 Results of bottom radiation intensity

表2 例题与程序结果对比<br/>Tab.2 Comparison of example and program results

表2 例题与程序结果对比
Tab.2 Comparison of example and program results

图5 尾焰流场温度云图<br/>Fig.5 Temperature cloud map of flame flow field

图5 尾焰流场温度云图
Fig.5 Temperature cloud map of flame flow field

图6 流场、遮挡面和探测面三者之间相对位置关系<br/>Fig.6 Relative positional relationship among flow field,shading surface and detection surface

图6 流场、遮挡面和探测面三者之间相对位置关系
Fig.6 Relative positional relationship among flow field,shading surface and detection surface

表3 流场遮挡物和探测面几何参数<br/>Tab.3 Geometric parameters of flow field shielding and detection surface

表3 流场遮挡物和探测面几何参数
Tab.3 Geometric parameters of flow field shielding and detection surface

图7 无遮挡时射线发射情形<br/>Fig.7 Radiation emission situation without shielding

图7 无遮挡时射线发射情形
Fig.7 Radiation emission situation without shielding

图8 射线被圆柱体遮挡<br/>Fig.8 Rays blocked by the cylinder

图8 射线被圆柱体遮挡
Fig.8 Rays blocked by the cylinder

表4 计算结果
Tab.4 Calculation results

图9 圆柱遮挡物不同半径下的辐射强度<br/>Fig.9 Radiation intensity at different radius of cylindrical shield

图9 圆柱遮挡物不同半径下的辐射强度
Fig.9 Radiation intensity at different radius of cylindrical shield

图10 圆柱遮挡物不同位置下的辐射强度<br/>Fig.10 Radiation intensity at different positions of cylindrical shield

图10 圆柱遮挡物不同位置下的辐射强度
Fig.10 Radiation intensity at different positions of cylindrical shield

图11 遮挡半角变化<br/>Fig.11 Change of shielding half angle

图11 遮挡半角变化
Fig.11 Change of shielding half angle

表5 推力室设计参数<br/>Tab.5 Design parameters of thrust chamber

表5 推力室设计参数
Tab.5 Design parameters of thrust chamber

图12 3个探测面与发动机的相对位置<br/>Fig.12 Relative position of three detection surfaces and engine

图12 3个探测面与发动机的相对位置
Fig.12 Relative position of three detection surfaces and engine

图13 有遮挡时探测面1发射射线情形<br/>Fig.13 Emitting rays of detecting surface 1 with shielding

图13 有遮挡时探测面1发射射线情形
Fig.13 Emitting rays of detecting surface 1 with shielding

表6 探测点辐射强度数值<br/>Tab.6 Radiation intensity value of detection point

表6 探测点辐射强度数值
Tab.6 Radiation intensity value of detection point

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备注

引言

1 计算方法

2 计算结果分析

3 结论

期刊信息