Purpose

The purpose of this study is to experimentally investigate the trends in shock wave Mach number that were observed when different diaphragm material combinations were used in the small-scale shock tube.

Design/methodology/approach

A small-scale shock tube was designed and fabricated having a maximum Mach number production capacity to be 1.5 (theoretically). Two microphones attached in the driven section were used to calculate the shock wave Mach number. Preliminary tests were conducted on several materials to obtain the respective bursting pressures to decide the final set of materials along with the layered combinations.

Findings

According to the results obtained, 95 GSM tracing paper was seen to be the strongest reinforcing material, followed by 75 GSM royal executive bond paper and regular 70 GSM paper for aluminium foil diaphragms. The quadrupled layered diaphragms revealed a variation in shock Mach number based on the position of the reinforcing material. In quintuple layered combinations, the accuracy of obtaining a specific Mach number was seen to be increasing. Optimization of the combinations based on the production of the shock wave Mach number was carried out.

Research limitations/implications

The shock tube was designed taking maximum incident shock Mach number as 1.5, the experiments conducted were found to achieve a maximum Mach number of 1.437. Thus, an extension to further experiments was avoided considering the factor of safety.

Originality/value

The paper presents a detailed study on the effect of change in the material and its position in the layered diaphragm combinations, which could lead to variation in Mach numbers that are produced. This could be used to obtain a specific Mach number for a required study accurately, with a low-cost setup.

中文翻译：

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小型激波管中膜片材料组合的实验研究

目的

这项研究的目的是实验研究在小型冲击管中使用不同膜片材料组合时观察到的冲击波马赫数趋势。

设计/方法/方法

设计和制造的小型冲击管的最大马赫数生产能力为1.5（理论上）。使用驱动部分中安装的两个麦克风来计算冲击波马赫数。对几种材料进行了初步测试，以获得各自的破裂压力，以确定最终的材料组以及分层组合。

发现

根据获得的结果，可以看到95 GSM描图纸是最坚固的增强材料，其次是75 GSM皇家执行性粘合纸和70 GSM常规铝箔隔膜纸。四重的分层隔膜显示了基于增强材料位置的冲击马赫数变化。在五重分层组合中，发现获得特定马赫数的准确性正在提高。根据冲击波马赫数的产生来优化组合。

研究局限/意义

设计冲击管时，最大入射冲击马赫数为1.5，所进行的实验发现最大马赫数为1.437。因此，考虑到安全因素，避免了扩展到进一步的实验。

创意/价值

本文对材料变化及其在分层隔膜组合中的位置的影响进行了详细研究，这可能会导致产生的马赫数发生变化。这可以用于以低成本设置准确获得所需研究的特定马赫数。