For beam profile measurement of high-intensity proton beams in the low-energy high-intensity proton accelerator at Bhabha Atomic Research Centre, a recent noninvasive technique based on gas sheets will be explored. The gas sheet for this instrument needs to be characterized for calibration and fine tuning of the sheet properties to provide better profile measurements. Pulsed sheet generators for similar applications have been characterized using movable vacuum chambers with a small slit and a gauge mounted inside. Pitot probes are more compact instruments and have been used to measure gas jet profiles in molecular beam applications where the jet was not pulsed. The performance of Pitot probes in the measurement of pulsed supersonic gas flow in vacuum was, therefore, investigated in this work. A test system was developed to generate a pulsed supersonic gas jet in vacuum, and a Pitot probe was inserted into the flow at various axial locations with respect to the nozzle. Measurements taken along the nozzle axis using this probe, as well as the axial Mach number and impact pressure computed using computational fluid dynamics and direct simulation Monte Carlo algorithms, were compared with fitting formulas. Schlieren images of the jet with and without the Pitot tube were also taken under different vacuum conditions.

中文翻译：

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束轮廓监测仪中脉冲超音速气流表征的皮托管探针响应

为了在Bhabha原子研究中心的低能量高强度质子加速器中测量高强度质子束的光束轮廓，将探索一种基于气体薄层的最新无创技术。需要对该仪器的气体薄板进行特征化，以校准和微调薄板性能，以提供更好的轮廓测量。用于类似用途的脉冲薄板发生器的特征是使用可移动的真空室，该室具有一个小缝隙和一个安装在内部的量规。皮托管探头是一种更紧凑的仪器，已用于在没有脉冲束的分子束应用中测量气体的喷射轮廓。因此，在这项工作中研究了皮托探针在真空中测量脉冲超音速气流的性能。开发了一种测试系统以在真空中产生脉冲式超音速气体射流，并将皮托管探头相对于喷嘴的各个轴向位置插入流中。使用该探头沿喷嘴轴线进行的测量，以及使用计算流体力学和直接模拟蒙特卡洛算法计算出的轴向马赫数和冲击压力与拟合公式进行了比较。带有和不带有皮托管的射流的Schlieren图像也是在不同的真空条件下拍摄的。与拟合公式进行了比较。带有和不带有皮托管的射流的Schlieren图像也是在不同的真空条件下拍摄的。与拟合公式进行了比较。带有和不带有皮托管的射流的Schlieren图像也是在不同的真空条件下拍摄的。