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在真空中成像薄平面液体喷水的温度和厚度
Tillmann Buttersack1, Henrik Haak1, Hendrik Bluhm1
1Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, 14195 Berlin, Germany.
Structural dynamics (Melville, N.Y.)
|July 3, 2023
概括
研究人员在不同压力下测量了液态水微喷射器的温度. 高分辨率的红外成像显示了由于蒸发而导致的快速冷却,经过校正的测量结果产生了准确的厚度映射.
科学领域:
- 流体动力学 流体动力学
- 热力学是一种热力学.
- 光学测量技术的使用.
背景情况:
- 了解液体微喷射的行为对于诸如喷墨印刷和喷雾冷却等应用至关重要.
- 精确的温度和厚度测量对于描述微喷气动态至关重要.
- 热背景辐射可以显著影响微喷射的红外测量.
研究的目的:
- 为了呈现一个平面液态水微喷射器的空间分辨率温度测量.
- 为了研究环境压力对微喷气温度和蒸发的影响.
- 开发一种用于在红外成像中纠正热背景辐射的协议,并推断微射线厚度.
主要方法:
- 使用高分辨率红外 (IR) 摄像头进行单次拍摄,对微喷射器进行全面探测.
- 实施了一种新的协议,以纠正热背景辐射干扰.
- 在各种环境压力范围内进行测量,从真空到100%的相对湿度.
主要成果:
- 观察到显著的冷却速度 (大约. 10^5 K/s) 在真空中由于水的蒸发.
- 在微喷射器上测量了~15K的温度下降.
- 成功推断出微喷射厚度图,与白光干扰测量数据进行验证.
结论:
- 空间分辨率的红外热学对于研究液体微喷流是有效的.
- 蒸发式冷却是微喷气温度动态中占主导地位的因素,特别是在低压下.
- 开发的校正协议可以准确地确定微喷气的厚度.
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