Fast Settling Millimetre-Scale Five-Hole Probes
Fast Settling Millimetre-Scale Five-Hole Probes
复制标题
快速稳定毫米级五孔探头
DOI：
--
复制
发表时间：
2016
期刊：
影响因子：
--
通讯作者：
James V. Taylor
中科院分区：
文献类型：
--
作者：
S. Grimshaw;James V. Taylor
版权所有© 2016 ASME。本文研究了五孔探针的外部几何形状如何影响其精度以及内部几何形状如何影响其建立时间。一个分析模型，预测建立时间，是用来设计一个准确的，快速解决，毫米级探头。本文有三个组成部分：第一，结果是从一系列的区域进行遍历与五孔探头，头部直径范围从0.99到2.67毫米。它被发现，最小的探头提供了最大的精度时，穿越剪切层叶片尾流。然而，与最大的探针相比，完成此遍历所需的时间长3.4倍。这是因为使用小探头的横移需要更多的时间来允许压力读数在每个横移位置之间稳定下来。其次，开发了一种分析模型，该模型根据探头的内部几何形状预测稳定时间。所采用的方法是能够模拟任何数量的连接管具有不同的长度和直径。它是对实验测量验证，并给出了良好的协议。该模型可用于确保探针设计具有可接受的建立时间。最后，利用该分析模型对五孔探针进行了优化设计。该模型的使用突出了两个重要的结果，这是需要减少建立时间：首先，最小直径管的长度，即在探头头，应尽量减少。其次，应尽量减少头部下游的管路体积。将这些原理应用到新的探头设计中，可将总遍历时间缩短71%，同时保持最高的精度值。
Copyright © 2016 by ASME. This paper investigates how the external geometry of a five-hole probe affects its accuracy and how internal geometry affects its settling time. An analytical model, which predicts settling time, is used to design an accurate, fast-settling, millimetre-scale probe. The paper has three components: First, results are presented from a series of area traverses performed with five-hole probes which range in head diameter from 0.99 to 2.67 mm. It is found that the smallest probe gives the greatest accuracy when traversing the shear layers in blade wakes. However, it takes 3.4 times longer to complete this traverse than compared to the largest probe. This is because traverses with small probes require more time to allow the pressure readings to settle between each traverse position. Second, an analytical model is developed which predicts settling time based upon the internal geometry of the probe. The approach adopted is capable of modeling any number of connected tubes with different lengths and diameters. It is validated against experimental measurements and is shown to give good agreement. This model can be used to ensure that probes are designed with acceptable settling times. Finally, the analytical model is used to design an optimised five hole probe. Use of the model highlights two important results which are required to reduce settling time: First, the length of the smallest diameter tubes, i.e. The ones in the probe head, should be minimised. Second, the volume of tubing downstream of the head should be minimised. Applying these principles to a new probe design cuts the total traverse time by 71%, whilemaintaining the highest value of accuracy.