Hot wire anemometer (HWA) is a widely used instrument to perform experimental measurements in laminar, transitional and turbulent flows. A pure, low-cost tungsten filament from an ordinary light bulb is utilized as a hot wire sensor for the analysis of different configurations of constant voltage anemometer (CVA). Experiments are carried out with the proposed sensor for all the three modes of CVA in a self-designed wind tunnel with the laminar flow; the measured velocities are in the mean range of 0.13 m/s to 0.37 m/s. The low-cost sensor is capable of maintaining a constant voltage in spite of the variation in the sensor current caused by fluctuations in the air velocity, in comparison with any commonly used hot wire sensors. Uncertainty analysis is carried out for the proposed low-cost sensor-based CVA measurement system. The maximum standard uncertainty for the output voltage of CVA is less than 0.229 mV for the whole range of measurement. The uncertainty budget is presented along with the estimating procedure. The expanded uncertainties with a 95% confidence level for the basic, compensated and composite CVA are 0.5092, 0.4028 and 0.5148, respectively. This CVA measurement system with an alternative low-cost sensor in a self-designed wind tunnel for laminar flow is a simple, inexpensive and compact model and is proved to be an equitable standby for the CVA Tao systems.

中文翻译：

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低成本传感器恒压风速计的实验研究及不确定度分析

热线风速计 (HWA) 是一种广泛使用的仪器，用于在层流、过渡流和湍流中进行实验测量。来自普通灯泡的纯低成本钨丝用作热线传感器，用于分析不同配置的恒压风速计 (CVA)。在自行设计的层流风洞中，使用所提出的传感器对 CVA 的所有三种模式进行了实验；测得的速度在 0.13 m/s 到 0.37 m/s 的平均范围内。与任何常用的热线传感器相比，这种低成本传感器能够保持恒定电压，尽管空气速度的波动会导致传感器电流发生变化。对所提出的基于传感器的低成本 CVA 测量系统进行了不确定性分析。在整个测量范围内，CVA 输出电压的最大标准不确定度小于 0.229 mV。不确定性预算与估计程序一起提供。基本、补偿和复合 CVA 具有 95% 置信水平的扩展不确定性分别为 0.5092、0.4028 和 0.5148。这种 CVA 测量系统在自行设计的层流风洞中带有替代的低成本传感器，是一种简单、廉价且紧凑的模型，并被证明是 CVA Tao 系统的公平备用。分别。这种 CVA 测量系统在自行设计的层流风洞中带有替代的低成本传感器，是一种简单、廉价且紧凑的模型，并被证明是 CVA Tao 系统的公平备用。分别。这种 CVA 测量系统在自行设计的层流风洞中带有替代的低成本传感器，是一种简单、廉价且紧凑的模型，并被证明是 CVA Tao 系统的公平备用。