Development of a Dew/Frost Point Temperature Sensor Based on Tunable Diode Laser Absorption Spectroscopy and Its Application in a Cryogenic Wind Tunnel

We have proposed a sensor for real-time and online measurement of dew/frost point temperature using tunable diode laser absorption spectroscopy (TDLAS) technique. Initial experiments have demonstrated its feasibility and technical advantages in comparison to a chilled mirror hygrometer (CMH). The TDLAS sensor we developed has a dew/frost point temperature range from −93 °C to + 14.5 °C, with a measurement uncertainly of less than 2%, and a response time of about 0.8 s, which is much faster than that of the chilled mirror hygrometer (ranging from several minutes to several hours). A TDLAS-based dew/frost point sensor has many advantages, such as rapid and continuous measurements, low frost point temperature sensing, high accuracy, and non-intrusiveness. Such a sensor would be useful for dew/frost point temperature determinations in various applications. In a cryogenic wind tunnel, real-time dew/frost point temperature measurements are helpful in preventing the formation of condensed liquid and ice, which can affect the model geometry and lead to unreliable test data.

[1]  Oliver Ambacher,et al.  Development of a Silicon-Only Capacitive Dew Point Sensor , 2017, IEEE Sensors Journal.

[2]  Volker Ebert,et al.  Validation of an extractive, airborne, compact TDL spectrometer for atmospheric humidity sensing by blind intercomparison , 2013 .

[3]  S. Balakrishna,et al.  Effects of water vapor on cryogenic wind tunnels , 1994 .

[4]  L. Greenspan,et al.  Functional Equations for the Enhancement Factors for CO2-Free Moist Air , 1976, Journal of research of the National Bureau of Standards. Section A, Physics and chemistry.

[5]  Thomas Koop,et al.  Review of the vapour pressures of ice and supercooled water for atmospheric applications , 2005 .

[6]  Dennis L. O'Neal,et al.  The Transient Response of Capacitive Thin-Film Polymer Humidity Sensors , 2008 .

[7]  Lingling Wang,et al.  High performance humidity sensors based on CeO2 nanoparticles , 2015 .

[8]  Franz Schreier,et al.  Computational aspects of speed-dependent Voigt profiles , 2017 .

[9]  Jonathan Tennyson,et al.  HITEMP, the high-temperature molecular spectroscopic database , 2010 .

[10]  Qiang Wang,et al.  Study of a distributed feedback diode laser based hygrometer combined Herriot-gas cell and waterless optical components , 2016 .

[11]  Yoshihiko Sadaoka,et al.  Humidity sensors based on polymer thin films , 1996 .

[12]  Gwo-Bin Lee,et al.  Humidity Sensors: A Review , 2005 .

[13]  Xueli Fan,et al.  A Tunable Diode Laser Absorption Based Velocity Sensor for Local Field in Hypersonic Flows , 2016 .

[14]  Roman W. Paryz.  Recent Developments at the NASA Langley Research Center National Transonic Facility , 2011 .

[15]  Sang-Wook Lee,et al.  The Effect of Temperature on Aluminum Oxide and Chilled Mirror Dew-point Hygrometers , 2017 .

[16]  Azer P Yalin,et al.  Open-path cavity ring-down spectroscopy for trace gas measurements in ambient air. , 2016, Optics express.

[17]  Z. M. Rittersma,et al.  Recent achievements in miniaturised humidity sensors—a review of transduction techniques , 2002 .

[18]  Volker Ebert,et al.  HAI, a new airborne, absolute, twin dual-channel, multi-phase TDLAS-hygrometer: background, design, setup, and first flight data , 2017 .

[19]  Ning Li,et al.  Quartz crystal sensor using direct digital synthesis for dew point measurement , 2018 .

[20]  D. Fahey,et al.  A two-channel, tunable diode laser-based hygrometer for measurement of water vapor and cirrus cloud ice water content in the upper troposphere and lower stratosphere , 2015 .

[21]  E. R. Polovtseva,et al.  The HITRAN2012 molecular spectroscopic database , 2013 .