RTD Temperature Sensors Research Articles

Performance Analysis of Vortex Tube Refrigeration System by Experimental Method and Using ANN

Vortex tube is a non-conventional cooling device, having no moving parts which will produce cold air and hot air from the source of compressed air without affecting the environment. When a high-pressure air is tangentially injected into vortex chamber, a strong vortex flow will be created which will split into two air streams, one hot stream at the periphery and the other cold stream at the inner core on both the ends. It can be used in the industrial applications such as spot cooling of cutting tools, heating process, refrigerators etc. It is weightless and requires less space. Also, the initial cost is low and its working expenses are less where compressed air is readily available. The present work is to analysis the performance of vortex tube by changing the mass flow rate of air at inlet and cold outlet. Vortex tube refrigeration system set up is fabricated with the help of instruments such as rotameter, pressure transmitter and RTD temperature sensors. In this experiment, a small vortex tube which is made up of stainless steel is used. The vortex tube is well insulated with a suitable insulating material. The experiment is carried out by varying the thermo-physical properties of the compressed air which is used as working fluid. By regulating the hot end control knob of vortex tube, the pressure, mass flow rate and temperature of air is measured at different points for various inlet working pressure.

Twin-CQCM and Twin-TQCM Sensors With Wide Operating Temperature Range for Outgassing and Atomic Oxygen Measurement

In this paper, we propose a new Quartz Crystal Microbalance (QCM) sensor with temperature control, which can assess outgassing properties during spacecraft development. It will be referred to as the “Twin-QCM sensor”. There are two types. The Twin-Cryogenic QCM (Twin-CQCM) sensor is warmed by a built-in heater with an operating temperature of -190 to +125°C, and the Twin-ThermoelectricQCM (Twin-TQCM) sensor is warmed and cooled by a built-in Peltier module that can control the temperature within -80 to +125°C. Using a temperature compensation technique, the temperature-dependent drift of the frequency was found to be less than ±10 ppm over all operating temperatures. An RTD temperature sensor was mounted on the quartz crystal to improve the accuracy of temperature measurement. To confirm the accuracy, an additional temperature sensor installed at the center of the crystal. The sensor output temperature value was compared to that of the additional sensor, with the difference between both temperature sensors being +0.4 to +2.6°C in the temperature range from -130 to +100°C. Through the measurement of the sensor's dynamic range, it was found that the deposited contaminant film in a vacuum increasingly changed such physical properties as viscoelasticity as the temperature increases.

A versatile low-cost experimental set-up and measurement protocol for temperature dependent electrical measurements in the temperature range 100 K – 500 K

A versatile low-cost experimental set-up and adjoining measurement protocol for continuous temperature dependent electrical measurements in the temperature range of 100 K – 500 K is described. The set-up can perform continuous measurements of DC and AC electrical properties of a sample under test (SUT) as a function of its temperature in the mentioned temperature range without any artefacts. The SUT can be in the form of film, or, powders pressed into pellets. The set-up comprises of automatic data acquisition system equipped with LabVIEW programme for real time data acquisition during measurements. The errors involved in the measurements using the set-up have been calculated by measuring the temperature dependent resistance of standard Pt100 RTD temperature sensor and from temperature response of dielectric constant of standard polycrystalline BaTiO3. The high measurement accuracy of the present set-up in artefact-free AC and DC electrical measurements has been demonstrated by measuring the temperature response of the electrical properties of standard polycrystalline BaTiO3, standard polycrystalline SnO2 and nano polycrystalline SnO2 samples.

Design and implementation of smart web sensors

This paper presents the design and implementation of the smart web sensors. The paper briefly describes the concept of automatic configuration based on electronic specifications in industrial measurement and control systems as well as in distributed systems based on the OGC SWE family of standards. The model for the implementation of Plug and Play sensor in accordance with the IEEE 1451 family of standards is analyzed in detail. Special attention is paid to the network connectivity of analog sensors in accordance with IEEE 1451.4. The practical implementation of the 1451.4 compatible network processor for RTD temperature sensors and adequate software support for 1451.4 TEDS generation, are included in the paper.

곡면 유리 표면 위에서 박막 측온저항체 온도센서 어레이 제작 및 성능 평가

This paper presents a novel direct fabrication method of the thin metal film RTD temperature sensor array on an arbitrary curved surface by using MEMS technology to measure a distributed temperature field up to without disturbing a fluid flow. In order to overcome the difficulty in the three dimensional photography of sensor patterning, the UV pre-irradiated photosensitive dry film resist technology has been developed newly. This method was applied to the fabrication of the temperature sensor array on a glass tube, which is arranged parallel and transverse to a main flow. Gold was used as a temperature sensing material. The resistance change was measured in a thermally controlled oven by increasing the environmental temperature. The linear increase in resistance change and a constant slope were obtained. Also, the sensitivity of each RTD temperature sensor was evaluated.

Heat transfer measurements on ammonia forced convection boiling in vertical tubes

Abstract This paper tackles a subject of present interest. It contributes to the promotion of small capacity refrigerating systems working with ammonia – an ecologically and highly efficient refrigerant – as an alternative to the traditional commercial refrigeration, heat pumps and air-conditioning systems working with CFC refrigerants. Since a literature survey showed that available theoretical methods have not been sufficiently experimentally validated, the authors focused on constructing a test facility, namely a test loop, assisted by a data acquisition system. Experiments have been run in order to develop a data bank for the heat transfer of ammonia inside an electrically heated tube. The local heat transfer coefficient for boiling ammonia was measured in 10 different locations along the tube and the flowing regime was visualized in three locations, using segments of glass tube. Sequences of computerized collected data (from pressure transducers, thermocouples, platinum RTD temperature sensors, and an ultrasound flowmeter) were treated with a digital filtration. A comparison between theoretical and experimental results indicated that the Steiner–Taborek and Gungor–Winterton correlations make the best predictions for the local heat transfer coefficient of boiling ammonia. In addition, the authors experimentally determined the fluid coefficient to be used in Kandlikar's correlation in order to extend its applicability to ammonia boiling. It is shown the influence that the main parameters have on the boiling process, over a range of the input parameters. Both the developing of the two-phase flow mechanisms and the heat transfer coefficients characterizing ammonia boiling inside tubes, are strongly influenced by those parameters.