scholarly journals Nanogap Pirani Sensor Operating in Constant Temperature Mode for Near Atmospheric Pressure Measurements

Proceedings ◽  
2017 ◽  
Vol 1 (4) ◽  
pp. 377
Author(s):  
Cécile Ghouila-Houri ◽  
Ralph Sindjui ◽  
Mohammed Moutaouekkil ◽  
Omar Elmazria ◽  
Quentin Gallas ◽  
...  
Keyword(s):  
Constant Temperature ◽  
Atmospheric Pressure ◽  
Pressure Measurements ◽  
Temperature Mode

scholarly journals A Thermal Flow Sensor Based on Printed Circuit Technology in Constant Temperature Mode for Various Fluids

Sensors ◽  
2019 ◽  
Vol 19 (5) ◽  
pp. 1065 ◽  
Author(s):  
Thomas Glatzl ◽  
Roman Beigelbeck ◽  
Samir Cerimovic ◽  
Harald Steiner ◽  
Florian Wenig ◽  
...  
Keyword(s):  
Constant Temperature ◽  
Volume Flow Rate ◽  
Form Factors ◽  
Flow Sensor ◽  
Circuit Board ◽  
Thermal Flow ◽  
Fem Simulations ◽  
Printed Circuit ◽  
Thermal Flow Sensor ◽  
Temperature Mode

We present a thermal flow sensor designed for measuring air as well as water flow velocities in heating, ventilation, and air conditioning (HVAC) systems. The sensor is designed to integrate the flow along the entire diameter of the pipe also quantifying the volume flow rate of the streaming fluid where the calorimetric principle in constant temperature operation is utilized as a readout method. In the constant temperature mode, a controller keeps a specific excess temperature between sensing elements at a constant level resulting in a flow dependent heater voltage. To achieve cost-effective sensors, the fabrication of the transducer is fully based on printed circuit board technology allowing low-cost mass production with different form factors. In addition, 2D-FEM simulations were carried out in order to predict the sensor characteristic of envisaged setups. The simulation enables a fast and easy way to evaluate the sensor’s behaviour in different fluids. The results of the FEM simulations are compared to measurements in real environments, proving the credibility of the model.

Calibration of Constant-Temperature Hot-Wire Anemometers at Low Velocities in Water with Variable Fluid Temperature

1972 ◽  
Vol 94 (1) ◽  
pp. 17-22 ◽  
Author(s):  
K. Hollasch ◽  
B. Gebhart
Keyword(s):  
Experimental Study ◽  
Natural Convection ◽  
Constant Temperature ◽  
Fluid Temperature ◽  
Hot Wire ◽  
Temperature Variations ◽  
Wire Probe ◽  
Temperature Mode

Calibration of hot-wire probes operated in a constant-temperature mode in water at low velocities is discussed. Operation under circumstances where natural convection effects are important is considered. A method of calibrating a constant-temperature hot-wire probe for variations in fluid temperature is presented. The method consists of varying wire overheat during calibration at a constant fluid temperature. A relation is derived analytically relating anemometer output with a variable overheat resistance to anemometer output with fluid temperature variations. An experimental study to verify the analysis is presented.

scholarly journals Assessment of body mapping sportswear using a manikin operated in constant temperature mode and thermoregulatory model control mode

2013 ◽  
Vol 58 (7) ◽  
pp. 1673-1682 ◽  
Author(s):  
Faming Wang ◽  
Simona Del Ferraro ◽  
Vincenzo Molinaro ◽  
Matthew Morrissey ◽  
René Rossi
Keyword(s):  
Constant Temperature ◽  
Control Mode ◽  
Body Mapping ◽  
Model Control ◽  
Thermoregulatory Model ◽  
Temperature Mode

scholarly journals Analysis of various polymer parts in contact with biodiesel

2021 ◽  
Vol 2 (2) ◽  
pp. 83
Author(s):  
Miguel Moreno ◽  
Alberto Calio ◽  
Nancy Quaranta ◽  
Adrian Cristobal
Keyword(s):  
Constant Temperature ◽  
Atmospheric Pressure ◽  
Industrial Process ◽  
Polymeric Materials ◽  
Wear Characteristics ◽  
Form Part ◽  
Time Periods ◽  
Temperature And Pressure ◽  
The One

<p>In this paper, several parts consisting of polymeric materials are studied, in order to determine if they are affected when they are kept in contact with biodiesel at constant temperature and pressure. The samples used are constituted by polymers of silicone (S), acrylonitrile (AN) and propylene hexafluor (Viton-V7). These materials have been selected for investigation because they form part of an industrial process in which they are used, and have been observed early wear characteristics thereof. They consist of seals and cords which are in contact with biodiesel. These materials were kept immersed in biodiesel at atmospheric pressure at a temperature of 40°C for time periods up to 120 days. Virgins tested ones are characterized by various techniques: OM, SEM, XRD, DTA-TGA, among others. Viton sample was the least affected by treatment, while the acrylonitrile sample is the one that has shown the greatest variations.</p>

Thermal decomposition and chemism of hydronium jarosite

1987 ◽  
Vol 52 (4) ◽  
pp. 939-948 ◽  
Author(s):  
Miloslav Hartman ◽  
Václav Veselý ◽  
Karel Jakubec
Keyword(s):  
Thermal Decomposition ◽  
Reaction Time ◽  
Constant Temperature ◽  
Kinetic Equations ◽  
Spectroscopic Methods ◽  
Ferric Sulphate ◽  
Hydronium Jarosite ◽  
Thermogravimetric Data ◽  
Temperature Mode ◽  
Effects Of Temperature

A study is reported of the controlled decompositions and chemism of the technological hydronium jarosite. Chemical and spectroscopic methods were employed to determine the amounts of impurities present in jarosite. Thermogravimetric data were amassed both in the increasing and constant temperature mode. Proposed kinetic equations of Arrhenius type were tested against the results of constant temperature experiments. Differences are explored in the course of the decomposition of hydronium jarosite and that of pure ferric sulphate enneahydrate. In addition, the effects of temperature and reaction time were investigated on the amount of sulphates remaining in the calcined particles.

scholarly journals Tuning cell structure and expansion ratio of thick-walled biodegradable poly(lactic acid) foams prepared using supercritical CO2

2019 ◽  
Vol 56 (1) ◽  
pp. 89-104 ◽  
Author(s):  
Lin-Qiong Xu ◽  
Han-Xiong Huang
Keyword(s):  
Lactic Acid ◽  
Constant Temperature ◽  
Cellular Structure ◽  
Cell Structure ◽  
Expansion Ratio ◽  
Poly Lactic Acid ◽  
Time Range ◽  
Formation Mechanisms ◽  
Saturation Time ◽  
Temperature Mode

Thick-walled poly(lactic acid) samples are foamed using supercritical carbon dioxide as physical foaming agent over a wide saturation time range using a constant-temperature mode and a wide foaming pressure range using the constant-temperature mode and a varying-temperature mode. Using the constant-temperature mode, three regions with no-celled core and two regions with cells of different diameters appear on the fractured surfaces of the foamed samples prepared at 5 and 10 min saturation times, respectively, whereas a relatively uniform cellular structure is obtained at 20–180 min saturation times. Raising the foaming pressure can improve the cellular structure uniformity. Moreover, prolonging saturation time or raising foaming pressure results in rupture of more cell walls and so formation of open-celled structure to a certain extent. Using the varying-temperature mode, a bimodal cellular structure with stamen-like cells and a trimodal cellular structure with an extraordinarily high expansion ratio (76.2) are successively achieved during raising the foaming pressure (18–22 MPa). The formation mechanisms for the bimodal and trimodal cellular structures are analyzed based on the result of the foaming pressure effect on the cellular structure in the foamed poly(lactic acid) samples prepared using the constant-temperature mode.

scholarly journals The Mode of Action of Adjustable Transobturator Male System (ATOMS): Intraoperative Urethral Pressure Measurements

Uro ◽  
2021 ◽  
Vol 1 (2) ◽  
pp. 45-53
Author(s):  
Sonia Ruiz ◽  
Miguel Virseda-Chamorro ◽  
Fabian Queissert ◽  
Andrés López ◽  
Ignacio Arance ◽  
...  
Keyword(s):  
Atmospheric Pressure ◽  
Mode Of Action ◽  
Pressure Change ◽  
Urethral Pressure ◽  
Pressure Measurements ◽  
Postoperative Results ◽  
Urethral Wall ◽  
Urethral Resistance ◽  
Transobturator Mesh ◽  
Stretching Effect

(1) Background: The Adjustable Transobturator Male System (ATOMS) device is increasingly used to treat post-prostatectomy incontinence as it enhances residual urinary sphincteric function and allows continence recovery or improvement by dorsal compression of the bulbar urethra through a fixed transobturator mesh passage. The mode of action and the profile of the patients with best results are not totally understood. (2) Methods: Intraoperative urethral pressure measurements at different filling levels of the ATOMS device show increased urethral resistance and enhanced residual sphincteric activity. We evaluated whether the pattern of urethral pressure change secondary to serial progressive intraoperative filling of the cushion can predict postoperative results after ATOMS placement. (3) Results: The regression analysis showed a significant direct relationship between cushion volume and intraurethral pressure (p = 0.000). The median intraurethral pressure at atmospheric pressure was 51 ± 22.7 cm H2O, and at atmospheric pressure plus 4 mL was 80 ± 23.1 cm H2O). Cluster analyses defined a group of patients (n = 6) formed by patients with a distensible urethra and 100% continence after adjustment in contrast to another group (n = 3) with rigid urethras and 33% continence after adjustment. (4) Conclusions: As a part of its continence mechanism, the ATOMS device leads to continence by increasing intraurethral pressure owing to the stretching effect on the urethral wall caused by cushion filling that increases urethral resistance.

scholarly journals Excess molar volumes of 1,3 propanediol + (C1-C5) alkan-1-ols: Application of cubic EOS

2012 ◽  
Vol 77 (3) ◽  
pp. 363-370 ◽  
Author(s):  
Mohammad Almasi ◽  
Ladan Khosravi
Keyword(s):  
Atmospheric Pressure ◽  
Full Range ◽  
Excess Molar Volumes ◽  
Carbon Chain ◽  
Carbon Chain Length ◽  
Structural Factors ◽  
Pressure Measurements ◽  
Molar Volumes ◽  
Pure Compounds ◽  
Vibrating Tube Densimeter

Densities of the binary mixtures consist of methanol, ethanol, 1- propanol, 1-butanol and 1-pentanol with 1,3 Propanediol were measured at temperatures (293.15, 298.15, 303.15 and 313.15) K and atmospheric pressure. Measurements have been made over the full range of compositions and for the pure compounds by using a vibrating tube densimeter. Excess molar volumes have been obtained from these experimental results and were fitted to a Redlich-Kister type expansion. The results were interpreted in terms of molecular interactions and structural factors of the alcohols. It was observed that an increase of the alcohol carbon chain length led to lower interactions on mixing. The Peng-Robinson-Stryjek-Vera (PRSV) equation of state has been used to correlate the binary excess molar volumes.

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