Analysis of Pitot Tube Static Probe Angle in the Experimental Chamber Conditions

AbstractAn experimental heat treatment chamber and control system were developed to perform in-situ X-ray diffraction experiments during low-pressure carburizing (LPC) processes. Results from the experimental chamber and industrial furnace were compared, and it was proven that the built system is reliable for LPC experiments. In-situ X-ray diffraction investigations during LPC treatment were conducted at the German Electron Synchrotron Facility in Hamburg Germany. During the boost steps, carbon accumulation and carbide formation was observed at the surface. These accumulation and carbide formation decelerated the further carbon diffusion from atmosphere to the sample. In the early minutes of the diffusion steps, it is observed that cementite content continue to increase although there is no presence of gas. This effect is attributed to the high carbon accumulation at the surface during boost steps which acts as a carbon supply. During quenching, martensite at higher temperature had a lower c/a ratio than later formed ones. This difference is credited to the early transformation of austenite regions having lower carbon content. Also, it was noticed that the final carbon content dissolved in martensite reduced compared to carbon in austenite before quenching. This reduction was attributed to the auto-tempering effect.

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Spectroscopic Techniques versus Pitot Tube for the Measurement of Flow Velocity in Narrow Ducts

Sensors ◽

10.3390/s20247349 ◽

2020 ◽

Vol 20 (24) ◽

pp. 7349

Author(s):

Francesco D’Amato ◽

Silvia Viciani ◽

Alessio Montori ◽

Marco Barucci ◽

Carmen Morreale ◽

...

Keyword(s):

Flow Field ◽

Flow Velocity ◽

Pitot Tube ◽

Optical Measurements ◽

Trace Gas ◽

Dual Function ◽

Spectroscopic Techniques ◽

Gas Composition ◽

Flow Conditions ◽

Theoretical Simulation

In order to assess the limits and applicability of Pitot tubes for the measurement of flow velocity in narrow ducts, e.g., biomass burning plants, an optical, dual function device was implemented. This sensor, based on spectroscopic techniques, targets a trace gas, injected inside the stack either in bursts, or continuously, so performing transit time or dilution measurements. A comparison of the two optical techniques with respect to Pitot readings was carried out in different flow conditions (speed, temperature, gas composition). The results of the two optical measurements are in agreement with each other and fit quite well the theoretical simulation of the flow field, while the results of the Pitot measurements show a remarkable dependence on position and inclination of the Pitot tube with respect to the duct axis. The implications for the metrology of small combustors’ emissions are outlined.

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Analysis of Pitot tube Airflow Velocity Sensor Behavior in Blockage Situations

2020 IEEE Sensors ◽

10.1109/sensors47125.2020.9278790 ◽

2020 ◽

Author(s):

Ata Golparvar ◽

Murat Kaya Yapici

Keyword(s):

Pitot Tube ◽

Airflow Velocity ◽

Velocity Sensor

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CFD Simulation of Particle Transport and Dispersion in Indoor Environment by Human Walking

Volume 1: Symposia, Parts A and B ◽

10.1115/fedsm2012-72149 ◽

2012 ◽

Cited By ~ 1

Author(s):

Iman Goldasteh ◽

Goodarz Ahmadi ◽

Andrea Ferro

Keyword(s):

Particulate Matter ◽

High Speed ◽

Cfd Simulation ◽

Three Dimensional ◽

Study Data ◽

Turbulent Dispersion ◽

Experimental Chamber ◽

Indoor Environments ◽

Three Dimensional Model ◽

Particle Resuspension

Particle resuspension is an important source of particulate matter in indoor environments that significantly affects the indoor air quality and could potentially have adverse effect on human health. Earlier efforts to investigate indoor particle resuspension hypothesized that high speed airflow generated at the floor level during the gate cycle is the main cause of particle resuspension. The resuspended particles are then assumed to be dispersed by the airflow in the room, which is impacted by both the ventilation and the occupant movement, leading to increased PM concentration. In this study, a three dimensional model of a room was developed using FLUENT™ CFD package. A RANS approach with the RNG k-ε turbulence model was used for simulating the airflow field in the room for different ventilation conditions. The trajectories of resuspended particulate matter were computed with a Lagrangian method by solving the equations of particle motion. The effect of turbulent dispersion was included with the use of the eddy lifetime model. The resuspension of particles due to gait cycle was estimated and included in the computational model. The dispersion and transport of particles resuspended from flooring as well as particle re-deposition on flooring and walls were simulated. Particle concentrations in the room generated by the resuspension process were evaluated and the results were compared with experimental chamber study data as well as simplified model predictions, and good agreement was found.

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Calibration of a new experimental chamber for PIXE analysis at the Accelerator Facilities Division of Atomic Energy Centre Dhaka (AECD)

Nuclear Instruments and Methods in Physics Research Section A Accelerators Spectrometers Detectors and Associated Equipment ◽

10.1016/j.nima.2015.01.090 ◽

2015 ◽

Vol 781 ◽

pp. 39-43 ◽

Cited By ~ 1

Author(s):

Md. Taufique Hassan ◽

Md. Asad Shariff ◽

Amzad Hossein ◽

Md. Joynal Abedin ◽

A.K.M. Fazlul Hoque ◽

...

Keyword(s):

Atomic Energy ◽

Experimental Chamber ◽

Pixe Analysis

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Analysis of pulsating flow measurement of engine exhaust by a Pitot tube flowmeter

International Journal of Engine Research ◽

10.1243/146808705x7329 ◽

2005 ◽

Vol 6 (1) ◽

pp. 85-93 ◽

Cited By ~ 12

Author(s):

H Nakamura ◽

I Asano ◽

M Adachi ◽

J Senda

Keyword(s):

Fast Response ◽

Differential Pressure ◽

Pulsating Flow ◽

Pitot Tube ◽

Engine Exhaust ◽

Idle Speed ◽

Pressure Transducers ◽

Vehicle Engine ◽

Before And After ◽

Response Pressure

The Pitot tube flowmetering technique has been used to measure pulsating flow from a vehicle engine exhaust. In general, flowmetering techniques that utilize differential pressure measurements based on Bernoulli's theory are likely to show erroneous readings when measuring an average flowrate of pulsating flow. The primary reason for this is the non-linear relationship between the differential pressure and the flowrate; i.e. the flowrate is proportional to the square root of the differential pressure. Therefore, an average of the differential pressure does not give an average of pulsating flow. In this study, fast response pressure transducers have been used to measure the pulsating pressure. Then the pulsating differential pressure is converted to the flowrate while keeping the pulsation unaveraged. An average flowrate is then calculated in the flowrate domain in order to maintain linearity before and after averaging. The peak amplitude of a pulsation measured here was about 1800 L/min at an average flowrate of 70 L/min when the engine ran at idle speed. This measurement has been confirmed by measuring the pulsation with a gas analyser. The results show a large amount of back and forth gas movement in the exhaust tube. This magnitude of pulsation can cause as much as five times higher erroneous results with the pressure domain averaging when compared to a flowrate domain averaging.

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