Effect of dynamic bias on accuracy of radioactive particle tracking (RPT) technique at different data acquisition frequencies

Kamalanathan, Premkumar; Kalo, Lipika; Pant, H.J.; Upadhyay, R. K.

doi:10.1016/j.apradiso.2017.06.034

Cited by 6 publications

(5 citation statements)

References 20 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…29,36 The detector arrangement, which yielded maximum values of resolution and sensitivity, is considered for the measurements. The data is acquired 37 with a 100 Hz frequency for around 5 days continuously to get sufficient statistics. Prior to the main experiment, calibration is performed to determine the relationship between the photon count detected on each detector and the distance between the tracer particle and each detector.…”

Section: Experimental Setup and Measurement Techniquementioning

confidence: 99%

“…The values of resolution and sensitivity are calculated for different detector positionings. , The detector arrangement, which yielded maximum values of resolution and sensitivity, is considered for the measurements. The data is acquired with a 100 Hz frequency for around 5 days continuously to get sufficient statistics. Prior to the main experiment, calibration is performed to determine the relationship between the photon count detected on each detector and the distance between the tracer particle and each detector. ,,− For calibration, the tracer particle is pasted on the tip of a pointed needle of a 6 mm-diameter threaded rod.…”

Section: Experimental Setup and Measurement Techniquementioning

confidence: 99%

See 1 more Smart Citation

Measurements of Solid Velocity in a Pilot-Scale Geldart’s Group B Circulating Fluidized Bed Using a Radioactive Particle Tracking Technique

Tribedi

Pillajetti

Kumari

et al. 2022

Ind. Eng. Chem. Res.

View full text Add to dashboard Cite

Circulating fluidized bed (CFB) is used for a wide range of gas−solid reactions. However, most of the data reported on CFBs are for Geldart's group A particles, although the applications of Geldart's group B CFBs are numerous. In the current work, the solid flow field is deciphered in a pilot-plant-scale Geldart's group B CFB riser. Solid motion is tracked by using a radioactive particle tracking technique. The data are reported in a fully developed flow region of 0.1 m diameter and 6.5 m height CFB riser at different inlet gas velocities (7.6−9.2 m/s) and solid fluxes (100−200 kg/m 2 s). The different flow quantities such as mean axial and radial velocities, rootmean-square velocities, granular temperature, and turbulent intensities are calculated for all the cases. It is observed that solid motion predominantly lies in the axial direction. The probability distribution function of instantaneous solid velocity shows wider distribution near the wall as compared to the center of the riser. This shows that the probability of mesoscale metastable structure formation increases while moving from the center to the wall. Furthermore, the results show that the mean solid velocity largely depends on gas−solid interactions. However, for the fluctuating velocity, both gas−solid and solid−solid interactions are critical. The results indicate that the solid turbulent intensity in Geldart's group B riser is significantly higher than that in the group A riser. Hence, solid velocity fluctuations are higher in the group B riser.

show abstract

Section: Experimental Setup and Measurement Techniquementioning

confidence: 99%

Section: Experimental Setup and Measurement Techniquementioning

confidence: 99%

Measurements of Solid Velocity in a Pilot-Scale Geldart’s Group B Circulating Fluidized Bed Using a Radioactive Particle Tracking Technique

Tribedi

Pillajetti

Kumari

et al. 2022

Ind. Eng. Chem. Res.

View full text Add to dashboard Cite

show abstract

“…The full potential of PEPT to measure dynamic particle behaviour in turbulent gas-liquid-solid multiphase flows, such as flotation, is still in progress and requires a number of technical advances to achieve higher resolution. Particular challenges to overcome are a dynamic bias arising from the mode of determining the tracer location [58], the development of suitable tracer particles (both small size and high activity for high speed tracking) [38] and the varying density of the media, with high density regions attenuating the gamma radiation measured by PEPT, and low density regions near the froth phase leading to an increase in positron range. All these factors tend to increase the uncertainty in the measurements of particle motion.…”

Section: Discussionmentioning

confidence: 99%

Characterisation of solid hydrodynamics in a three-phase stirred tank reactor with positron emission particle tracking (PEPT)

Cole

Brito-Parada

Hadler

et al. 2022

Chemical Engineering Journal

View full text Add to dashboard Cite

“…The counts recorded on each detector is used to locate the instantaneous tracer particle position time series. The same is used to calculate instantaneous velocities, mean velocities, axial and radial rms velocities, turbulent kinetic energy, and turbulent intensity by the suitable postprocessing, which is explained in detail in our previous contributions. − Postprocessing variables are shown in Table .…”

Section: Experimental Setup and Techniquementioning

confidence: 99%

“…Though the technique requires the use of radioactivity, this technique is robust and can be deployed at any scale with the same fidelity as it does not need a transparent column. Due to these advantages, several studies implemented RPT to obtain the local flow field in a variety of reactors/contactors. − Though some studies are available on the experimental investigation of local hydrodynamic using PIV, LDA, and optical fiber probe-in PDDC, , as well as in the pulse column with downcomers, the local hydrodynamics in the pulsed sieve plate column without downcomers is not investigated so far. Further, no information on the use of RPT in a pulsed sieve column, where the motion is primarily because of pulsation, is reported yet.…”

Section: Introductionmentioning

confidence: 99%

Investigation of Velocity Field Inside a Single-Phase Pulsed Sieve Plate Column Using Radioactive Particle Tracking

Pillajetti

Gupta

Goswami

et al. 2022

Ind. Eng. Chem. Res.

View full text Add to dashboard Cite

Pulsed sieved plate columns (PSPCs) are used for liquid–liquid extraction processes in several industries such as mineral processing, pharmaceuticals, and nuclear fuel cycle. Despite their widespread use in the industry, there is a dearth of experimental insights into the local hydrodynamics in PSPC. This work for the first time reports the local hydrodynamics inside a PSPC using the radioactive particle tracking technique. Local instantaneous velocity, mean velocity, turbulent quantities such as root-mean square (rms) velocity, turbulent kinetic energy, and turbulent intensity are measured through the radioactive particle tracking technique. The effects of pulsing velocity and liquid flow rate on local hydrodynamics and turbulence parameters are studied for no net flow and single-phase flow conditions. Results indicate that the mean flow velocity is low; however, significant fluctuating velocity components are generated due to the pulsing action. Though the fluctuations in the axial direction dominate, significant radial velocity is observed in all of the cases. Further, results show that the fluctuations in the axial direction attenuate in the case of single-phase flow when compared with the no flow condition. This leads to lower axial rms velocity, turbulent kinetic energy, and turbulent intensity in the case of single-phase flow as compared with the no flow condition. In all of the cases, significant fluctuations are observed, which signify a higher degree of mixing and hence enhanced mass transfer in PSPCs.

show abstract

Effect of dynamic bias on accuracy of radioactive particle tracking (RPT) technique at different data acquisition frequencies

Cited by 6 publications

References 20 publications

Measurements of Solid Velocity in a Pilot-Scale Geldart’s Group B Circulating Fluidized Bed Using a Radioactive Particle Tracking Technique

Measurements of Solid Velocity in a Pilot-Scale Geldart’s Group B Circulating Fluidized Bed Using a Radioactive Particle Tracking Technique

Characterisation of solid hydrodynamics in a three-phase stirred tank reactor with positron emission particle tracking (PEPT)

Investigation of Velocity Field Inside a Single-Phase Pulsed Sieve Plate Column Using Radioactive Particle Tracking

Contact Info

Product

Resources

About