Parshall flumes flow rate uncertainty including contributions of the model parameters and correlation effects

AbstractThe need for the estimation of the number of microbubbles (MBs) in cardiopulmonary bypass surgery has been recognized among surgeons to avoid postoperative neurological complications. MBs that exceed the diameter of human capillaries may cause endothelial disruption as well as microvascular obstructions that block posterior capillary blood flow. In this paper, we analyzed the relationship between the number of microbubbles generated and four circulation factors, i.e., intraoperative suction flow rate, venous reservoir level, continuous blood viscosity and perfusion flow rate in cardiopulmonary bypass, and proposed a neural-networked model to estimate the number of microbubbles with the factors. Model parameters were determined in a machine-learning manner using experimental data with bovine blood as the perfusate. The estimation accuracy of the model, assessed by tenfold cross-validation, demonstrated that the number of MBs can be estimated with a determinant coefficient R2 = 0.9328 (p < 0.001). A significant increase in the residual error was found when each of four factors was excluded from the contributory variables. The study demonstrated the importance of four circulation factors in the prediction of the number of MBs and its capacity to eliminate potential postsurgical complication risks.

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Experimental Verification of Real-Time Flow-Rate Estimations in a Tilting-Ladle-Type Automatic Pouring Machine

Applied Sciences ◽

10.3390/app11156701 ◽

2021 ◽

Vol 11 (15) ◽

pp. 6701

Author(s):

Yuta Sueki ◽

Yoshiyuki Noda

Keyword(s):

Real Time ◽

Molten Metal ◽

Flow Rate ◽

Kalman Filters ◽

Estimation Method ◽

Estimation Methods ◽

Liquid Volume ◽

Model Parameters ◽

Rate Estimation ◽

Time Flow

This paper discusses a real-time flow-rate estimation method for a tilting-ladle-type automatic pouring machine used in the casting industry. In most pouring machines, molten metal is poured into a mold by tilting the ladle. Precise pouring is required to improve productivity and ensure a safe pouring process. To achieve precise pouring, it is important to control the flow rate of the liquid outflow from the ladle. However, due to the high temperature of molten metal, directly measuring the flow rate to devise flow-rate feedback control is difficult. To solve this problem, specific flow-rate estimation methods have been developed. In the previous study by present authors, a simplified flow-rate estimation method was proposed, in which Kalman filters were decentralized to motor systems and the pouring process for implementing into the industrial controller of an automatic pouring machine used a complicatedly shaped ladle. The effectiveness of this flow rate estimation was verified in the experiment with the ideal condition. In the present study, the appropriateness of the real-time flow-rate estimation by decentralization of Kalman filters is verified by comparing it with two other types of existing real-time flow-rate estimations, i.e., time derivatives of the weight of the outflow liquid measured by the load cell and the liquid volume in the ladle measured by a visible camera. We especially confirmed the estimation errors of the candidate real-time flow-rate estimations in the experiments with the uncertainty of the model parameters. These flow-rate estimation methods were applied to a laboratory-type automatic pouring machine to verify their performance.

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Model-Based Analysis of Transient Behavior of Large Scale CFB Boilers

17th International Conference on Fluidized Bed Combustion ◽

10.1115/fbc2003-130 ◽

2003 ◽

Cited By ~ 3

Author(s):

Ari Kettunen ◽

Timo Hyppa¨nen ◽

Ari-Pekka Kirkinen ◽

Esa Maikkola

Keyword(s):

Flow Rate ◽

Large Scale ◽

Air Flow ◽

Model Parameters ◽

Air Flow Rate ◽

Process Data ◽

Cfb Boiler ◽

Flow Rates ◽

Load Change ◽

Secondary Air

The main objective of this study was to investigate the load change capability and effect of the individual control variables, such as fuel, primary air and secondary air flow rates, on the dynamics of large-scale CFB boilers. The dynamics of the CFB process were examined by dynamic process tests and by simulation studies. A multi-faceted set of transient process tests were performed at a commercial 235 MWe CFB unit. Fuel reactivity and interaction between gas flow rates, solid concentration profiles and heat transfer were studied by step changes of the following controllable variables: fuel feed rate, primary air flow rate, secondary air flow rate and primary to secondary air flow ratio. Load change performance was tested using two different types of tests: open and closed loop load changes. A tailored dynamic simulator for the CFB boiler was built and fine-tuned by determining the model parameters and by validating the models of each process component against measured process data of the transient test program. The know-how about the boiler dynamics obtained from the model analysis and the developed CFB simulator were utilized in designing the control systems of three new 262 MWe CFB units, which are now under construction. Further, the simulator was applied for the control system development and transient analysis of the supercritical OTU CFB boiler.

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Recycling and Extraction of Zinc Ions in Disc-Donut Column Considering Forward Mixing Mass Transfer, Chemical Reaction and Effects of Pulsed and non-Pulsed Condition

10.21203/rs.3.rs-765621/v1 ◽

2021 ◽

Author(s):

Mehdi Asadollahzadeh ◽

Rezvan Torkaman ◽

Meisam Torab-Mostaedi ◽

Mojtaba Saremi

Keyword(s):

Experimental Data ◽

Mass Transfer ◽

Flow Rate ◽

Positive Impact ◽

Plug Flow ◽

Model Parameters ◽

Zinc Ions ◽

Zinc Extraction ◽

Balance Equations ◽

Transfer Rates

Abstract The current study focuses on the recovery of zinc ions by solvent extraction in the pulsed contactor. The Zn(II) ions from chloride solution were extracted into the organic phase containing D2EHPA extractant. The resulting data were characterized for the relative amount of (a) pulsed and no-pulsed condition; and (b) flow rate of both phases. Based on the mass balance equations for the column performance description, numerical computations of mass transfer in a disc-donut column were conducted and validated the experimental data for zinc extraction. Four different models, such as plug flow, backflow, axial dispersion, and forward mixing were evaluated in this study. The results showed that the intensification of the process with the pulsed condition increased and achieved higher mass transfer rates. The forward mixing model findings based on the curve fitting approach validated well with the experimental data. The results showed that an increase in pulsation intensity, as well as the phase flow rates, have a positive impact on the performance of the extractor, whereas the enhancement of flow rate led to the reduction of the described model parameters for adverse phase.

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Fixed-Bed Column Study for the Removal of Ag(I)and Cr(III) from Aqueous Solutions Using Puffed Rice Husk

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.287-290.1620 ◽

2011 ◽

Vol 287-290 ◽

pp. 1620-1625

Author(s):

Yan Wu ◽

Zai Fang Deng ◽

Yang Tao ◽

Xue Gang Luo

Keyword(s):

Aqueous Solutions ◽

Rice Husk ◽

Flow Rate ◽

Service Time ◽

Fixed Bed ◽

Breakthrough Curves ◽

Model Parameters ◽

Column Studies ◽

Fixed Bed Column ◽

Puffed Rice

Fixed-bed column studies for the removal of Ag(Ⅰ) and Cr(Ⅲ) from individual aqueous solutions using puffed rice husk were investigated in this work. The experiments were conducted to study the effect of important column parameters such as bed height, feed flow rate and feed initial concentration of solution. It was found that increasing bed depth yielded longer service time while increase in influent concentration and flow rate resulted in faster breakthrough. Bed Depth Service Time (BDST) model was applied to analyze the experimental data and the model parameters were evaluated. Good agreement of the experimental breakthrough curves with the model predictions was observed.

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Global sensitivity analysis of the BSM2 dynamic influent disturbance scenario generator

Water Science & Technology ◽

10.2166/wst.2012.089 ◽

2012 ◽

Vol 65 (11) ◽

pp. 1912-1922 ◽

Cited By ~ 2

Author(s):

Xavier Flores-Alsina ◽

Krist V. Gernaey ◽

Ulf Jeppsson

Keyword(s):

Sensitivity Analysis ◽

Flow Rate ◽

Global Sensitivity Analysis ◽

Weather Conditions ◽

Model Parameters ◽

Rain Event ◽

Global Sensitivity ◽

Yearly Average ◽

Catchment Size ◽

Wet Weather

This paper presents the results of a global sensitivity analysis (GSA) of a phenomenological model that generates dynamic wastewater treatment plant (WWTP) influent disturbance scenarios. This influent model is part of the Benchmark Simulation Model (BSM) family and creates realistic dry/wet weather files describing diurnal, weekend and seasonal variations through the combination of different generic model blocks, i.e. households, industry, rainfall and infiltration. The GSA is carried out by combining Monte Carlo simulations and standardized regression coefficients (SRC). Cluster analysis is then applied, classifying the influence of the model parameters into strong, medium and weak. The results show that the method is able to decompose the variance of the model predictions (R2> 0.9) satisfactorily, thus identifying the model parameters with strongest impact on several flow rate descriptors calculated at different time resolutions. Catchment size (PE) and the production of wastewater per person equivalent (QperPE) are two parameters that strongly influence the yearly average dry weather flow rate and its variability. Wet weather conditions are mainly affected by three parameters: (1) the probability of occurrence of a rain event (Llrain); (2) the catchment size, incorporated in the model as a parameter representing the conversion from mm rain · day−1 to m3 · day−1 (Qpermm); and, (3) the quantity of rain falling on permeable areas (aH). The case study also shows that in both dry and wet weather conditions the SRC ranking changes when the time scale of the analysis is modified, thus demonstrating the potential to identify the effect of the model parameters on the fast/medium/slow dynamics of the flow rate. The paper ends with a discussion on the interpretation of GSA results and of the advantages of using synthetic dynamic flow rate data for WWTP influent scenario generation. This section also includes general suggestions on how to use the proposed methodology to any influent generator to adapt the created time series to a modeller's demands.

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Performance evaluation of zirconium silicate composite for removal of cadmium and zinc ions

10.21203/rs.3.rs-424230/v1 ◽

2021 ◽

Author(s):

Lamis A. Attia ◽

N.M. Sami ◽

H.S. Hassan ◽

Sayed Metwally

Keyword(s):

Flow Rate ◽

High Efficiency ◽

Sol Gel ◽

Fixed Bed ◽

Breakthrough Curves ◽

Industrial Wastes ◽

Accurate Estimation ◽

Model Parameters ◽

Column Studies ◽

Cadmium Ions

Abstract The purification of wastewater is preferred using the adsorption technique by the column due to the high efficiency of the process. The column studies are achieved to predict the removal of pollutants and clarify the adsorption capability of these pollutants in the treatment process of wastewater. Zinc and cadmium ions are presented in both radioactive and industrial wastes. Consequently, this work focused on the removal of zinc and cadmium ions from polluted wastewater using a fixed-bed column. Zirconia–silicate composite (ZrO2–SiO2) was produced using the sol-gel technique and analyzed for this purpose. Various parameters as bed depth (2, 3, and 5 cm), flow rate (2 and 3 mL/min), and initial ions concentrations (50–200 mg/L) were investigated. The column performance was computed to be 80.3 and 79.3% for Zn2+ and Cd2+, respectively, at the optimum conditions (3 cm bed depth, 2 mL/min flow rate, and 100 mg/L ions concentration). Thomas, Adams–Bohart, and Yoon–Nelson models were performed to estimate the breakthrough curves and compute the column model parameters which are valuable for process design. Thomas model presented the highest R2 values (0.84–0.97) and offered the most accurate estimation of the adsorption process.

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Flow Rate Effect on Wax Deposition Behavior in Single-Phase Laminar Flow

Journal of Energy Resources Technology ◽

10.1115/1.4041525 ◽

2018 ◽

Vol 141 (3) ◽

Cited By ~ 4

Author(s):

Pan-Sang Kang ◽

Ji Yu Hwang ◽

Jong-Se Lim

Keyword(s):

Laminar Flow ◽

Flow Rate ◽

Single Phase ◽

Measured Data ◽

Model Parameters ◽

Wax Deposition ◽

Flow Loop ◽

Deposit Thickness ◽

Depletion Effect ◽

Study Results

Wax deposition is an extremely common occurrence affecting flow assurance in oil fields. Under the laminar flow condition, the effect of the flow rate on wax deposition is still unclear. In this study, a flow loop test was conducted by considering the depletion effect to investigate the flow effect on wax deposition in single-phase laminar flow. The measured data were compared with the estimated data using models (wax deposition, hydrodynamic, and heat transfer models). The data obtained from the models were matched with the measured data; thus, thereby model parameters were tuned and the wax deposit thickness along the pipeline was estimated with respect to flow rate. The study results indicate that the wax deposit thickness decreases when the flow rate increases at the thickest spot (TS). The volume of wax deposits increases when the flow rate increases. An increase in the flow rate increases the distance between the inlet and the location of the TS.

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Model-Based Flow Rate Control with Online Model Parameters Identification in Automatic Pouring Machine

Robotics ◽

10.3390/robotics10010039 ◽

2021 ◽

Vol 10 (1) ◽

pp. 39

Author(s):

Nobutoshi Kabasawa ◽

Yoshiyuki Noda

Keyword(s):

Control System ◽

Flow Rate ◽

Rate Control ◽

Absolute Error ◽

Inverse Model ◽

Parameters Identification ◽

Working Environment ◽

Model Parameters ◽

Tilting Angle ◽

Flow Rate Control

In this study, we proposed an advanced control system for tilting-ladle-type automatic pouring machines in the casting industry. Automatic pouring machines have been introduced recently to improve the working environment of the pouring process. In the conventional study on pouring control, it has been confirmed that the pouring flow rate control contributes to improving the accuracy of the entire automatic pouring machine, such as the outflow liquid’s falling position from the ladle, the liquid’s weight filled in the mold, and the sprue cup’s liquid level. However, the conventional control system has problems: it is not easy to precisely pour the liquid in the ladle with a large tilting angle, and it takes time to adjust the control parameters. Therefore, we proposed the feedforward pouring flow rate control system, constructed by the pouring process’ inverse model with the online model parameters identification. In this approach, we derived the pouring process’ mathematical model, representing precisely the pouring process with the ladle’s large tilting angle. The model parameters in the pouring process’ inverse model in the controller are updated online via the model parameters identification. To verify the proposed pouring control system’s efficacy, we experimented using the tilting-ladle-type automatic pouring machine. In the experimental results, the mean absolute error between the outflow liquid’s weight and the reference weight was improved from 0.1346 at the first pouring to 0.0498 at the fifth pouring. Moreover, the model parameters were identified within 4 s. Therefore, it enables updating the controller’s parameters within each pouring motion interval by the proposed approach.

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Removal of Cesium from Aqueous Solution Using PAN-Based Ferrocyanide Composite Spheres: Adsorption on a Fixed-Bed Column

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.496-500.259 ◽

2014 ◽

Vol 496-500 ◽

pp. 259-263 ◽

Cited By ~ 1

Author(s):

Zhi Hui Du ◽

Ming Chun Jia ◽

Jin Feng Men

Keyword(s):

Flow Rate ◽

Fixed Bed ◽

Breakthrough Curves ◽

Model Parameters ◽

Maximum Adsorption Capacity ◽

Fixed Bed Column ◽

Composite Adsorbents ◽

Bed Height ◽

Cobalt Hexacyanoferrates ◽

Good Agreement

Two spherical composite adsorbents namely polyacrylonitrilepotassium cobalt hexacyanoferrates (PAN-KCoCF) and polyacrylonitrilepotassium nickel hexacyanoferrates (PAN-KNiCF) were synthesized. The effects of liquid flow rate, bed height and presence of other cations on the adsorption of cesium were investigated by conducting fixed-bed columns. The results showed that the column performed well at lowest flow rate for PAN-KNiCF. Flow rate examined had little influence on the adsorption of PAN-KCoCF. The breakthrough time decreased with decreasing bed height for both PAN-KCoCF and PAN-KNiCF. In addition, the existence of K+, Na+, NH4+, Ca2+and Mg2+in solution caused a reduction of maximum adsorption capacity for both of the composites. The bed depth service time (BDST) model and the Thomas model were used to analyze the experimental data and the model parameters were evaluated. Good agreement of the experimental breakthrough curves with the model predictions was observed.

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