Статті в журналах: "Flowrate control"

1

Avila, Raudel, Yixin Wu, Rinaldo Garziera, John A. Rogers, and Yonggang Huang. "Analytical Modeling of Flowrate and Its Maxima in Electrochemical Bioelectronics with Drug Delivery Capabilities." Research 2022 (March 4, 2022): 1–13. http://dx.doi.org/10.34133/2022/9805932.

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Flowrate control in flexible bioelectronics with targeted drug delivery capabilities is essential to ensure timely and safe delivery. For neuroscience and pharmacogenetics studies in small animals, these flexible bioelectronic systems can be tailored to deliver small drug volumes on a controlled fashion without damaging surrounding tissues from stresses induced by excessively high flowrates. The drug delivery process is realized by an electrochemical reaction that pressurizes the internal bioelectronic chambers to deform a flexible polymer membrane that pumps the drug through a network of microchannels implanted in the small animal. The flowrate temporal profile and global maximum are governed and can be modeled by the ideal gas law. Here, we obtain an analytical solution that groups the relevant mechanical, fluidic, environmental, and electrochemical terms involved in the drug delivery process into a set of three nondimensional parameters. The unique combinations of these three nondimensional parameters (related to the initial pressure, initial gas volume, and microfluidic resistance) can be used to model the flowrate and scale up the flexible bioelectronic design for experiments in medium and large animal models. The analytical solution is divided into (1) a fast variable that controls the maximum flowrate and (2) a slow variable that models the temporal profile. Together, the two variables detail the complete drug delivery process and control using the three nondimensional parameters. Comparison of the analytical model with alternative numerical models shows excellent agreement and validates the analytic modeling approach. These findings serve as a theoretical framework to design and optimize future flexible bioelectronic systems used in biomedical research, or related medical fields, and analytically control the flowrate and its global maximum for successful drug delivery.

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2

HABIB, ROBERT SH, and QAIS A. H. ALNOUMAN. "Microcomputer-based liquid flowrate control system." International Journal of Electronics 65, no. 1 (July 1988): 117–25. http://dx.doi.org/10.1080/00207218808945210.

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3

Li, Dong, Jie Hang, Yunhua Li, and Sujun Dong. "Fuel Flowrate Control for Aeroengine and Fuel Thermal Management for Airborne System of Aircraft—An Overview." Applied Sciences 12, no. 1 (December 28, 2021): 279. http://dx.doi.org/10.3390/app12010279.

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Fuel flowrate control system and fuel thermal management are very important for aeroengine and the overall aircraft, and it has been researched for several decades. This survey paper makes a comprehensive and systematic overview on the exiting fuel flowrate regulation methods, thermal load of fuel metering units, fuel-based thermal management, and the fuel tank’s thermal management topology network with drain and recirculation. This paper firstly reviews the mechanism, technical advantages, and technical challenges of the fuel metering unit with flowrate control valve and constant pressure difference valve compensator, flowrate control valve and variable displacement pump-based pressure difference compensator, and motor-based flowrate regulation. Then, the technical characteristics of above fuel flowrate control methods related to thermal management are discussed and compared. Meanwhile, the behaviors of recirculated fuel flow within single tank system and dual tank system are explored. Thirdly, the paper discusses the future directions of fuel flowrate control and thermal management. The survey is significant to the fuel flowrate control and fuel thermal management of the aircraft.

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4

Shen, Hai-Feng, Xin-Jian Zhu, Meng Shao, and Hong-fei Cao. "Neural Network Predictive Control for Vanadium Redox Flow Battery." Journal of Applied Mathematics 2013 (2013): 1–7. http://dx.doi.org/10.1155/2013/538237.

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The vanadium redox flow battery (VRB) is a nonlinear system with unknown dynamics and disturbances. The flowrate of the electrolyte is an important control mechanism in the operation of a VRB system. Too low or too high flowrate is unfavorable for the safety and performance of VRB. This paper presents a neural network predictive control scheme to enhance the overall performance of the battery. A radial basis function (RBF) network is employed to approximate the dynamics of the VRB system. The genetic algorithm (GA) is used to obtain the optimum initial values of the RBF network parameters. The gradient descent algorithm is used to optimize the objective function of the predictive controller. Compared with the constant flowrate, the simulation results show that the flowrate optimized by neural network predictive controller can increase the power delivered by the battery during the discharge and decrease the power consumed during the charge.

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5

Mao, Yucai, Yunxiang Wang, Lei Zhang, and Qiuju Guo. "A HUMIDITY CONTROL TECHNIQUE BASED ON NAFION MEMBRANE AND ITS APPLICATION ON THE EVALUATION OF HUMIDITY RESPONSE FOR RADON MONITOR." Radiation Protection Dosimetry 184, no. 3-4 (April 26, 2019): 448–52. http://dx.doi.org/10.1093/rpd/ncz083.

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Abstract Electrostatic collection technique is widely used in various radon monitors. The mechanism of this kind of radon monitor is that the positive Po particles, produced by decay of radon, can be collected on the surface of detector in electric field. Collection efficiency, therefore, could be affected by air humidity. Calibration under different humidity conditions or test of humidity response is necessary consequently. In this study, a humidity control technique based on Nafion membrane tube (NMT) is developed. Under a consistent flowrate with a certain stable level of radon concentration and humidity of main-path inlet, the humidity of outlet sample gas from the main-path can be adjusted and stably controlled at a certain level by changing side-path’s flowrates of NMT. By adjusting main and side-path flowrate, RH of outlet gas of the main-path can be controlled from 5.3 to 80.0%. Theoretical study were also performed. Based on this, humidity influence calibration of an electrostatic radon monitor was performed, and a relationship between the sensitivity of the radon monitor and relative humidity was obtained.

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6

Amanowicz, Łukasz. "Controlling the Thermal Power of a Wall Heating Panel with Heat Pipes by Changing the Mass Flowrate and Temperature of Supplying Water—Experimental Investigations." Energies 13, no. 24 (December 11, 2020): 6547. http://dx.doi.org/10.3390/en13246547.

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Renewable energy sources for the purpose of heating buildings cooperate perfectly with so-called low-temperature heating systems. Water loop surface heating systems had been thoroughly tested. In contrast, thermal performance of wall panels with heat pipes have not been fully recognized, yet. The determination of the thermal power as well as the control of panels thermal performance cannot be performed with the methods developed for water loop systems. In this paper, the novel heating panels with heat pipes were tested to analyze the possibility of controlling their performance by changing the mass flowrate of heating water and its temperature. Specific heating power of the investigated panels varies from 16.9 W/m2 to 93.8 W/m2 when supplying a water temperature ranging from 35 °C to 65 °C and mass flowrate from 10 g/s to 47.5 g/s. Investigations revealed that the thermal performance of the panels is more sensitive to the changes of temperature than to the changes of mass flowrate of supplying water, and thus, should be controlled by changing the supply water temperature at low mass flowrates to obtain a low energy usage of pumps (diminished pressure losses) and good quality of controlling.

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7

Zhou, Su, Jie Jin, and Yuehua Wei. "Research on Online Diagnosis Method of Fuel Cell Centrifugal Air Compressor Surge Fault." Energies 14, no. 11 (May 25, 2021): 3071. http://dx.doi.org/10.3390/en14113071.

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Stable operation of fuel cell air compressions is constrained by rotating surge in low flowrate conditions. In this paper, a diagnosis criterion based on wavelet transform to solve the surge fault is proposed. First of all, the Fourier transform was used to analyze the spectral characteristics of the outlet flowrate. Before wavelet transform was used, the data are standardized. This step eliminated the influence of the flowrate’s absolute value. Then, the wavelet coefficients under characteristic frequencies were extracted. Finally, the diagnosis criterion’s threshold, which indicates the surge occurrence, was defined from the perspective of safety margin. The criterion threshold alerted a surge only 1 s after it occurred. The analysis results show that the criterion meets with the expectation, and it can be used for the control of anti-surge valve.

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8

Park, K., J. Kim, S. K. Kauh, S. T. Ro, and J. Lee. "Measurement of air flowrate by using an integration type ultrasonic flow meter applicable for spark ignition engine control." Proceedings of the Institution of Mechanical Engineers, Part D: Journal of Automobile Engineering 211, no. 2 (February 1, 1997): 129–35. http://dx.doi.org/10.1243/0954407971526290.

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An integration type air flow meter (IFM), composed of an ultrasonic sensor with an integration circuit, is tested for the air flowrate measurement in a pulsating flow condition. An accurate air flowrate measurement is essential to control the fuel injection rate of a fuel injection spark ignition (SI) engine. The difficulty comes from the pulsating and reverse flow characteristics of the induction pipe. The IFM integrates the instantaneous flowrate signal during the quarter cycle corresponding to an intake period of a four-stroke four-cylinder engine in order to identify and account for the flow direction. The IFM has significantly improved the accuracy of flowrate measurement compared with a hot wire type flow meter in certain conditions where a flow reversal exists. The sampling method is also easier when using the IFM compared with other techniques.

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9

Soave, Nicolò, and Massimiliano Barolo. "On the Effectiveness of Heat-Exchanger Bypass Control." Processes 9, no. 2 (January 28, 2021): 244. http://dx.doi.org/10.3390/pr9020244.

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In heat exchangers with bypassing, a fraction of the flowrate of one fluid (typically the one whose temperature needs to be controlled tightly) bypasses the exchanger and mixes right after the exchanger outlet with the fraction flowing through the exchanger. The advantages of this configuration are long known. Among them, the most significant is that it can improve heat-transfer control because the temperature dynamics is significantly faster than in a standard heat-exchanger configuration. Additionally, it can increase the rangeability of the process wherein the heat exchanger operates. Existing rules of thumb do not provide univocal indications for assigning the design bypass flowrate. In this study, using a simple graphical representation of steady-state heat and mass balances originally proposed for conventional heat-exchanger design, we clarify why and under which design conditions bypass control can be effective. Increased rangeability results from the fact that the heat-exchanger steady-state gain can be assigned by design when a bypass configuration is used, whereas it typically cannot in a conventional heat exchanger. The design bypass flowrate should therefore be assigned so as to make the heat exchanger operate in a region where the steady-state gain is relatively high (and constant).

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10

Peng, Guangzheng, and Tong Zhao. "A Dynamic Evaluation Technique for Liquid Flow Meters Based on Hydraulic Line Dynamics." Journal of Dynamic Systems, Measurement, and Control 119, no. 2 (June 1, 1997): 305–7. http://dx.doi.org/10.1115/1.2801252.

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A new concept for the evaluation of flowmeter dynamic response is presented. A technique based on hydraulic line dynamics is applied to achieve accurate measurements of the reference flowrate. The major components in the equipment used in experimental verification of the theory were a test pipe, a pulsating flow generator, three pressure transducers, an A/D converter, and a microcomputer system. This equipment allowed the dynamic characteristics of a flowmeter to be investigated in both the time and frequency domains. Comparisons of flowrates measured using the line dynamic technique and the same flowrates recorded by the flowmeter are presented. The results confirm the feasibility and practicability of the dynamic line technique for measuring rapidly varying flows.

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11

Saediamiri, Meghdad, and Madjid Birouk. "New solid particle seeding generator for laser-based velocity measurements in reacting flows." Transactions of the Canadian Society for Mechanical Engineering 43, no. 1 (March 1, 2019): 63–68. http://dx.doi.org/10.1139/tcsme-2017-0058.

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The design of a new solid particle seeding generator for laser-based velocity measurements in gaseous flows is reported. Performance tests revealed that the new seeder has the ability to control the concentration of seeding particles in a flow independently of the flowrate. It also can provide a steady supply of seeding particles, operate over an extended range of flowrate, and break up agglomerates into smaller particles. These features give this seeder advantages over its counterparts, especially at low volumetric flowrate.

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12

Fuladgar, Amir, and Zoha Vatani. "New empirical correlation for oil flowrate prediction through chokes." Journal of the Serbian Chemical Society 85, no. 5 (2020): 687–96. http://dx.doi.org/10.2298/jsc190520110f.

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Accurate prediction of choke restricted multiphase flowrate is always interesting in oil industry in the absence of flowmeters for field production monitoring and management purposes. Also, in a producing well, choke is installed for controlling the production rate. In this research, new correlation is developed for predicting the multiphase flowrate through choke specified for one of the Iranian southern oilfields. For this purpose, 166 sets of flowrate measurement data, was gathered and filtered to 142 data sets, at the quality control step. This data was regressed to a linearized modified correlation between the measured flowrate, the wellhead pressure choke size and the producing gas liquid ratio to find the best set of correlation parameters. The resulted correlation was evaluated by determining its average relative error and root mean square error by the excluded set of test data. The evaluation indicated that new correlation could significantly improve the accuracy of flowrate predictions in contrast to previous prominent correlations.

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13

Pécora, Araí A. B., Leonardo Goldstein, Geraldo Lombardi, and Josmar D. Pagliuso. "New particulate solids pneumatic feeding device with mass flowrate control." Powder Technology 79, no. 3 (June 1994): 265–68. http://dx.doi.org/10.1016/0032-5910(94)02827-3.

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14

KUROKAWA, Junichi, Kenji IDO, and Hiromichi TAKAHASHI. "Feed-Forward Control of Pressure and Flowrate in Pumping System." Transactions of the Japan Society of Mechanical Engineers Series B 57, no. 537 (1991): 1707–11. http://dx.doi.org/10.1299/kikaib.57.1707.

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15

Avila, Raudel, Chenhang Li, Yeguang Xue, John A. Rogers, and Yonggang Huang. "Modeling programmable drug delivery in bioelectronics with electrochemical actuation." Proceedings of the National Academy of Sciences 118, no. 11 (March 8, 2021): e2026405118. http://dx.doi.org/10.1073/pnas.2026405118.

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Drug delivery systems featuring electrochemical actuation represent an emerging class of biomedical technology with programmable volume/flowrate capabilities for localized delivery. Recent work establishes applications in neuroscience experiments involving small animals in the context of pharmacological response. However, for programmable delivery, the available flowrate control and delivery time models fail to consider key variables of the drug delivery system––microfluidic resistance and membrane stiffness. Here we establish an analytical model that accounts for the missing variables and provides a scalable understanding of each variable influence in the physics of delivery process (i.e., maximum flowrate, delivery time). This analytical model accounts for the key parameters––initial environmental pressure, initial volume, microfluidic resistance, flexible membrane, current, and temperature––to control the delivery and bypasses numerical simulations allowing faster system optimization for different in vivo experiments. We show that the delivery process is controlled by three nondimensional parameters, and the volume/flowrate results from the proposed analytical model agree with the numerical results and experiments. These results have relevance to the many emerging applications of programmable delivery in clinical studies within the neuroscience and broader biomedical communities.

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16

Jeon, Seok-Yun, Joon-Yong Yoon, and Choon-Man Jang. "Bubble Size and Bubble Concentration of a Microbubble Pump with Respect to Operating Conditions." Energies 11, no. 7 (July 17, 2018): 1864. http://dx.doi.org/10.3390/en11071864.

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The present paper describes some aspects of the bubble size and concentration of a microbubble pump with respect to flow and pressure conditions. The microbubble pump used in the present study has an open channel impeller of a regenerative pump, which generates micro-sized bubbles with the rotation of the impeller. The bubble characteristics are analyzed by measuring the bubble size and concentration using the experimental apparatus consisting of open-loop facilities; a regenerative pump, a particle counter, electronic flow meters, pressure sensors, flow control valves, a torque meter, and reservoir tanks. To control the intake, and the air flowrate upstream of the pump, a high precision flow control valve is introduced. The bubble characteristics have been analyzed by controlling the intake air flowrate and the pressure difference of the pump while the rotational frequency of the pump impeller was kept constant. All measurement data was stored on the computer through the NI (National Instrument) interface system. The bubble size and concentration are mainly affected by three operating parameters: the intake air flowrate, the pressure difference, and the water flowrate supplied to the pump. It is noted that the operating conditions that can most effectively generate microbubbles in the range of 20 to 30 micrometers are at the pressure of 5 bar and at the air flowrate ratio of 4.0 percent for the present pump. Throughout the experimental measurements, it was found that the pump efficiency changed by less than 1.2 percent, depending on the intake air supply. The performance characteristics of microbubble generation obtained by experimental measurements are analyzed and discussed in detail.

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17

Pečar, Borut, Danilo Vrtačnik, Matic Pavlin, and Matej Možek. "A Rapid Prototyped Thermal Mass Flowmeter." Sensors 21, no. 16 (August 9, 2021): 5373. http://dx.doi.org/10.3390/s21165373.

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An innovative rapid prototyping technique for embedding microcomponents in PDMS replicas was developed and applied on a thermal mass flowmeter for closed loop micropump flowrate control. Crucial flowmeter design and thermal parameters were investigated with a 3-D fully coupled electro-thermal-fluidic model which was built in Comsol Multiphysics 5.2. The flowmeter was characterized for three distinct measuring configurations. For precise low flowrate applications, a sensor-heater-sensor flowmeter configuration with a constant heater temperature was found to be the most appropriate yielding the measuring range of 0 to 90 µL·min−1 and the sensitivity of 1.3 °C·µL−1·min in the lower flowrate range of 0 to 40 µL·min−1.

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18

Adib, Ali Asghari, and David J. Hoelzle. "Hybrid Control of Flowrate in Microextrusion-Based Direct-Write Additive Manufacturing." IEEE Control Systems Letters 6 (2022): 97–102. http://dx.doi.org/10.1109/lcsys.2021.3049897.

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19

Hermawan, Yulius Deddy. "Design of Flow Control System with A Kickback Flow as A Manipulated Variable." Eksergi 14, no. 2 (December 31, 2017): 23. http://dx.doi.org/10.31315/e.v14i2.2089.

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The open loop experiment of water flow dynamic in pipe has been done in laboratory. Pump was used to flow water in pipe. Part of liquid from discard of pump was recycled back to the suction of pump (kickback) and adjusted to control the liquid flow to the next process. The open loop laboratory experiment produced the steady state parameters; they were discard flowrate =16.6 [L/min], kickback flowrate =5.8 [L/min], and liquid flowrate to the next process =10.8 [L/min]. These steady state parameters were then used as the initial value for closed loop simulation with computer programming. This study has proposed the liquid flow control configuration by manipulating the kickback flow. Proportional Integral (PI) was proposed to control the flow and Routh-Hurwitz (RH) stability criterion was chosen to predict the range of the controller gain (Kc) that gives stable response. The closed loop model was solved analytically with Laplace method for both servo and regulatory problems. The set point change of flow and disturbance were made based on step function. The scilab software was used to do closed loop simulation. Based on RH stability criterion, the controller gain should be negative in order to give stable response. The closed loop simulation showed that by using controller gain Kc=–0.5 and integral time constant tI=0.3 [min], stable and fast response with Integral Absolute Error (IAE) near to zero (0,0022) could be achieved.

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20

Meyer, J. W., and J. H. Bonin. "Performance and Flowrate Control of the Kinetic Extruder Coal Powder Pump." Journal of Engineering for Gas Turbines and Power 107, no. 3 (July 1, 1985): 652–60. http://dx.doi.org/10.1115/1.3239785.

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The kinetic extruder is a novel centrifugal machine for feeding powdered material, in particular coal, against gas back pressure. The nonmechanical method of flow-rate control in the machine is described. Performance data obtained in tests of the kinetic extruder are presented and compared with theoretical predictions. It is found that a one-dimensional model of the material flow through the device gives accurate predictions of most aspects of the machine’s performance. However, some details of the limiting behavior evidently require a more refined analysis.

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21

Ahmad, Saleh. "Model Predictive Control for the Flowrate Control Loop of the FESTO MPS PA Compact Workstation." Journal of Hunan University Natural Sciences 49, no. 1 (January 28, 2022): 179–85. http://dx.doi.org/10.55463/issn.1674-2974.49.1.23.

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Model Predictive Control techniques offer favorable characteristics for the process control sector and have been used in industry since the 1980s. Some of the advantages of the Model Predictive Control techniques are that the process model can capture both static and dynamic interactions between input, output, and disturbance variables; the existing constraints on inputs and outputs are considered systematically, and the control calculations can be coordinated with the calculation of optimum set-points. This study aims to design and implement a Model Predictive controller for the flowrate control loop of the FESTO MPS PA Compact Workstation. The designed Model Predictive controller has an important advantage because it is easy to conFig. how much energy should be used using well-designed tuning parameters. First, a dynamic model of the plant is obtained using Pseudo-Random Binary Signal input. The obtained model is used to define the objective function, determine the aspects to be optimized and analyze and identify the restrictions and limitations of the control algorithm. For the implementation of the model predictive control algorithm, LabVIEW software was used because it can execute a graphic visualization of the operation of the plant, and it offers ActiveX controls that are needed for interfacing with the MPS PA compact workstation. Finally, the controller's behavior was analyzed, and comments about the obtained results and conclusions on this line of research are presented.

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22

Le, T. T., J. Watton, and D. T. Pham. "An artificial neural network based approach to fault diagnosis and classification of fluid power systems." Proceedings of the Institution of Mechanical Engineers, Part I: Journal of Systems and Control Engineering 211, no. 4 (June 1, 1997): 307–17. http://dx.doi.org/10.1243/0959651971539830.

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In this paper, multilayer perceptron (MLP) type neural networks are used to detect leakages in an electrohydraulic cylinder drive. Both single-leakage and multiple-leakage type faults are investigated. The performance of MLPs is examined relating to the level of leakage flowrate and it was found that MLPs perform well for line leakages but for across-cylinder seal leakages they could only detect leakage over 1.01/min. The generalization tests on non-training leakage flowrate and working temperature are also included. A novel feature is the use of system state variables for network training, including additional terms to accelerate convergence. The approach has also made a significant contribution to multiple-fault detection, particularly for the complex three-fault case.

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23

Harrell, R. C., G. A. Kranzler, and C. S. Hsu. "Adaptive Control of the Fluid Heat Exchange Process." Journal of Dynamic Systems, Measurement, and Control 109, no. 1 (March 1, 1987): 49–52. http://dx.doi.org/10.1115/1.3143819.

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An adaptive algorithm for controlling the fluid heat exchange process via flowrate manipulation was presented. The algorithm utilized a model reference structure based on a linear time-variant approximation of the bilinear process dynamics. Adaptive feedforward and feedback compensation was provided. The control law was implemented on an evacuated tube solar water heating system. Experimental results demonstrated the ability of the adaptive scheme to accurately control collector fluid temperature under severe variations in solar insolation.

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24

Höfling, Thomas, Rüdiger Deibert, and Oliver Hecker. "Fault Detection of Flowrate and Temperature Control Loops using Estimated Parity Equations." IFAC Proceedings Volumes 28, no. 12 (June 1995): 193–98. http://dx.doi.org/10.1016/s1474-6670(17)45421-8.

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25

Keitaanniemi, O., T. Kujansivu, and A. Kaunonen. "Retention Measurement in Paper Machines and its Control Using Retention Aid Flowrate." IFAC Proceedings Volumes 20, no. 13 (October 1987): 85–92. http://dx.doi.org/10.1016/s1474-6670(17)55569-x.

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26

KOGAN, A., I. HODARA, and M. VANA. "Steam flowrate to solar cavity reactor—a simple measurement and control method." International Journal of Hydrogen Energy 16, no. 8 (1991): 531–34. http://dx.doi.org/10.1016/0360-3199(91)90151-8.

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27

Fitzpatrick, John, Franck Gloanec, Elisa Michel, Johanna Blondy, and Anais Lauzeral. "Application of Mathematical Modelling to Reducing and Minimising Energy Requirement for Oxygen Transfer in Batch Stirred Tank Bioreactors." ChemEngineering 3, no. 1 (February 3, 2019): 14. http://dx.doi.org/10.3390/chemengineering3010014.

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In this study, microbial kinetic and oxygen transfer modelling coupled with energy analysis was applied to investigate how manipulation and control of agitator power input and air flowrate can reduce and minimise the total energy requirement in a batch aerobic bioprocess subject to constraints. The study showed that major energy savings can be made by appropriate selection of these variables and how they are controlled throughout a bioprocess. In many bioprocesses, the oxygen concentration in the liquid is controlled at a constant value. This may be achieved by maintaining the agitator power at a constant value and varying the air flowrate or vice versa, or by continuously varying both. The modelling showed that the minimum or near-minimum total energy requirement occurred when operating at the onset of impeller flooding throughout the bioprocess by continuously varying both impeller power and air flowrate over the bioprocess time. Operating at the onset of flooding may not be practical to implement in practice. However, the minimum energy can be approached by dividing the bioprocess time into a small number of time segments with appropriately chosen constant agitator powers and varying the air flowrate within each segment. This is much more practical to implement.

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28

Badarinath, Rakshith, and Vittaldas Prabhu. "Real-Time Sensing of Output Polymer Flow Temperature and Volumetric Flowrate in Fused Filament Fabrication Process." Materials 15, no. 2 (January 14, 2022): 618. http://dx.doi.org/10.3390/ma15020618.

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In this paper we addressed key challenges in engineering an instrumentation system for sensing and signal processing for real-time estimation of two main process variables in the Fused-Filament-Fabrication process: (i) temperature of the polymer melt exiting the nozzle using a thermocouple; and (ii) polymer flowrate using extrusion width measurements in real-time, in-situ, using a microscope camera. We used a design of experiments approach to develop response surface models for two materials that enable accurate estimation of the polymer exit temperature as a function of polymer flowrate and liquefier temperature with a fit of R2=99.96% and 99.39%. The live video stream of the deposition process was used to compute the flowrate based on a road geometry model. Specifically, a robust extrusion width recognizer REXR algorithm was developed to identify edges of the deposited road and for real-time computation of extrusion width, which was found to be robust to filament colors and materials. The extrusion width measurement was found to be within 0.08 mm of caliper measurements with an R2 value of 99.91% and was found to closely track the requested flowrate from the slicer. This opens new avenues for advancing the engineering science for process monitoring and control of FFF.

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29

Zhou, Hua, and Wei Song. "Theoretical flowrate characteristics of the conjugated involute internal gear pump." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 227, no. 4 (July 11, 2012): 730–43. http://dx.doi.org/10.1177/0954406212454390.

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The aim of this article is to study the theoretical flowrate characteristics of the conjugated involute internal gear pump. The conjugated involute internal gear pump has a different internal gear, the profile of which is completely conjugated to that of pinion, from the conventional involute internal gear pump. To describe briefly, the former pump is called ‘conjugated pump’ while the latter pump ‘conventional pump’. This structure makes the conjugated pump have smaller volumes of trapped fluid than the conventional pump, which indicates the conjugated pump has a better flowrate performance. Although there have been numerous investigations into gear pumps, none of them have dealt with the conjugated pumps yet. This article presents a systematic study on the theoretical flowrate characteristics of the conjugated pumps. It is expected to obtain some generalized conclusions to guide the design of internal gear pumps. Firstly, a double envelope concept is applied to derive the mathematical models of the conjugated involute internal gear couple. Next, mesh characteristics of the gear couple, which mainly decide the fluid delivery performance of the pumps, are analyzed. Finally, using a control volume approach, the theoretical flowrate characteristics of the pump under different design parameters of gears are investigated. Results show the conjugated pump has a better performance than the conventional one. To design a conjugated pump with good flowrate characteristics, it’s feasible to choose a proper shifting coefficient, a larger tooth number of the pinion, a smaller tooth number of the internal gear, a larger pressure angle and a larger fillet radius, under the condition that no tooth interference occurs.

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30

Sritram, Piyawat, and Ratchaphon Suntivarakorn. "The Efficiency Comparison of Hydro Turbines for Micro Power Plant from Free Vortex." Energies 14, no. 23 (November 29, 2021): 7961. http://dx.doi.org/10.3390/en14237961.

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In this research paper, the relationship between a crossflow turbine and propeller turbine size changes and the pond size in a free vortex power generation system was investigated. This relationship can be written in the form of a new mathematical equation using the principles of the response surface methodology (RSM) method. This study aimed to compare the efficiency of a crossflow turbine and propeller turbine to enhance a micro power plant from free vortex. The pond size in a micro power plant from free vortex was 1 m in diameter and 0.5 m in height with a 0.2 m outlet drain at the bottom. All turbines were tested at different water flowrates of 0.2, 0.3, 0.4, 0.5, and 0.6 m3/s to identify the rpm, water head, voltage, and electric current to access the waterpower, power output, and overall efficiency. At a 0.02 m3/s water flowrate, the crossflow turbine had greater overall efficiency than the propeller turbine, reaching 9.09% efficiency. From the comparison of the results of the two turbines used in the 0.5 m high cylinder-shaped generator pond, the turbine type, turbine size (height and diameter), number of blades, and water flowrate are key factors that affect the overall efficiency. The crossflow turbine can achieve greater efficiency than the propeller turbine in this generator system.

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Park, S.-H. "Development of a proportional poppet-type water hydraulic valve." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 223, no. 9 (June 2, 2009): 2099–107. http://dx.doi.org/10.1243/09544062jmes1380.

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To address the environmental problems and the safety of hydraulic systems, the development of novel water hydraulic systems using working fluids such as tap water are being developed successfully. In this study, we aim to develop a proportional water hydraulic valve using a proportional poppet as the main valve, which has an on—off function as well as a proportional function. The proposed proportional poppet-type water hydraulic valve has a simple structure with a control orifice that passes to the pilot orifice at both sides of the conventional poppet. Experiments verified that the relation between the main flowrate and pilot flowrate of the developed valve is linear and that the dynamic characteristics of the proportional poppet are satisfactory. Also, the developed valve was verified to be suitable for pulse width modulation (PWM) control and practical use for the control of water hydraulic systems.

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Amda, Julfa Muhammad, Djiwo Harsono, and Sutanto. "SIMULASI OPERASI ABWR MENGGUNAKAN SOFTWARE DCS CENTUM VP BERBASIS DATA SIMULATOR ABWR IAEA." Jurnal Forum Nuklir 13, no. 3 (January 15, 2020): 37. http://dx.doi.org/10.17146/jfn.2019.13.3.5042.

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SIMULASI OPERASI ABWR MENGGUNAKAN DCS CENTUM VP BERBASIS DATA SIMULATOR ABWR IAEA. Simulasi operasi ABWR yang dibuat adalah simulasi dari beberapa parameter pada ABWR menggunakan perangkat lunak DCS CENTUM VP. Parameter yang dikendalikan adalah Rod Position yang mempengaruhi parameter-parameter Dome Steam Temperature, Steam Flow from Core, Thermal Power, Average Fuel Temperature, Coolant Flowrate, Coolant Temperature, Coolant Quality, Turbine Governor Valve, Generator Power, Feedwater Flowrate, and Feedwater Temperature. Simulasi ini dibuat berdasarkan data yang diambil dari IAEA Simulator ABWR. Data yang dihasilkan kemudian diproses untuk mendapatkan persamaan matematisnya. Perancangan simulasi dilakukan menggunakan DCS CENTUM VP, dengan membuat tampilan simulasi pada Human Interface Station (HIS) dan program pada Field Control System (FCS).

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Dutta, Pijush, and Asok Kumar. "Modelling of Liquid Flow control system Using Optimized Genetic Algorithm." Statistics, Optimization & Information Computing 8, no. 2 (February 20, 2020): 565–82. http://dx.doi.org/10.19139/soic-2310-5070-618.

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Estimation of a highly accurate model for liquid flow process industry and control of the liquid flow rate from experimental data is an important task for engineers due to its non linear characteristics. Efficient optimization techniques are essential to accomplish this task.In most of the process control industry flowrate depends upon a multiple number of parameters like sensor output,pipe diameter, liquid conductivity ,liquid viscosity & liquid density etc.In traditional optimization technique its very time consuming for manually control the parameters to obtain the optimial flowrate from the process.Hence the alternative approach , computational optimization process is utilized by using the different computational intelligence technique.In this paper three different selection of Genetic Algorithm is proposed & tested against the present liquid flow process.The proposed algorithm is developed based on the mimic genetic evolution of species that allow the consecutive generations in population to adopt their environment.Equations for Response Surface Methodology (RSM) and Analysis of Variance (ANOVA) are being used as non-linear models and these models are optimized using the proposed different selection of Genetic optimization techniques. It can be observed that the among these three different selection of Genetic Algorithm ,Rank selected GA is better than the other two selection (Tournament & Roulette wheel) in terms of the accuracy of final solutions, success rate, convergence speed, and stability.

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34

Iswahyudi, Andi, Pratondo Busono, Yaya Suryana, Anwar Mujadin, and Dwi Astharini. "Design and Implementation of Electronic Control System of Blood Pump for Hemodialysis Machine." JURNAL Al-AZHAR INDONESIA SERI SAINS DAN TEKNOLOGI 3, no. 3 (December 20, 2017): 150. http://dx.doi.org/10.36722/sst.v3i3.221.

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Abstract – there are three methods of renal therapies, hemodialysis is the primary choise. This is because of the cheaper price compared to the CAPD. In addition, people in indonesia are still not understand the CAPD method. However, there are still many problems in the therapy using hemodialysis machine. This research aims to develop and to know the performance of the electronic control system for blood pump to match the ideal flowrate that will be used in hemodialysis treatment. This research resulting the blood pump charateristic is 179,4 step/ml when using glucose 10% and 168,2 step/ml when using glucose 20%. Based on fluid density, glucose 20% have the best performance with relative of error 0,06% at rpm 5 with 400 ml volume desired. From the result with rpm variation, the system has linearity with the slope M = 8970 step/ml = 4,2 rotation/ml using glucose 10%, and M = 8410 step/ml = 3,97 rotation/ml using glucose 20%. Which mean the slope is equivalent with the increased volume around 48,4 - 53,3 ml. It mean the blood pump rotation is constant and the system is working according the flowrate desired. It is found from the result, that many hardware factors can reducing the blood pump performance such as the roller degradation and the flexibility of the hose. Keywords – Renal Disease, Hemodialysis, CAPD, Blood pump, Flowrate

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35

Nguyen, Q. H., and S. B. Choi. "Performance evaluation of a high-speed jetting dispenser actuated by a ring-type piezostack." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 223, no. 6 (February 13, 2009): 1401–13. http://dx.doi.org/10.1243/09544062jmes1134.

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This article presents performance results of a new type of jetting dispenser driven by a ring-type piezostack actuator. The proposed dispenser can provide a very small dispensing dot size of a low viscous adhesive, from 50 to 500 cp, at a high dispensing flowrate in semiconductor packaging processes. After describing the mechanism and operational principle of the dispenser, a mathematical model of the system is derived by considering behaviours of the piezostack, the actuating spring, the dispensing needle, and the adhesive fluid dynamics. In the modelling, a lumped parameter method is applied to model the adhesive, for which the rheological property is approximately expressed by the Bingham model. The governing equation of the dispensing system is then derived by integrating the structural model with the fluid model. Based on the proposed model, the jetting dispenser is designed and manufactured. The dispensing performances such as dot size and dispensing flowrate are then evaluated from both the proposed model and experimental investigation. Subsequently, a method to control the dispensing flowrate is proposed and applied to the proposed dispenser to achieve the desired dispensing amount.

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36

Coulthard, J., B. Byrne, and Yong Yan. "Non-Restrictive Measurement of Solids Mass Flowrate in Pneumatic Conveying Systems." Measurement and Control 24, no. 4 (May 1991): 113–19. http://dx.doi.org/10.1177/002029409102400405.

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37

Park, Kiyang, Minsu Chang, and Doyoung Jeon. "Precise Flowrate Control of Fluid Gear Pumps in Automated Painting Systems Using a Repetitive Controller." Applied Sciences 9, no. 16 (August 19, 2019): 3413. http://dx.doi.org/10.3390/app9163413.

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The fluid gear pump-based system has repetitive disturbances, such as flow ripples, due to the mechanical characteristics of the gear system. The periodic disturbances have negative effects on the precise flowrate control, which is essential for consistent coating quality in the painting process. This study proposes a precise flowrate control method of the fluid gear pump-based painting system to compensate for the periodic disturbances. The compensation value of the controller output can be obtained by a repetitive controller. A compensation lookup table corresponding to the reference speed and the rotation angle can be generated through the repetitive controller. In order to secure robustness against various situations, a closed-loop system consists of the conventional proportional-derivative (PD) controller and a compensation lookup table in the form of the feedforward controller. The lookup table-based feedforward controller was compared with the open-loop controller and PD controller. Experimental results show that the proposed method is more effective than existing controllers in terms of periodic disturbance compensation. By using the results of this study, it is possible to improve the performance of the fluid gear pump-based painting system and precisely control the paint spray amount.

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38

Quintas, M. R., E. Richard, and S. Scavarda. "Implicit Non-Linear Robust Control for an Electrohydraulic System with Uncertainties." Proceedings of the Institution of Mechanical Engineers, Part I: Journal of Systems and Control Engineering 210, no. 2 (May 1996): 103–11. http://dx.doi.org/10.1243/pime_proc_1996_210_443_02.

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This paper deals with tracking the position of a linear cylinder moving a mass and controlled by a servovalve. The model of this system is non-linear with respect to state and input and has bounded uncertainties. Uncertainties are considered about the leakage flowrate of the servovalve and about the mass in movement. An implicit non-linear control with a robust term designed by the Corless-Leitmann approach is described step by step. Simulation results are shown in order to point out the advantages of this approach.

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Dahlman, P. "A comparison of temperature reduction in high-pressure jet-assisted turning using high pressure versus high flowrate." Proceedings of the Institution of Mechanical Engineers, Part B: Journal of Engineering Manufacture 216, no. 4 (April 1, 2002): 467–73. http://dx.doi.org/10.1243/0954405021520067.

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Cooling with high pressures in turning operations is an effective method for providing higher productivity. Reduced temperature and improved chip control are dependent on the pressure and flowrate of the fluid jet. The aim of the tests was to investigate how the relationship between pressure and flowrate affects the heat dissipation from the cutting zone. Tests were performed on two steel grades and one titanium alloy, allowing the same jet momentum for all materials to enable comparison between pressure and flow. Conventional cooling was used as a reference. Measurements were conducted with thermocouples attached to the clearance face of the tool. The temperature was generally reduced by approximately 50 per cent when high-pressure cooling was applied compared with conventional cooling. The results show that different pressure and flow relationships have a small but significant influence on heat dissipation from the cutting zone for the steel materials. Results show that it is important to have the right combination of pressure and flow in order to achieve optimum temperature reduction. Materials with a higher ductility benefit more from a higher flowrate while materials with a lower ductility require higher pressure. The same jet momentum was used in both cases.

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40

Sofiya, Siti, and Ya' Umar. "RANCANG BANGUN SISTEM PENGENDALIAN LAJU PRODUKSI BROWN’S GAS BERBASIS MIKROKONTROLLER ATMEGA8535." Indonesian Journal of Fundamental Sciences 4, no. 1 (May 1, 2018): 71. http://dx.doi.org/10.26858/ijfs.v4i1.6017.

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This system was developed by controlling the production flowrate of brown gas by regulating the voltage that will enter the electrolysis process, so that the flowrate of HHO gas produced in accordance with the gas rotation on the motorcycle. This research uses ATmega8535 microcontroller as a controller and potentiometer 10K which has been connected with motor rotation / speed of motorcycle that serves to move the set point that has been programmed with microcontroller. The result of this research got control response through several set point. Set point 0.2 liter / min; 0.35 liters / min; 0.45 liters / min; 0.55 liters / min; 0.7 liters / min obtained each settling time of 100s, 280s, 300s, 260s, 300s and steady state errors each set point of 5%, 2.8%, 3.3%, 2.3% 4.8%

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Liu, Shuo, Yong Cai, Kaiyou Jiang, and Daxiong Ji. "A Large-Flowrate On–Off Valve with Hollow Structure for High-Frequency Hydraulic Vibration and Impact System." Science of Advanced Materials 12, no. 9 (September 1, 2020): 1381–93. http://dx.doi.org/10.1166/sam.2020.3822.

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In high-frequency hydraulic vibration and impact systems, the high-speed reciprocating motion of the impact piston, as controlled by the main valve, transfers energy to the target. Therefore, the main valve must have a fast response speed and strong flow capacity. A novel two-stage large-flowrate on–off valve is developed in this study. The first stage is a small-flowrate servo valve, and the second stage is a large-flowrate hydraulic control valve with a hollow spool. The hollow structure not only reduces the quality of the spool and improves the valve dynamic characteristics but also improves the flow capacity and reduces the pressure drop at the valve port. A structural strength simulation is performed, and the deformation and stress of the spool are calculated. Then, the internal flow channel is extracted and the pressure drop characteristics of valve are obtained by simulation. To obtain the dynamic characteristics of the valve, the control equations of the valve are established, and the simulation model is built in Simcenter Amesim software. Then, the structural parameters of the valve body are optimized in this model. Finally, a prototype is developed for hydraulic vibration and impact systems. The experimental results show that the prototype works well, the opening time of the second-stage valve is within 6 ms, and the port pressure drop at a flow rate of 1000 L/min is only 30% of the conventional opening and closing valve of the same diameter.

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42

Gao, Haiping, Baoren Li, and Gang Yang. "Study on the influence of flow force on a large flowrate directional control valve." IFAC Proceedings Volumes 46, no. 5 (2013): 469–77. http://dx.doi.org/10.3182/20130410-3-cn-2034.00114.

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43

Oo, Sea-June, Ko-Eun Kim, Hyun-Ho Shin, and Seungbae Lee. "Precision Flow Control of Spool Valve using CFD Simulation Database in Low-Flowrate Range." Transactions of the Korean Society of Mechanical Engineers - B 43, no. 12 (December 31, 2019): 809–16. http://dx.doi.org/10.3795/ksme-b.2019.43.12.809.

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44

Kang, Ying Wei, Yang Xue, Wei Huang, and Yi Fan Li. "A Nonlinear Lumped-Parameter Dynamic Model of Power Plant Boiler Superheater." Advanced Materials Research 732-733 (August 2013): 57–62. http://dx.doi.org/10.4028/www.scientific.net/amr.732-733.57.

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Traditional models of power plant boiler superheater are incapable of simulating the operating conditions under large disturbances with high precision. To resolve this challenging problem, this paper presents a nonlinear lumped-parameter dynamic model of power plant boiler superheater. The present model describes the dynamic processes of the pressure-flowrate and the enthalpy-temperature channels with sufficient consideration of their coupling effect. To better capture the distributed-parameter property of superheater temperature, the multi-segment lumped-parameter modeling method is employed for modeling the enthalpy-temperature channel. Dynamic responses of the last-stage superheater of a 600 MW controlled circulation boiler to disturbances of the spray water flowrate, the superheater inlet enthalpy, and the absorbed heat flux are simulated. Simulation results show that dynamic responses of the present model are reasonable, and the model has high precision, which can meet the requirements for full scale simulation and control system simulation.

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Rodero, María del Rosario, Andrea Carvajal, Víctor Castro, Daniel Navia, César de Prada, Raquel Lebrero, and Raúl Muñoz. "Development of a control strategy to cope with biogas flowrate variations during photosynthetic biogas upgrading." Biomass and Bioenergy 131 (December 2019): 105414. http://dx.doi.org/10.1016/j.biombioe.2019.105414.

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46

Szabó, László, Klára Kubovicsné Stocz, Laura Szabó, Sándor Németh, and Ferenc Szeifert. "Dynamic Simulator-Based APC Design for a Naphtha Redistillation Column." Hungarian Journal of Industry and Chemistry 45, no. 1 (October 1, 2017): 17–22. http://dx.doi.org/10.1515/hjic-2017-0004.

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Abstract In this simulation study the operation of a naphtha redistillation column (a column with two feeds and three products) was analyzed with the application of Aspen HYSYS® software. The simulator, structure of local controllers and the product-quality estimators were based on the data of an industrial column in the Danube Refinery. The aim of the analysis was to identify the dynamic and steady-state effects of heating and cooling as well as the sidestream of product qualities. The relationship between the tray temperatures and the quality of the products was also identified and inferential calculations were made. Based on the identified relationships, a twolevel hierarchical control structure was developed. On the lowest level of the hierarchy are the local controllers of flowrates, liquid levels, pressure and duty. The inferential calculations are important components of the controller which serve as the controlled variables at the coordination level. The inputs of the estimators are the process data of the column, e.g. temperature, pressure and flowrate. On the top level of the control hierarchical structure the quality of the products are controlled by manipulating the setpoint of the local controllers. Based on the analysis of the Controlled Variable – Manipulated Variable relationship, closed-loop quality control was achieved with PID controllers. The result of the analysis may form the basis of Advanced Process Controller implementation.

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López, Luis Rafael, Mabel Mora, Caroline Van der Heyden, Juan Antonio Baeza, Eveline Volcke, and David Gabriel. "Model-Based Analysis of Feedback Control Strategies in Aerobic Biotrickling Filters for Biogas Desulfurization." Processes 9, no. 2 (January 22, 2021): 208. http://dx.doi.org/10.3390/pr9020208.

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Biotrickling filters are one of the most widely used biological technologies to perform biogas desulfurization. Their industrial application has been hampered due to the difficulty to achieve a robust and reliable operation of this bioreactor. Specifically, biotrickling filters process performance is affected mostly by fluctuations in the hydrogen sulfide (H2S) loading rate due to changes in the gas inlet concentration or in the volumetric gas flowrate. The process can be controlled by means of the regulation of the air flowrate (AFR) to control the oxygen (O2) gas outlet concentration ([O2]out) and the trickling liquid velocity (TLV) to control the H2S gas outlet concentration ([H2S]out). In this work, efforts were placed towards the understanding and development of control strategies in biological H2S removal in a biotrickling filter under aerobic conditions. Classical proportional and proportional-integral feedback controllers were applied in a model of an aerobic biotrickling filter for biogas desulfurization. Two different control loops were studied: (i) AFR Closed-Loop based on AFR regulation to control the [O2]out, and (ii) TLV Closed-Loop based on TLV regulation to control the [H2S]out. AFR regulation span was limited to values so that corresponds to biogas dilution factors that would give a biogas mixture with a minimum methane content in air, far from those values required to obtain an explosive mixture. A minimum TLV of 5.9 m h−1 was applied to provide the nutrients and moisture to the packed bed and a maximum TLV of 28.3 m h−1 was set to prevent biotrickling filter (BTF) flooding. Control loops were evaluated with a stepwise increase from 2000 ppmv until 6000 ppmv and with changes in the biogas flowrate using stepwise increments from 61.5 L h−1 (EBRT = 118 s) to 184.5 L h−1 (EBRT = 48.4 s). Controller parameters were determined based on time-integral criteria and simple criteria such as stability and oscillatory controller response. Before implementing the control strategies, two different mass transfer correlations were evaluated to study the effect of the manipulable variables. Open-loop behavior was also studied to determine the impact of control strategies on process performance variables such as removal efficiency, sulfate and sulfur selectivity, and oxygen consumption. AFR regulation efficiently controlled [O2]out; however, the impact on process performance parameters was not as great as when TLV was regulated to control [H2S]out. This model-based analysis provided valuable information about the controllability limits of each strategy and the impact that each strategy can have on the process performance.

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48

Niu, Hong-Hai, Yang Zhao, Shang-Shang Wei, and Yi-Guo Li. "A Variable Performance Parameters Temperature–Flowrate Scheduling Model for Integrated Energy Systems." Energies 14, no. 17 (August 30, 2021): 5400. http://dx.doi.org/10.3390/en14175400.

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Optimal scheduling strategy of integrated energy systems (IES) with combined cooling, heating and power (CCHP) has become increasingly important. In order to make the scheduling strategy fit to the practical implementation, this paper proposes a variable performance parameters temperature–flowrate scheduling model for IES with CCHP. The novel scheduling model is established by taking flowrate and temperature as decision variables directly. In addition, performance parameters are treated as variables rather than constants in the proposed model. Specifically, the efficiencies of the gas turbine and the waste heating boiler are estimated with the partial load factor, and the coefficient of performance (COP) of the electrical chillers and heat pumps are estimated with the partial load factor and outlet water temperature. Then, to deal with the model nonlinearities caused by considering the variability of COPs, the COP-expansion method is developed by adopting a specific representation of the COP and the expansion of the outlet water temperature. Finally, case studies show that the variable performance parameters’ temperature–flowrate scheduling model can account for the variation of performance parameters, especially the impacts of water temperature and the part load factor on the COP. Therefore, the proposed scheduling model can obtain more adequate and feasible operation strategy, thereby suggesting its applicability in engineering practice.

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Zhai, Y. J., and D. L. Yu. "Radial-basis-function-based feedforward—feedback control for air—fuel ratio of spark ignition engines." Proceedings of the Institution of Mechanical Engineers, Part D: Journal of Automobile Engineering 222, no. 3 (March 1, 2008): 415–28. http://dx.doi.org/10.1243/09544070jauto614.

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In this paper, a feedforward—feedback control is developed for the air—fuel ratio (AFR) of spark ignition engines using neural network estimators. To maintain the AFR at stoichiometric value, the throttle angle change is seen as a disturbance, from which the air flowrate is predicted. The injected fuel is also predicted using the inverse of the fuel injection dynamics. The proposed method is evaluated on an engine simulation benchmark and the performance is shown much improved over proportional—integral control. The new method needs moderate computation and therefore has strong potential to be used in production engines.

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50

Idris, R., N. Harun, and Mohamad Rizza Othman. "A port-stream based equation oriented modelling of complex distillation column: A dividing wall column case study." Applied Chemical Engineering 3, no. 2 (December 9, 2020): 68. http://dx.doi.org/10.24294/ace.v3i2.588.

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Dividing wall column (DWC) offers higher degree of freedom in comparison with the conventional column. Furthermore, the different sections configurations within the column are highly interacting with several recycle loops. Facing with such complex unit operation, describing its behaviour encourages the focal point on the resolution of ideal modelling approaches. Equation oriented (EO) modelling of DWC has been studied by several researchers involving complex algorithm and methodology. In this work, a new approach for modelling of DWC is presented. The modelling methodology involves variables connectivity based on ports and streams that is admissible to equation-oriented flow sheet. To verify the functionality of the proposed method, the modelled DWC is validated with two case studies depicted from experimental literature data to separate alcohol mixture and fatty acid fractionation. The model development was performed in MOSAIC, a web-based modelling tool and run in gPROMS. The model shows good convergence and has less than 10% error when compared to the above mentioned case studies. To furthermore extend the model capability, relative gain array (RGA) analysis was conducted for the fatty acid fractionation to determine the best control configuration in DWC. Result shows that L-S-V and L-S-B configurations are the best control configurations. Our analysis also shows that reflux flowrate, side flowrate and vapor boilup are best to control distillate product, side product and bottom product, respectively.

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