Tank Liquid Level Research Articles

Hardware implementation of a novel intelligent fuzzy fractional order proportional-integral (FFOPI) controller for a coupled tank liquid level control system

Hardware implementation of a novel intelligent fuzzy fractional order proportional-integral (FFOPI) controller for a coupled tank liquid level control system

Numerical investigation on the thermal performance of a molten salt tank under different electric heating method

Two-tank molten salt (MS) thermal energy storage (TES) technology is an efficient and widely used energy storage technology. This study develops a two-dimensional discrete model (2DIM) using the Modelica language to accurately and quickly represent molten salt temperature distribution and heat loss, applicable to system-level analysis in thermal power systems. It also uncovers variations in heat loss, cooling rate, and required auxiliary electric heating power across different tank volumes, liquid levels, and MS temperatures, offering guidance for optimizing design, energy management, and operational strategies. Additionally, the study examined the impact of different electric heater placements on the performance of the thermal storage system. The results show that heating the gas inside the tank is more effective than traditional direct electric heating, reducing molten salt heat loss by 25.89 % and increasing energy storage efficiency by 0.17 %.The research provide a reference for the study of efficient utilization of TES tank in different thermal systems.

Numerical design of a flow restrictor for tanked liquid nitrogen undergoing reduced-gravity flights

NASA and the United States are designing multiple reduced-gravity cryogenic payloads to study various two-phase flow phenomena that will be ground-tested and subsequently flight-tested onboard parabolic flights. The setup will undergo 25+ parabolas per flight, during which liquid nitrogen will be cyclically or continuously demanded from a supply Dewar. The minimum gravity level during a parabolic maneuver is 0 ± 0.05 g, which can last around 20 seconds, and the maximum expected gravity is 2 g, which lasts for 40-50 seconds. This Computational Fluid Dynamics (CFD) study focuses on the design and optimization of a bi-directional perforated plate and a ring baffle to help ensure single-phase liquid nitrogen outflow during all flight phases, regardless of supply tank liquid level or gravity level. CFD analyses carried out using ANSYS FLUENT indicate that a double perforated plate with an open area percent equal or less than 0.63% can achieve high values of expulsion efficiency. Structural analyses performed using the ANSYS Static Structural solver determined the minimum plate thickness needed to withstand gravitational and hydrodynamic forces experienced during the flight.

IoT Enhanced Smart Aeroponics System

Abstract: Recently, urban farming has gained popularity as people become more aware of the quality of their food. Aeroponics is an urban farming technique that uses air as its growing medium. Compared to traditional farming and hydroponics, aeroponics offers a significant reduction in water usage while increasing yield. This study introduces an aeroponics system integrated with Internet of Things (IoT) technology for real-time and automated monitoring. The system maintains the pH level of the nutrient solution using a pH sensor and monitors temperature and humidity with an A DHT sensor. A peristaltic pump, coupled with a ultrasonic sensor, regulates the tank's liquid level. All these processes are accurately timed and shared on the ThingSpeak Platform and Blynk App for user interaction, facilitated by the ESP 32 Micro controller

Controlling a Single Tank Liquid Level System with Classical Control Methods and Reinforcement Learning Methods

In this study, the control of the single tank liquid level system used in control systems has been carried out. The control of the single tank liquid level system has been performed with the classic PI, modified PI, state feedback with integrator action, and Q learning algorithm and SARSA algorithms, one of the artificial intelligence methods. The tank system to be modelled was carried out using classical physics, namely Newton's laws. Then, the mathematical model obtained of the system that are continuous model in time is acquired. The originality of the study; the non-linear liquid tank system is controlled by classical controllers and reinforcement methods. For this purpose, the system was firstly designed to model the system, then the system has been linearized at a specific point in order to design classic PI, modified PI, and state feedback with integral. After that, agents of the Q Learning algorithm and SARSA algorithms were trained for the system. Then the agents have controlled the single-level tank system. The results of the classic controllers and supervised controllers are contrasted with regard to performance criteria such as rising time, settling time, overshoot and integral square error. Consequently, Q learning method has produced 0.0804-sec rising time, 0.943 sec settling time and 0.574 integral square errors. So, Q learning algorithm has produced and exhibited more thriving and successful results for controlling single liquid tank system than PI, Modified PI, state feedback controllers and SARSA.

Fuzzy PID Controller Design for a Coupled Tank Liquid Level Control System

In industrial processes, the most important loop is the liquid-level control loop. The coupled tank system CT-100 becomes an essential apparatus for process control researchers. This paper introduces two controller techniques to control the water level in the second tank as a single input single output system. The PID controller is designed to control the linearized model, where the controller parameters are tuned using the Ziegler- Nichols tuning method. In addition, Fuzzy PID is designed based on adequate knowledge and experience. The proposed control approaches are simulated using MATLAB Simulink. Then, the obtained results using these controllers are compared in terms of time response specifications and the ITAE criterion. It is also, tested for step-change tracking signal and disturbance rejection. Finally, the simulation results showed that the Fuzzy PID controller has a robust performance.

Design of Double Tank Liquid Level Control System Based on Fuzzy PID

Liquid level is one of the main parameters in industrial production process control. There are many problems such as interference and delay in the dual capacity water tank. It is usually difficult to meet the strict production requirements with the conventional PID control scheme. The corresponding transfer function is firstly deduced through the material balance equation in this article. By testing, the performance of conventional PID needs to be further improved. Then build the fuzzy PID model in Matlab/simulink and carry out simulation verification. By comparing with the PID simulation effect, the results show that under fuzzy PID control, the overshoot of the system is effectively reduced and the adaptability is strong. It reflects that the control strategy has a good reference value.

Optimizing Three-Tank Liquid Level Control: Insights from Prairie Dog Optimization

The management of chemical process liquid levels poses a significant challenge in industrial process control, affecting the efficiency and stability of various sectors such as food processing, nuclear power generation, and pharmaceutical industries. While Proportional-Integral-Derivative (PID) control is a widely-used technique for maintaining liquid levels in tanks, its efficacy in optimizing complex and nonlinear systems has limitations. To overcome this, researchers are exploring the potential of metaheuristic algorithms, which offer robust optimization capabilities. This study introduces a novel approach to liquid level control using the Prairie Dog Optimization (PDO) algorithm, a metaheuristic algorithm inspired by prairie dog behavior. The primary objective is to design and implement a PID-controlled three-tank liquid level system that leverages PDO to regulate liquid levels effectively, ensuring enhanced stability and performance. The performance of the proposed system is evaluated using the ZLG criterion, a time domain metric-based objective function that quantifies the system's efficiency in maintaining desired liquid levels. Several analysis techniques are employed to understand the behavior of the system. Convergence curve analysis assesses the PDO-controlled system's convergence characteristics, providing insights into its efficiency and stability. Statistical analysis determines the algorithm's reliability and robustness across multiple runs. Stability analysis from both time and frequency response perspectives further validates the system's performance. A comprehensive comparison study with state-of-the-art metaheuristic algorithms, including AOA-HHO, CMA-ES, PSO, and ALC-PSODE, is conducted to benchmark the performance of PDO. The results highlight PDO's superior convergence, stability, and optimization capabilities, establishing its efficacy in real-world industrial applications. The research findings underscore the potential of PDO in PID control applications for three-tank liquid level systems. By outperforming benchmark algorithms, PDO demonstrates its value in industrial control scenarios, contributing to the advancement of metaheuristic-based control techniques and process optimization. This study opens avenues for engineers and practitioners to harness advanced control solutions, thereby enhancing industrial processes and automation.

A non-reference detection method of the external ultrasonic liquid level switch using the PZT

Oil tank level is an important control parameter in oil depot management. According to the principle that the liquid in the oil tank can absorb the guided wave propagation energy in the tank wall, this paper studied a non-reference detection method of external ultrasonic liquid level switch based on the signal energy change value between the current and the previously liquid level detection signal. The experimental results show that the ultrasonic guided wave with the center frequency of 30 kHz is sensitive and low misjudgment to liquid level detection. According to the experimental setup, the liquid level judgment threshold is set to 0.9890. The influence of the liquid on the guided wave propagation in the tank wall decreases with the frequency of the guided wave increase. Finally, the effectiveness of the proposed method is verified on a diesel oil tank. The research of this paper provides a method for the research of oil tank external liquid level switch technology, and provides an idea for the research of oil tank liquid level measurement based on ultrasonic guided wave.

Analysis of the effects of recycling on process control

Abstract The union of different devices in order to obtain a specific response for a process is commonly called a control system. For a control system, it is necessary to have one or more controllers. Among the most used in the industrial sector are the PID and PI controllers. Next to these controllers is the control software. Scilab is a good example of control software. It is characterized as free code software, with no cost for its acquisition, in addition to having a large computational power and integrated tools, such as Xcos, intended for modeling and simulation. For the union with Scilab, there is Arduino. Such a mixture can be used, for example, to control liquid levels in tanks. In this context, the present work aims to study the tank-level control system based on PID and PI controllers through the union between Scilab and Arduino. Phenomenological models were developed based on closed-loop control (feedback control system) of the process with two tanks not coupled with recycle. Furthermore, for comparison purposes, two approaches were used for each process: one considering the saturation of the manipulated variable and the other without the presence of such saturation. At first, there was a need to implement an anti-windup system. For tuning the controller parameters, the ISE method was used, executed through a programming code developed in Scilab. The parameters found for the two systems were tested on a made-up experimental bench. Therefore, using the block diagrams and the method here called “ISE method”, satisfactory values were obtained for the control parameters. These were ratified in the tests carried out in the experimental module. Level control was achieved with greater prominence for the PI controller since there is one less parameter to be tuned and processed by the system. This controller provided results close to the PID controller for cycles up to 50%. In general, the PI controller showed maximum response deviations smaller than the PID, such as deviations of 1.55 cm and 2.40 cm, respectively, for the case with 75% recycle. It was also clear the influence of the saturation of the manipulated variable on the system response, but not on the tuning of the controller parameters.

Nonlinear Tank-Level Control Using Dahlin Algorithm Design and PID Control

Liquid-level control in tanks is widely used in various industrial sectors. Due to problems arising from the case that the liquid level is above or below the recommended, the process of its control is of great significance. The proportional integral differential (PID) controller is one of the most widely used controllers in applications that require accuracy and optimal automatic control. In this paper, single and coupled ship fuel tank systems are discussed. In addition, mathematical models and their linearization using two different approaches are presented. The two control approaches are used to maintain the specified liquid level in tanks. The first is based on the design of standard PID controllers, with the application of the Ziegler–Nichols, Takahashi tuning, and Auto-tuning methods. The second approach, proposed by the authors, is based on the application of the Dahlin algorithm. The simple modification of the Dahlin controller, which can avoid the “ringing” of the control signal, is suggested in the paper. Moreover, the lower limit of the decrease in the desired time constant, which ensures the desired behavior of the system, is determined. The comparisons provided for different performance indexes show the advantages of the modified Dahlin algorithm approach compared to the standard PID controllers. Furthermore, the comparison with the literature-known approaches is realized.

Optimization of Condensate Transfer Pump in the Hydrocarbon Condensate Stabilization Unit of Natural Gas Liquefaction Plant – An Industrial Case

PT. Badak NGL is a commercial LNG producer located in Bontang, Indonesia. In recent years, the decline in LNG production of PT. Badak NGL results in a lower hydrocarbon condensate flow rate. To prevent power losses since its pump operated at below rating, a new operation scheme was proposed. This new scheme adjusts the way of pump is operated without any alteration in terms of pump characteristics. Three pumps operated intermittently for 8 hours per day at a maximum flow rate. The pump power consumption was calculated based on electric current data monitored relay panel. The results show that the pump energy saved by 60% with the absolute value of annual energy efficiency of 957.7 MWh. This study contributes to reducing the greenhouse effect by 412 tons eq CO and the annual production cost of around USD 130,000. The new scheme reliability examines by evaluating pump vibration, pump performance, hydrocarbon condensate quality, and condensate tank liquid level. The result shows that the pump’s vibration in the range of 0.21 in/sec with a steady winding temperature.

Liquid level control in two tanks spherical interacting system with fractional order proportional integral derivative controller using hybrid technique: A hybrid technique

This paper proposes a Liquid Level Control in two tanks spherical interacting system (TTSIS) with Fractional Order Proportional Integral Derivative (FOPID) controller using hybrid system. The proposed approach is the consolidation of chaotic Henry gas solubility optimization (CHGSO) and Feedback Artificial tree (FAT), and later it is known as CHGSO-FAT technique. The FOPID controller is modeled as Fractional Order System for a spherical tank's liquid level control. The Spherical tank system is important in nonlinear operation, because its variation on the radius of tank and the interaction of the two tanks with FOPID sliding surface. Moreover, FOPID controller is proposed the system output is directly used to tune the system parameters. The proposed controller is enhanced by increasing the fractional values of the derivative term FOPID sliding surface. The performance indices, as settling time, rise time, peak overshoot and peak time is analyzed. The proposed system is performed on MATLAB/Simulink working platform. The mean, median and standard deviation for 100 iterations with proposed system is 0.338, 0.4173 and 0.00334.

RETRACTED: Cuckoo Search Optimization based PI Controller Tuning for Hopper Tank System

The paper work focuses on soft computing and Conventional controller tuning approach to design of PI controller, for a nonlinear hopper tank liquid level control system process Industries. The automation industries provide conventional techniques where it is impossible to maintain its settling time which motivates to do the research in this field. The system processes the combination of a conical and cylindrical tank for providing Multi-region based mathematical modelling to obtain the first order with delay time (FOPDT) process transfer function model. The Ziegler Nichols, Cohen-coon, Tyreus Luben, CHR (Chien, Hrones, and Reswick), IMC (Internal Model Control), Direct Synthesis, FOPI(Fractional Order PI) Conventional tuning formulae and Cuckoo Search Optimization (CSO) algorithm are used to optimize the servo regulatory responses of PI controller. The integral and proportional gain of the PI controller is said to produce the fastest settling time and reduces the error using performance indices and achieves Liquid Level control in hopper tank. Comparison is made for the various conventional controller tuning methods with Cuckoo Search Optimization tuning responses and identified to CSO-PI method offers enhanced Optimized Performance of settling time which was about 105.58 s which is relatively less while comparing to Conventional PI controller tuning methods for a different region based system.

Implementation of PID controller for liquid level system using mGWO and integration of IoT application

Industrial automation is a multi-disciplinary study field that is constantly evolving. This research proposes IoT-based real-time liquid level monitoring and control in a single tank system. A PID controller with parameters sets using a novel modified Grey Wolf Optimization (mGWO) algorithm is used to manage the liquid level. The PID controller was then built on the ESP32 microcontroller module, and an android-based application was created utilizing the Blynk platform for IoT plant monitoring and control. The mGWO algorithm is used in MATLAB to optimize the Kp, Ki, and Kd values of PID controller parameters. The Arduino IDE is used to create the microcontroller programing as well as the interface for the Android application to the ESP32 microcontroller module. The results reveal that a single tank liquid level control system based on mGWO outperforms Ziegler–Nichols and SIMC tuning approaches. Furthermore, the adoption of an IoT application-based user interface boosts the plant’s control and monitoring flexibility.

Surrogate-Assisted Multi-Objective Optimization of a Liquid Oxygen Vacuum Subcooling System Based on Ejector and Liquid Ring Pump

As an important combustion aid for aerospace vehicles, subcooled liquid oxygen of high density can be used to increase loading capacity of a spacecraft. Providing a large amount of cryogenic propellant in a short time with a strict energy consumption limitation is a challenge in the design of the fuel filling system. The authors proposed a vacuumed subcooling system combined with an ejector and liquid ring pump to vacuum a liquid oxygen tank and obtain subcooled liquid oxygen. After the liquid oxygen tank is vacuumed to an intermediate pressure by the ejector, it is further vacuumed to 10 kPa using the liquid ring pump. The infinitesimal method was used to simulate the thermodynamic processes involved. Taking the ejector working fluid mass flow rate, jet pressure, intermediate pressure, initial tank liquid level, and liquid ring pump speed as optimizing variables, optimization was conducted to determine the optimal vacuuming time, remaining liquid level in the tank, pumping speed difference, and nitrogen consumption. The sample set was generated by the optimal Latin sampling algorithm. The surrogate assisted Non-dominated Sorting Genetic Algorithm (NSGA-III) multi-objective algorithm was used to construct a system optimization framework. The non-dominated solutions were added to the sample set to improve the generalization ability of the Gaussian Process Regression (GPR) in the Pareto front. A convergent Pareto solution set was obtained after multiple iterations. The influence of different optimization variables on each optimization objective was analyzed using the Pearson correlation coefficient method. The optimization results show that the trade-off scheme can obtain the subcooled liquid oxygen at 10 kPa and 73 K with a remaining liquid level of 74.84% in a total vacuum time of 19.93 h. The efficiency of the liquid oxygen vacuum subcooling system can be improved significantly.

Fuzzy Sugeno with Gain Compensator Based on Pole Placement for Controlling Coupled Water Tank System

The control of liquid level in tanks is a classic problem in process industries. Most of the liquid will be processed by chemical or mixing treatment in the tanks. Because of that, the liquid level in the tanks must be regulated, so that in order for this system to work as we want, it needs a control strategy. Therefore, this research will use a control strategy using fuzzy sugeno with a gain compensator based on pole placement for controlling level of tank 2 in the coupled water tank system with setpoint is 10 centimeters at time 0 seconds and 8 centimeters given at time 1000 seconds. Wherein, the gain compensator based on pole placement is used to make the output system robust to changes in setpoint with zero steady-state error and fuzzy sugeno for faster time response. The results show that using the fuzzy sugeno with a gain compensator based on pole placement can follow setpoint given with 0 centimeters of steady-state error, 0% for overshoot, 44,6538 seconds for rising time, 62,2688 seconds for settling time and can follow setpoint changes in 58,8662 seconds.

Anomaly Detection and Analysis Based on Deep Autoencoder for the Storage Tank Liquid Level of Oil Depot

In the industrial control system of oil depot, the change of storage tank liquid level is closely related to the transportation process and site management of oil depot. It is of great significance to detect the abnormality of storage tank liquid level data for the safe and stable production of oil depot. A data-driven anomaly detection strategy is proposed by analyzing the non-periodic time series data of the oil storage tank liquid level. Based on the convolutional autoencoder algorithm to learn the features and patterns of a large number of samples, the strategy is carried out by reconstructing the samples and calculating the reconstruction error, which not only does not rely on the labeled samples, but also improves the detection precision. This paper chooses three algorithms of convolutional autoencoder, RNN (Recurrent Neural Network) autoencoder and LSTM (Long Short-Term memory) autoencoder for experimental analysis. Experiments were carried out on the oil tank historical data set and NAB (Numenta Anomaly Benchmark) simulation data set respectively. The results show that the accuracy of convolutional autoencoder is 98% and the F1 score is 82%, which is more practical for the scenes with real-time requirements.

An intelligent self-tuning fuzzy-PID controller to coupled tank liquid level system

An intelligent self-tuning fuzzy-PID controller to coupled tank liquid level system

Experimental investigation on the thermo-hydraulic characteristics and occurrence boundary of geyser in a cryogenic pipe

• The essential characters are summarized for the effective recognition of geyser in cryogenic engineering. • The tank pressure and liquid level have an effective suppression effect on geyser. • The occurrence and transition boundary of geyser is divided by a new dimensionless parameter Ae . • The geyser might occur when Ae is larger than 2, and a strong geyser might occur when Ae is larger than 4. In the present study the thermo-hydraulic characteristics of geyser in the cryogenic fuel transportation pipe of a liquid rocket is experimentally investigated using liquid nitrogen. The typical thermo-hydraulic appearances are characterized and analyzed in the geyser process to effectively recognize the occurrence of geyser in practical engineering. The effect of interfering factors such as heat flux, liquid level and tank ullage pressure on geyser are explored. Moreover, based on the new proposed dimensionless parameter of the maximum energy storage ability ( Ae ), the occurrence boundary of geyser is divided. It could be concluded from the results that a clear periodic pressure and temperature change accompanied by periodic plenty vapor ventilation could serve as an indication for geyser’s occurrence, and the eruption of cryogenic geyser has a similar appearance as that in the geothermal field. It is found that a higher tank ullage pressure and liquid level could reduce the geyser’s intensity, and a violent boiling will occur instead of geyser when the heat flux is extremely high. It is a feasible way to eliminate geyser in the cryogenic pipe by increasing the pressure inside the pipe via increasing the tank ullage pressure or liquid level in the tank. Moreover, it is found that a weak geyser would occur in LN 2 and LO 2 when Ae exceeds 2, and then as Ae being larger than 4, a strong geyser might occur with a noticeable pressure peak.