Tank Level Research Articles

A Heuristic Method for Modeling Odor Emissions from Open Roof Rectangular Tanks

This paper presents heuristic equations for estimating odor emissions from open-roof rectangular tanks as a function of the tank orientation, wind direction, wind speed and distance of the emitting surface from the tank top. These types of equations are important because they may help to improve emission calculations to avoid overestimations, which are damaging to the plant owner, and underestimations, which are negative for the population around the plant. Odor emissions were determined for four tanks with the same area, different shape factors and two different orientations and then used as inputs for a dispersion model in order to calculate separation distances and evaluate their differences. The results show that different separation distances were obtained depending on the tank orientation, shape factor and level of filling. Future field applications to verify and improve the proposed equations are desirable. If the effect of the tank orientation on odor emission is proven, the design of future industrial plants containing open-roof rectangular tanks should consider the results of detailed wind data analysis.

Novel Strategy of Adaptive Predictive Control Based on a MIMO-ARX Model

Many industrial processes include MIMO (multiple-input, multiple-output) systems that are difficult to control by standard commercial controllers. This paper describes a MIMO case of a class of SISO-APC (single-input, single-output adaptive predictive controller) based upon an ARX (autoregressive with exogenous variable) model. This class of SISO-APC based on ARX models has been successfully and extensively used in many industrial applications. This approach aims to minimize the barriers between the theory of predictive adaptive control and its application in the industrial environment. The proposed MIMO-APC (MIMO adaptive predictive controller) performance is validated with two simulated processes: a quadrotor drone and the quadruple tank process. In the first experiment the proposed MIMO APC shows ISE-IAE-ITAE performance indices improvements of up to 25%, 25.4% and 38.9%, respectively. For the quadruple tank process the water levels in the lower tanks follow closely the set points, with the exception of a 13% overshoot in tank 1 for the minimum phase behavior response. The controller responses show significant performance improvements when compared with previously published MIMO control strategies.

Rollover stability analysis of liquid tank truck taking into account the road profiles

The rollover stability of the tank truck was quite poor compare with others due to the influence of the oscillating liquid inside the tank. In addition, it was also affected by road excitation during driving. Therefore, the paper presents the impact of the road profiles in turning and lane change maneuvers on the rollover stability characteristics of a liquid tank truck. Firstly, the study applies the quasi-static method and the roll model to built the dynamic model of a circular cross-section tank truck. After that, the Lagrange method and the D'Alembert's principle are used to set up the differential equations which are then used to investigate rollover stability of vehicle corresponding with each liquid level. The research used the value of the load transfer ratio (LTR), crest factor of LTR and the roll angle of suspension to evaluate vehicle stability in the time domain and the transfer function magnitude of LTR in the frequency domain. The simulation results had shown that the tank truck tends to a rollover phenomenon at the fluid level in tank of 50% and 75% (0.8m and 1.2m) when the vehicle ran survey road profiles in a steady state turning maneuver and in a lane change maneuver as there was not the road excitation. The research results can provide recommendations when operating liquid tank truck, developing control systems and warning of rollover.

Predicting daily water tank level fluctuations by using ARIMA model. A case study

The intrinsic dynamical features of water demand highlight the need of proper operational management of tanks in water distribution networks. In addition, due to the water resource scarcity, sustainable management of urban systems is essential. For this purpose, the aid of a predictive model is crucial since it allows to give short term forecasts that can be used to predict the oscillations of relevant parameters, i.e. tanks level and/or water demand. Urban water managers can use these predictions to implement actions aimed at the optimisation of the network function. Among several modelling techniques, the univariate time series analysis is instrumental since it allows forecasting the studied parameter by using the measurements of the parameter itself. In this paper, an autoregressive integrated moving average (ARIMA) model is calibrated on water levels data, measured in an urban tank in Benevento, Campania region (Italy) and then tested on a large dataset not used to tune the parameters. The validation and forecast phases show good performances of the model on a short-term forecast horizon demonstrating the excellent potentiality of this techniques. Finally, the residuals and errors analysis complete the work suggesting possible future implementations and improvements of this technique.

Tank Volume Calculations and Level Calibrations for Partially-Filled Liquid Process and Storage Vessels

Tank Volume Calculations and Level Calibrations for Partially-Filled Liquid Process and Storage Vessels

PID control implementation in multiple input and multiple output (MIMO) water mixing tank via Ziegler–Nichols and direct synthesis methods

This study deals with the modeling of two PI controllers to control first-order systems [cold water (CW) to tanklevel and hot water (HW) to temperature] using Ziegler–Nichols (ZN) and direct synthesis methods and to test bothcontrollers for set-point tracking and disturbance rejection modes for multiple input and multiple output (MIMO)water mixing tank. The ZN method is a technique used for tuning controllers, and it used both proportional andintegral actions in the present investigation. This method was performed by setting the integral (I) and derivative(D) gains to zero. It was applied to the open-loop reaction of the process to the change in the water level and thetemperature (the control variables) and the plotter on the computer recorded the response. The evaluated processvariables, such as K (for the proportional action) and ? (for the integral action), are plugged into the ZN equationwith the specific multiplier constants for the gains of a controller with PI actions. The ZN technique was utilized toobtain a PI controller for both the CW to tank level system and the HW to temperature system. The direct synthesis(DS) method was applied to a desired closed-loop transfer function. The design of the controller was based on aprocess model. This method was applied to set-point changes in the control system and later fixed to responsesto disturbances. The DS technique was implemented on the two systems, the CW to tank level and the HW totemperature. It was able to control the impact of the sensitive HW to temperature system. However, the controllerperformance across the CW to tank level system was extremely inefficient as oscillations were observed.

PID Control Implementation in Multiple Input and Multiple Output (MIMO) Water Mixing Tank via Ziegler-Nichols and Direct Synthesis Methods

This study deals with the modeling of two PI controllers to control first-order systems (cold water [CW] to tank level and hot water [HW] to temperature) using Ziegler-Nichols (ZN) and direct synthesis methods and to test both controllers for set-point tracking and disturbance rejection modes for Multiple Input and Multiple Output (MIMO) water mixing tank. The ZN method is a technique used for tuning controllers, and it used both proportional and integral actions in the present investigation. This method was performed by setting the integral (I) and derivative (D) gains to zero. It was applied to the open-loop reaction of the process to the change in the water level and the temperature (the control variables) and the plotter on the computer recorded the response. The evaluated process variables, such as K (for the proportional action) and ? (for the integral action), are plugged into the ZN equation with the specific multiplier constants for the gains of a controller with PI actions. The ZN technique was utilized to obtain a PI controller for both the CW to tank level system and the HW to temperature system. The direct synthesis (DS) method was applied to a desired closed-loop transfer function. The design of the controller was based on a process model. This method was applied to set-point changes in the control system and later fixed to responses to disturbances. The DS technique was implemented on the two systems, the CW to tank level and the HW to temperature. It was able to control the impact of the sensitive HW to temperature system. However, the controller performance across the CW to tank level system was extremely inefficient as oscillations were observed.

Real-time consumer aware and alert system based on smart water tank

As population is growing water scarcity is becoming a raising issue year after year. The reasons may vary but there are two main factors which could be considered as key reasons of water shortages. Fresh water sources in Saudi Arabia are very limited and water desalination plants can't cover the high demand. omeowners should pay higher attention to their faucet’s leakages, not only to reduce water wastage but leakages could also impact their own water expenses in addition to our environment and economy. This project presents two tiers (homeowner / national water company) water shortage solution, we can't control the sources in our technical field, but we can improve water distribution system and develop a water monitoring system for clients. Our prototype consists of two parts. A web site to display statistical information and illustrations of different types of estimates and calculations, for national water employees to make water distribution decision more efficient besides clients to monitor their consumption rate and notice alerts of any leakages. The second part of our project focuses on hardware which well be sensing the water level and consumption then send the readings to the server to be presented on the website. It has an ultrasonic sensor installed in water container to detect water level, also there are three faucets each one is connected to a flow meter sensor to detect amount of dispensed water. All sensors are connected to a microcontroller where we embedded functions contains algorithms to calculate consumption rate, leaks detection and tank level to be sent through the Ethernet shield to the website. Finally, our monitoring approach is inexpensive and will reduce shortages by guiding the water pumping only to most needed districts; also, it will take care of water wastage issue approximately around 40% water can be stored using this developed technology.

RANCANG BANGUN WATER LEVEL CONTROL BERBASIS SONOFF SMART SWITCH

The prototype of an automatic water tank filling system based on a sonoff smart switch that works based on the volume of water level in a tank based on a sonoff smart switch has been successfully created. This study aims to determine the working principle of the sonoff switch and automatic water tank filling system. The water sensor used in this study is a float switch type that works based on changes in the value of the high volume of the tank water. For automatic filling of the water tank, a sonoff smart switch and also a float switch have been used as a switch to drain and disconnect the electric current to the pump. The design results show that this automatic water tank filling system can work well, where if the water tank level is below 20% then the water pump will turn "ON" and if the water level in the tank is above 90% then the water pump will turn "OFF".

Reliability analysis of complex water distribution systems: the role of the network connectivity and tanks

Abstract A reliable water distribution network (WDN) can provide an adequate supply service to customers under both normal and abnormal working conditions. The WDN reliability analysis, therefore, is a keystone to improve the supply service efficiency. Strategies for reliability analysis are usually proved on small WDNs, which do not compare with large real complex systems in terms of number of water tanks, pressure reduction valves, variable speed pumps, controlled devices and possible alternative water supply schemes. The topological changes due to pipeline interruptions impact on emptying–filling of water tanks and network pressure status. This work proposes a two-level procedure for mechanical reliability assessment, suited for large real WDNs. It leverages a path/connectivity-based approach to set up reliability indicators for global-level analysis and local screening of the most critical scenarios. The employed advanced hydraulic model includes the automatic detection of topological changes and the robust modelling of water level in tanks using the generalized global gradient algorithm. The extended period simulation enables the reliability assessment of alternative water supply schemes and the sensitivity of tanks and controlled devices to single failure events. The procedure is demonstrated on a real complex network, being consistent with the ongoing digital transition in the WDN management sector.

Echo state networks for online, multi-step MPC relevant identification

This paper presents an online nonlinear system identification algorithm for model predictive control relevant identification, based on an echo state network (ESN) trained using the recursive least squares method with a directional forgetting factor. The proposed online ESN architecture is formed by a reservoir, with fixed recurrent connections, and a reservoir readout mechanism, which is updated online to define the network output. The ESN is used to perform a multi-step prediction task, which can be used for model-predictive control purposes. The proposed online identification algorithm is evaluated in simulation using a conical tank level process and compared with the results of other approaches from the literature. The results show that the proposed algorithm is able to identify the nonlinear characteristics of the process without considering any prior information about it. In addition, the results for long-range predictions are better than the ones obtained with a model linear in its parameters and several baseline ESN models from literature, after the adaptation phase of the proposed algorithm.

Design procedures for a passive pyramid solar still with an automatic feed water system

Design procedures are presented here using conceptual design to optimize the performance of a passive pyramid solar still by introducing an automatic feed water system to compensate for the evaporated water from the tank. The procedures may be adopted for passive or active solar still systems. The water level is optimized to be fixed as it shall reduce due to continuous evaporation if no automatic method is used. That will improve the performance of the solar still and increase its output yield. The design procedures considered customer needs which are surveyed and products specifications are decided. Design targets are specified using the quality function deployment. Three design alternatives are proposed and compared, and the best alternative is chosen based on the decision matrix. An auxiliary tank was added between the storage tank and the solar still with a ball valve to maintain a constant water level inside the auxiliary tank and a screw jack to control the elevation of the auxiliary tank and water level. Based on the hydrostatic principle, the elevation of the water level inside the auxiliary tank and solar still must be the same. Therefore, controlling the elevation of the water level inside the auxiliary tank using the screw jack controls the water depth inside the solar still. The proposed feedwater system can maintain the water level inside the solar still to its optimum value that improves the solar still productivity and convenience for the end-user.

Gain-Scheduled Level Controller for FESTO MPS PA Station Tank

In this article, a Gain Scheduling (GS) approach is proposed to control the FESTO MPS PA Station Tank level by controlling the centrifugal pump. The open loop transfer function for each operating condition is experimentally obtained. The data from the open-loop system is imported to MATLAB in order to get the transfer function for each condition. The data shows that each operating point has a different transfer function in terms of gain and time constant. Based on this, a gain-scheduling controller is proposed to handle the variations of process model parameters. The proposed controller parameters are adapted based on the operating conditions of the system. These parameters include the tank capacitance and the flow pipe resistance and/or the valve resistance to the flow. Two different controller techniques for FESTO MPS PA Station Tank level control are applied, verified and compared. The first controller is based on classical Proportional Integral (PI) controller, while the second one is based on the proposed gain scheduling controller. Experimental results show that the proposed gain-scheduling controller can manipulate the process at different operating conditions with parameters variations in order to give uniform performance. The classical PI controller has failed to achieve this requirement at different operation conditions.

Evaluation of modified biofloc system with filtration unit in controlling suspended solids and inorganic nitrogen concentrations in a recirculating aquaculture system

AbstractBACKGROUNDBiofloc technology systems (BFT) often encounter difficulties in controlling suspended solid levels in tanks. The oxygen consumption rates and ammonia removal rates of bioflocs as the BFT system shifts from assimilation towards nitrification have rarely been reported. Thus, the performance of the BFT system with a filtration unit was evaluated.RESULTSPreliminary work found that the optimal screen pore size and recirculating flow rate were 100 μm and 3000 L day−1, respectively. The BFT system with the filtration unit could maintain suspended solids in the fish tank below 50 mg‐SS L−1 while retaining significantly higher suspended solids in the biofloc reactor (509 ± 44.6 mg‐SS L−1). The daily starch addition at a C:N mass ratio of 10:1 in phase I (day 1–38) induced the biofloc formation that kept TAN and nitrite levels below 1.0 mg‐N L−1. The fraction of inorganic nitrogen compounds increased from 2.5% in phase I to 27.6% in phase III (day 56–70). TAN removal rates increased from 3.0 mg‐N g‐SS−1 day−1 during phase I to 10.34 ± 0.392 mg‐N g‐SS−1 day−1 after complete nitrification occurred. Relatively constant oxygen consumption rates of the bioflocs (149.1 ± 9.53 mg‐ O2 g‐SS−1 day−1) were observed for the entire experiment.CONCLUSIONThe BFT system with a filtration unit was effective in controlling suspended solid and inorganic nitrogen concentrations. Nitrogen treatment pathway of BFT system was assimilation during startup period but gradually shifted to nitrification. Oxygen consumption rates of the bioflocs are relatively constant regardless of the pathways responsible for nitrogen treatment. © 2021 Society of Chemical Industry (SCI).

Quantitative failure analysis for static electricity-related explosion and fire accidents on tanker vessels under fuzzy bow-tie CREAM approach

Cargo operations on tanker vessels involve high risks to crew and the marine environment. At the time of loading and unloading of cargoes and tank cleaning operations, consequences of accidents may be severe such as loss of lives, property loss and marine pollution. One of the most critical accidents is an explosion which may advance to a large fire. An explosion may occur due to flammable and combustible materials, electric arcs, dangerous operations, like hot work on deck, or static electricity. This study focuses on the issue of static electricity, which is one of the serious threats onboard and can cause large explosions under hazardous conditions if a discharge is in contact with nearby flammable gases or air mixture. In a bow-tie structure, static electricity-related explosion and fire accident was determined as the top event. In the fault tree diagram, intermediate events were considered as the flammable atmosphere in a tank, operational failures, technical failures, and unsafe practices which cover direct human errors. Fuzzy logic and Cognitive Reliability and Error Analysis Method (CREAM) were used for quantitative failure analysis, and the probability of accident risk was found as 6.31E-02. Findings show that the most critical contributions to the top event are minimal cut sets of lack of monitoring cargo tank atmosphere, inadequate actions for reducing the O2 level in tank, failure to understand safety data sheets, failure to follow procedures, non-bonded ullage & sample apparatus. The research provides a significant contribution to the literature and gives information regarding static electricity risks to ship officers, tanker safety superintendents and other maritime authorities to improve the safety of cargo operations.

The Application of Geophysical Methods in Identification of Subsurface Fractures in The Vicinity of a Poor Performance Percolation Tank

Percolation tanks are constructed to conserve the rainwater in large quantities and allow more infiltration in its area of influence. Sometimes due to heavy fracture concentration/thick weathered zone, the water in percolation tank migrates fast in short period and tank becomes dry, which leads to early scarcity conditions. The village karkatta of taluka and district Latur is one such village, where water is provided by constructing two wells in the vicinity of percolation tank. The water level in the percolation tank depletes fast and the tank becomes dry in early summer. Also one cement nala bandhara was constructed in the downstream of the nala. The village is funded by UNICEF to implement MUS (Multiple Water Users) project. The area is surveyed by applying both electrical resistivity methods and low frequency electromagnetic methods in submergence of tank as well as in the downstream of percolation tank. The studies reveal that the leakages are due to thick vesicular basalt followed by fractured massive basalt. Suitable remedial measures are recommended to slow down the subsurface flow so as to improve the performance of the percolation tank.

ABOUT STABILITY OF THE MOVEMENT OF THE REFUELING VEHICLE EQUIPED WITH DIGITAL SYSTEM OF BRAKE FORCES DISTRIBUTION DURING THE EMERGENCY BRAKING

The impact of enforced oscillations of the free surface of fuel in the car tank on the stability area of a closed digital brake force distribution system is considered. The object of the study is the process of stabilized movement of the tanker during the emergency braking. The subject of the study is a large tanker with a gross weight (3-3.5) *104 kg, equipped with a tank with a volume of (17-20) m3 and a system of direction stability. The goal of the work is investigation of the impact of transported fuel fluctuations on the stability of the refueling vehicle during the emergency braking and introducing of methods for selecting values of variable parameters of the electronic brake force distribution system to minimize it. Conclusion. Considering the oscillations of the free surface of the liquid in the mathematical model of disturbed movement of a closed system of stability significantly reduces the stability area of the system in the low frequency range due to the loop, the size and position of which depend on the filling level of the tank. Need to choose an envelope loop that according to different levels of tank filling.

Particle swarm algorithm and OLE for process control based PID design for dual capacity water tank

Typical dual capacity tank level control systems suffer from long control regulation times, large nonlinear output deviations and hysteresis. Facing with this situation, an optimization of multi-parameter control of PID controller using particle swarm algorithm (PSO) is proposed to reduce the overshoot phenomenon. By analyzing the mathematical model of the dual capacity water tank, the PSO intelligent algorithm is combined with the PID controller to obtain the optimal control parameters and performance indicators in MATLAB, through the OPC communication protocol, the water level of the tank is transmitted to the Kingview monitoring system to display the change curve in real time. The results showed that the PSO algorithm and OPC protocol can combine the complex algorithm function of MATLAB with the excellent plotting of Kingview, play a key role in the dual capacity tank level systems.

Physical Modelling of Flow and Head along with Dead-end and Looped Manifolds

In this study, physical models were designed and fabricated to investigate the hydraulic behaviour of dead-end and looped PVC manifolds. The physical models consisted of a water supply tank with overflow, PVC manifolds, steel supports, collection tank, pump, pressure sensors and valves to allow flow control. Throughout the study, the water level in the supply tank was kept constant. The hydraulic behaviour of dead-end manifolds was investigated using different spacing, S between outlets (S= 3m, S=2.5m, S=2m, S=1.5m, and S=0.75m). The hydraulic behaviour of looped manifolds was investigated using a single outlet spacing of 1.5m. The comparison between the hydraulic behaviour of looped and dead-end manifolds was carried out using the data of the 1.5m outlet spacing. The value of uniformity, U for dead-end and looped manifolds was 82% and 92%, respectively. The value of friction ratio, fn/f1, was found to be 33 and 0.18 for dead-end and looped manifolds, respectively. The experimental data of this study were used to validate selected formulae for estimation of the friction correction factor (G Factor). The results showed that the equation proposed by Alazba et al. (2012) yielded the most satisfactory estimation. The performance of the selected formulae was tested using two statistical indices.

Farm Silage Facilities and Their Management for the Prevention of Anaerobic Bacteria Spore Contamination in Raw Milk

At feed-out, aerobic spoilage of silage enables an increase in anaerobic spore-forming bacteria (ANSB) that may enter the total mixed ration (TMR). The aim of our study was to understand whether in hot summers the silage structures and management may affect the level of ANSB in milk for long-ripening cheese production. A survey of silage facilities, management, and their relationships with silage, TMR, feces, and milk ANSB most probable number (MPN) content was conducted in the Po Valley during summer months. Silo type did not affect the mean ANSB, but only the wideness of their value distributions, with a narrow range for bags and a wider range for bunkers. The unloading equipment affected the ANSB count; the front-end loader with cutter was associated with a lower ANSB count—probably as a result of the reduced surface left after daily silage removal. Silo length and daily removed face width were the main factors affecting contamination of silage by spore-forming bacteria during summer, with longer silos and wider surface removal reducing ANSB contamination—probably as a consequence of reduced aerobic spoilage at the silage surface. The silage contamination by spore-forming bacteria within a log10 2 MPN g−1 allowed a low concentration of spore-forming bacteria at the farm bulk milk tank level. Fecal ANSB levels did not factor into the regression that explains the ANSB in farm milk. It has been found that silage facilities’ features and their management are an important first step to reduce the extent of ANSB contamination at the farm level.