Tank Model Research Articles

UAV-Mounted Tank for Processing Agricultural Land with Liquid Agrochemicals

To process agricultural crops, unmanned aerial vehicles carrying tanks with liquid chemicals are used. The paper highlights that containers made of polypropylene and polyethylene exhibit inferior qualities compared to those made of fiberglass, specifically, in terms of strength, thermal stability, resistance to ultraviolet rays, and service life. (Research purpose) To design and manufacture a tank made of composite fiberglass material with a water hammer damper. (Materials and methods) S-glass and epoxy vinyl ester resin were selected for the tank, as they exhibit superior resistance to chemical influences. To construct the tank elements, spray application, impregnation of glass fiber filler in a closed form, and winding were used. (Results and discussion) A comparative analysis was conducted on tank models, assessing their performance with and without a water hammer damper. The effectiveness of the suggested solution has been substantiated through the utilization of KOMPAS-3D software in the KompasFlow application, Within this software, the hydraulic shock is simulated to propagate inside the tank, reflecting off the walls, and gradually diminishing. Load and strength calculations for the fiberglass tank were performed by considering fiberglass parameters using the APM FEM application. (Conclusions) A tank model designed for application of liquid chemical substances in crop spraying from unmanned aerial vehicles has been developed. Innovative methods were employed in the manufacturing of the tank components. Additionally, careful consideration was given to the feasibility of maintenance and reparability. The tank’s volume (experimental sample) measures 0.0158 cubic meters, with a length of 480 millimeters, a width of 216 millimeters, a thickness of 3.6 millimeters, and a weight of approximately 4 kilograms. The design for mounting the composite tank on the unmanned aerial vehicle ensures that the weight of the unmanned aerial vehicle does not impact the tank.

Numerical Computation of Restoring Time and Prediction of Self-Righting Process

Excellent self-righting performance is important to guarantee the normal navigation of Unmanned Surface Vehicles (USVs) after overturning, and the restoring time is an important index in design requirements. Traditionally, the static stability method and experiments on full-scale vehicles were used to analyze the large-angle stability of the USV. However, when it comes to the analysis of self-righting performance, the traditional static stability method will cause improper integration, and experiments are not convenient. To solve these problems, an improved static stability method was proposed, and a whole self-righting process simulation of a physical model was finished. The numerical simulation method was used to predict the self-righting process of a USV under four working conditions. Firstly, a midpoint average method based on the static stability theory was adopted to compute the static restoring time, and the results were compared with the results of the references, which verifies the effectiveness of the midpoint average method. Also, the midpoint average method is convenient because it only needs the restoring arm curve, the width and the gravity center height. Then, a numerical simulation of a physical model in static water was finished, and an experiment for a physical model in a towing tank was conducted. Comparing the restoring time of the midpoint average method, the numerical simulation and the experiment, the results show that the numerical simulation has high accuracy. Moreover, the numerical simulation was used to predict the self-righting process and analyze the self-righting performance of a USV under four working conditions.

Effects of innovative reinforced concrete slit shaft configuration on seismic performance of elevated water tanks.

Elevated water tanks are considered crucial infrastructure due to their significant role in supporting essential services. A strong ground motion may result in a failure or significant damage to a reinforced concrete shaft of an elevated water tank because hysteric energy dissipation is limited to the formation of plastic hinges at the base of the shaft, while the nonlinear properties of the rest of the shaft remain underutilised. The innovative system of assembling RC shafts for elevated water tanks using a slit wall technique was developed to enhance energy dissipation along with the shaft height by introducing slit zones. The comparative nonlinear dynamic analysis between three-dimensional models of elevated water tanks with different shaft diameters and heights was conducted using SAP2000 software. The results of elevated water tanks with slit and solid reinforced concrete shafts were compared. The research findings showed that during a seismic event, the slit zones increased the ductility of the shaft, reduced stress concentration in the lower part of the shaft, and provided uniform stress distribution throughout the shaft's height. The effect of the innovative system is especially noticeable in the elevated water tanks with tall and slender shafts.

Structural analysis and optimal design of a spherical thin-walled stainless steel water tank without reinforced tie ribs

A spherical thin-walled stainless steel water tank without reinforced tie ribs has been designed to address the issues of easy fracture and corrosion of the ribs, difficulty in maintenance and cleaning, and short service life exposed during the use of thin-walled stainless steel water tanks with reinforced tie ribs. Firstly, an analytical model of a flat steel thin-walled water tank without reinforced tie ribs was established and subjected to static analysis under water pressure. The deformation and stress distribution patterns of the side molded plate of the flat box were obtained. Secondly, a spherical non ribbed thin-walled stainless steel water tank structure was designed with circular cross-section under different box bulge parameters, and its mechanical response characteristics under water pressure load were analyzed. A strengthening scheme was designed for the bottom box molded plate. Once again, optimize the combination design of the box scheme and the reinforcement scheme, and analyze their static, thermodynamic, and thermal solid coupling performance. Finally, the Latin Hypercube Sampling method was used to generate experimental design samples, and a response surface approximation model of a spherical thin-walled stainless steel water tank without reinforced tie ribs was constructed. The wall thickness of the box molded plate, skeleton, and reinforcement were used as design variables, and the maximum deformation and maximum equivalent stress were used as constraints. The lightweight design was carried out with the goal of minimizing mass. The research results indicate that the design program and parameter selection method for spherical thin-walled stainless steel water tanks without reinforced tie ribs proposed in the article are efficient and feasible, and can provide technical reference and theoretical support for the layout and overall optimization design of non ribbed thin-walled stainless steel water tank structures.

Generalized thermodynamic modeling of hydrogen storage tanks for truck application

Hydrogen-driven heavy-duty trucks are a promising technology for reducing CO2 emissions in the transportation sector. Thus, storing hydrogen efficiently onboard is vital. The three available or currently developed physical hydrogen storage technologies (compressed gaseous, subcooled liquid, and cryo-compressed hydrogen) are promising solutions. For a profound thermodynamic comparison of these storage systems, a universally applicable model is required. Thus, this article introduces a generalized thermodynamic model and conducts thermodynamic comparisons in terms of typical drive cycle scenarios. Therefore, a model introduced by Hamacher et al. [1] for cryo-compressed hydrogen tanks is generalized by means of an explicit model formulation using the property cv2P from REFPROP [2], which is understood as a generic specific isochoric two-phase heat capacity. Due to an implemented decision logic, minor changes to the equation system are automatically made whenever the operation mode or phase of the tank changes. The resulting model can simulate all three storage tank systems in all operating scenarios and conditions in the single- and two-phase region. Additionally, the explicit model formulation provides deeper insights into the thermodynamic processes in the tank. The model is applied to the three physical hydrogen storage technologies to compare drive cycles, heat requirement, dormancy behavior, and optimal usable density. The highest driving ranges were achieved with cryo-compressed hydrogen, however, it also comes with higher heating requirements compared to subcooled liquid hydrogen.

Automation of superconducting cavity cooldown process using two-layer surrogate model and model predictive control method

Superconducting cavity is the key equipment of the superconducting accelerator, which provides higher acceleration voltage and higher frequency power per unit length, and saves equipment space. Superconducting cavities need to be gradually cooled from ambient temperature (300 K) to the superconducting temperature (4.2 K or below) during the test and operation. The temperature difference on the cavity must be strictly limited during the cooldown process to prevent excessive thermal stress on the surface of the superconducting cavity. Since this cooldown process for the superconducting cavity is a typical large hysteresis, non-linear process that is difficult to control automatically using decoupled proportion integral derivative (PID) methods directly, a less efficient manual control scheme is normally adopted. In this paper, 3D numerical simulation, 1D pipe and 0D tank model with artificial neural network (ANN) were combined to generate a two-layer surrogate model that can balance computational accuracy and speed, to improve the automation and cooling efficiency of the superconducting cavity cooldown process. In order to achieve automatic control of the cooling procedure for the superconducting cavity, a model predictive control (MPC) approach was also built on the basis of this two-layer surrogate model. According to the results of the experiment test, the improved method could realize a quick and smooth cooldown process of the superconducting cavity, during which the temperature difference on the cavity could satisfy the requirements. Additionally, the improved automatic cooldown method was more adaptable and saved 29 % more time than the original manual control method. The foundation for a more intelligent automated control of future large cryogenic systems or other system with the large hysteresis, non-linear properties, was laid.

Structural sizing of a hydrogen tank for a commercial aircraft

To respond to the current climate crisis, hydrogen-powered aircraft are seen as a promising solution in the aviation sector to cut down CO 2 emissions. Hydrogen-fueled aircraft present however huge challenges, especially due to the complex storage of hydrogen. To achieve a reasonable fuel energy density for medium- to long-range missions, hydrogen must indeed be stored in liquid form in big and heavy pressurized tanks. Tank design must so be included in conceptual design, which now has an important impact on the aircraft. This study proposes a structural sizing methodology for a liquid hydrogen tank for a commercial aircraft. A parametric model of a cylindrical cryogenic tank placed at the back of the cabin in a conventional aircraft is created and sized to withstand pressure, bending, torsion and shear loads. The process integrates sizing standards for pressurized structures of the current CS-25 regulation in its methodology and remains general enough to consider both integral and non-integral tanks of any dimensions or materials. Initial analyses show a clear dependency of the tank’s performance as well as the optimal stiffening structure configuration on the design pressure.

Slope Stability Analysis of Mounded Storage Tank under Different Compaction Coefficients

Mounded storage tank is to cover the storage tank with compacted soil on the ground to avoid steam cloud explosion, ensuring the stability and safety of the storage tank. In view of the influence of large diameter and surface radian of the tank, slope stability of mounded storage tank under different compaction coefficients has become the focus of research. In this paper, a series of laboratory tests were carried out to obtain the physical and mechanical parameters of the soil samples collected from the overburden of one specific engineering project. On this basis, Plaxis2D finite element software was used to establish a numerical model of the horizontal tank with a diameter of 7.6 m and a length of 76 m and the mounded slope with a height of 16.25 m as the research object. The effects of different compaction coefficients, slope angles, and overburden thicknesses on the slope stability of the mounded storage tank are investigated. Results indicate that the slope stability coefficients increase with the increase of compaction coefficient but decrease with the increase of slope angle and overburden thickness. Under the condition of the compaction coefficient 0.75–0.95, slope angle 30°–60°, and overburden thickness 0.5–1.3 m, the sensitivity ranking on the slope stability of mounded storage tank is: compaction coefficient, slope angle, and overburden thickness. The analysis results can provide an important theoretical basis and technical support for the safety and stability evaluation of mounded horizontal tank project.

A Second-Order Generalized Total Variation with Improved Alternating Direction Method of Multipliers Algorithm for Electrical Impedance Tomography Reconstruction

The issue of Electrical Impedance Tomography (EIT) is a well-known inverse problem that presents challenging characteristics. In order to address the difficulties associated with ill-conditioned inverses, regularization methods are typically employed. One commonly used approach is total variation (TV) regularization, which has shown effectiveness in EIT. In order to meet the requirements of real-time tracking, it is essential to acquire fast and reliable algorithms for image reconstruction. Therefore, we present a modified second-order generalized regularization algorithm that enables more-accurate reconstruction of organ boundaries and internal structures, to reduce EIT artifacts, and to overcome the inability of the conventional Tikhonov regularization method in solving the step effect of the medium boundary. The proposed algorithm uses the improved alternating direction method of multipliers (ADMM) to tackle this optimization issue and adopts the second-order generalized total variation (SOGTV) function with strong boundary-preserving features as the regularization generalization function. The experiments are based on simulation data and the physical model of the circular water tank that we developed. The results showed that SOGTV regularization can improve image realism compared with some classic regularization.

Comparison of Empty and Oil-Filled Transformer Tank Mode Shapes Using Experimental and FEM Modal Analysis

In this paper, the mode shapes of an empty and oil-filled transformer experimental model tank are obtained using 3D finite element method (FEM) modal analysis. For verification of the FEM analysis results, experimental modal analysis (EMA) is carried out in both cases using appropriate impact hammers and accelerometers. Simulated and measured results are visualized and compared for mode shapes in a frequency range of interest for both empty and oil-filled tanks. In order to avoid overly stiff FEM models of transformer tanks, the welded joint modeling technique is presented and analyzed in detail. For an oil-filled tank, the most accurate results are calculated in the model where the welded joint is modeled as half the tank wall’s thickness. In that case, the mean absolute error for the given ten-mode shapes is 1.7 Hz. Also, mesh sensitivity analysis is performed. It is concluded that a 10 mm maximum element size is an optimal solid (3D) mesh. However, shell mesh can be used to reduce computing requirements.

Investigating Pressure Patterns in Transformer Tanks after an Interturn Short Circuit: A Finite Element Approach

When an inter-turn short-circuit fault occurs during the operation of a transformer, the arc generates energy that causes the temperature in the tank to rise. This in turn increases the temperature of the insulating oil, vaporizing it, and the rising pressure in the tank acts on the tank such that it can easily explode. The arc energy is related to the initial pressure of the gas and its production in the tank. The pressure wave propagates in insulating oil, and the transient pressure at any point in the path of the pressure wave is the superposition of vectors of forward- and backward-traveling waves. The authors of this study applied a finite element simulation software to establish a model of the transformer tank and used it to analyze the changes in pressure in the tank and on the wall as well as the factors influencing this phenomenon. The results show that the wall pressure of the transformer increases with time after the failure of the interturn short circuit. The pressure wave travels from the initial position of the arc to the periphery and decreases with diffusion effects. The influence of pressure on the transformer tank can be reduced by selecting an appropriate location for the pressure-release valve and can in turn prevent the tank from rupturing due to the impact of rising pressure.

Study on the shape and motion of bubbles in the tank model with a central column aboard the Chinese Space Station

It is of great significance for fluid management under microgravity to explore the morphological characteristics of annular bubbles in a tank with a central column. The propellant residue can be evaluated by measuring the annular bubble's volume, and the estimation of the mass center of tanks also needs to know the liquid distribution. An experiment cabin is designed and the experiments of filling and emptying the tank model are carried out aboard the Chinese Space Station. Two kinds of annular bubbles surrounding the central column under microgravity are observed experimentally for the first time, which appear during the processes of filling and emptying the tank model, respectively. Furthermore, the profiles of these annular bubbles are obtained by theoretical derivation. Numerical procedures based on the theoretical expressions are developed and the bubble profiles can be predicted in few seconds. The evolutions of the movement and shape of small bubbles are also explored experimentally and numerically. Under the constraint of minimum free surface energy, several small spherical bubbles will merge into a bigger spherical bubble, which are driven by small disturbances and their initial velocities, and the bigger bubble will locate in the middle region of the tank model at equilibrium. When the volume of the bubble keeps increasing, the surface of the bubble will become the specific Delaunay interface, whose the mean curvature is constant, under the constraints of the propellant management device and the tank wall.

The Effect of Monetary Policy on Consumption Inequality: An Analysis of Transmission Channels through TANK Models

The Effect of Monetary Policy on Consumption Inequality: An Analysis of Transmission Channels through TANK Models

Heterogeneity and Aggregate Fluctuations: Insights from Tank Models

Heterogeneity and Aggregate Fluctuations: Insights from Tank Models

A Two-Dimensional State-Space Model for Metal Hydride Storage Tanks and Parameter Sensitivity Analysis

Modeling of metal hydride storage tanks remains a challenging issue. In most of the literature, the charge and discharge of metal hydride storage tanks are controlled by the hydrogen flow rate. However, the case of controlling the charge and discharge of metal hydride tanks by pipe pressure has rarely been reported in the literature. Aiming at this problem, this work presents a two-dimensional state-space model that takes the pipe pressure as the system input and assumes that the tank temperature can be measured. Then, the First-order Trajectory Sensitivity Analysis method is used to analyze the parameter sensitivity of several selected unknown parameters. The results of the sensitivity analysis indicate that six parameters: entropy change for desorption ∆Sd, enthalpy change for desorption ∆Hd, activation energy for absorption Ea, activation energy for desorption Ed, plateau flatness coefficient φ and plateau hysteresis coefficient β have higher sensitivity to the model state.

Deformation model for hollow cylindrical-shaped variable volume tank

Deformation model for hollow cylindrical-shaped variable volume tank

Determination of the stress-strain state of models of steel cylindrical tanks using the “ANSYS” program

In the world, metal cylindrical shell constructions occupy a leading position in the construction of reservoirs for various purposes, bodies of water pressure generating towers, television towers, chimneys, lighting masts, tower cranes and similar engineering structures. In this direction, in developed countries such as the USA, Germany, Japan, and Russia, special attention is paid to increasing the load-carrying capacity of cylindrical shell structures, ensuring earthquake resistance and priority, reducing metal consumption, preventing the resulting deformations, and thereby ensuring their reliable operation. In this regard, one of the important tasks is to increase the priority of various construction structures, optimize their shape and size, improve existing calculation methods, and develop modern advanced methods of construction preparation and assembly.

TWO-DIMENSIONAL CFD ANALYSIS OF A HOT WATER STORAGETANK WITH IMMERSED OBSTACLES

A comprehensive study was conducted to develop a two-dimensional mathematical model for a thermal storage tank containing internal disk-shaped obstacles. This model, incorporating appropriate initial and boundary conditions, was solved using the built-in solvers of the licensed COMSOL Multiphysics 5.6 software. The COMSOL model demonstrated a maximum deviation of 2.2% from experimental results and even smaller discrepancies compared to ANSYS Fluent, validating its accuracy in describing the charging and discharging processes of a sensible heat storage tank with internal obstacles. Using this validated algorithm, numerical studies were performed to analyse temperature distribution and performance indicators for three distinct tank configurations. Among these configurations, the storage tank with a middle disk consistently exhibited superior performance. This tank achieved the highest mixing efficiency, as evidenced by smoother variations in the Richardson number and a more uniform temperature distribution. It also attained the highest capacity ratio (90.12%) and exergy efficiency (81.67%), indicating its effectiveness in heat retention and the quality of stored thermal energy. Furthermore, it demonstrated the highest charging efficiency at 67.51%, highlighting its ability to store incoming heat more effectively. These findings establish the tank with a middle disk as the most efficient configuration for thermal energy storage and uniform temperature distribution.

Numerical analysis of influencing factors on wave load for an amphibious aircraft

Numerical method of wave load for an amphibious aircraft is carried out in this paper, and its effectiveness is verified by comparing with towing tank model test. It shows that at the same wavelength and speed, the aircraft’s wave load is positively correlated with the change of wave height, but with the increase of wavelength, the difference shows a gradually decrease. And wave load is positively correlated with the speed, the greater the speed, the greater the wave load is. The wave load decreases with the increase of the wavelength. The peak load generally occurs in the short wave state of 1.2 times the length of the fuselage. With the increase of the wavelength, the aircraft load gradually decreases.

Predicting Flood Water Level Using Combined Hybrid Model of Rainfall-Runoff and AI-Based Models

Vietnam faces on significant human and property losses from floods almost every year. Therefore, the aim of this study is to provide timely and highly accurate flood prediction information using a developed hybrid model by combination of the rainfall-runoff model and AI-based model. We used Tank model as a rainfall-runoff model for peak flood discharge and parameter calibration was conducted by GA (genetic algorithm) and PS (pattern search). The sum of squared residuals (SSR) and weighted sum of squared residuals (WSSR) as objective functions were used for peak flood discharge evaluation. The simulated flood discharge was converted as flood water level by rating curve and Monte Carlo simulation was applied to estimate the confidence bounds for 95% confidence level. These estimates were then utilized as input data for the AI-based models to identify the strengths and weaknesses of each model and develop an optimal flood water level prediction model. Two AI-based models, deep neural network (DNN) and long short-term memory (LSTM), were used for flood water level prediction. The LSTM model demonstrated the best performance with a correlation coefficient (CC) of 0.98, normalized root mean square error (NRMSE) of 0.04, and Nash-Sutcliffe efficiency (NSE) of 0.98.