Effect Of Tank Size Research Articles

Optimal Design of Water Tank Size for Power System Flexibility and Water Quality

The increasing penetration of renewable energy, such as wind power, has brought great challenges to the power system operation due to its uncertainty. Flexibility, which measures the ability of power system to deal with the uncertainties, is critical for power system to adapt to the new era of renewable energy. The rising electrical demand of the water distribution system (WDS) creates opportunities for power system to leverage the flexibility provided by WDS. This paper investigates the water-energy relationship between these two systems and makes full use of the water pumps and tanks in the WDS to enhance the power system flexibility. Current WDS designs did not consider well the role WDS plays in the power system. This hinders the WDS from being fully used by power system to provide flexibility. An optimization model is proposed to determine the optimal tank size of WDS, which may provide the maximum available flexibility of power system. The effect of tank size on water quality is also investigated to ensure that the supplied water quality is not compromised. Moreover, a Benders-based heuristic algorithm is proposed to find the optimization solution more efficiently and to protect the data of each energy system. Results of case study highlight the merit of the proposed optimization design and the advantage of using WDS to provide flexibility for power system.

Nonlinear behavior of ground-supported circular reinforced concrete tanks

This study aims to investigate the effect of various parameters on the seismic behavior of concrete tanks. A finite element method using pushover and time-history analysis is developed to investigate the seismic behavior of circular ground-supported tanks. The response modification factor (R) is evaluated based on nonlinear static and time-history analyses. R-factor is one of the key parameters in seismic design. In liquid containing structures, R-factor in current codes and standards are based on empirical values. Therefore, a justifiable guideline to accurately determine these values is yet to be developed. This study shows that the effect of tank size, material non-linearity, base condition, and earthquake frequency is significant. Also, fixed based and shallow tanks have higher R values compared to hinged based and tall tanks, respectively. Based on the results of this study, it is found that the value of R specified in current practice is not appropriate.

Effect of Tank Size on Zebrafish Behavior and Physiology.

Simple SummaryLiving space is an important aspect of animal welfare. Understanding the effects of welfare on experimental animals would help in drawing a precise conclusion. In this work, zebrafish in different tank sizes were studied through behavioral and physiology tests. Results showed that changes in the tank size affected zebrafish behavior; those that lived in small tanks behaved less boldly, had poor stamina, and spent much time on movement. Therefore, researchers should focus on zebrafish’s living space to generate valid data from laboratory studies.Environmental conditions strongly affect experimental animals. As a model organism, zebrafish has become important in life science studies. However, the potential effect of living environment on their behavior and physiology is often overlooked. This work aimed to determine whether tank size affects zebrafish behavior and physiology. Tests on shelter leaving, shelter seeking, shoaling, stamina, and pepsin and cortisol levels were conducted. Results showed that zebrafish behavior is easily affected by changes on the tank size. Fish that lived in small tanks behaved less boldly, had poor stamina, and spent much time on movement. Sex differences in behavior were only evident in the shelter seeking tests. Tank size had no effect on pepsin and cortisol, but cortisol concentrations in males were lower than those in females. This study suggests that zebrafish behavior is easily influenced by their living environment, and future related studies should consider their living space.

Transient Cooling of Waxy Crude Oil in a Floating Roof Tank

The transient cooling of waxy crude oil stored in a floating roof tank located in alpine region is studied by means of numerical simulation, accomplished with a two-dimensional model in cylindrical coordinates with the finite volumes method. The typical evolution of transient natural convection and temperature distribution is investigated which can be divided into four stages. For the transient natural convection, it is concluded as the formation, expansion, degradation, and vanishing stage, along with it is the evolution of temperature field regarded as the local cooling, integral cooling, the thermal stratification, and heat conduction course. Special attention is given to the solidified process of waxy oil and its influence on the cooling process of crude oil. Moreover, the effect of tank size, the temperature gradient between oil and ambient, viscosity, and Cp of waxy crude oil on the cooling rate is investigated. The main characteristic of cooling process obtained from numerical results shows a good agreement with the temperature test results from a large floating tank in the oil depot.

Effect of tank size on kLa and mixing time in aerated stirred reactors with non‐newtonian fluids

AbstractThe most important scale‐up parameters of aerated bioreactors are investigated in 42 and 340 L vessels, with water and various xanthan gum and carboxymethyl cellulose solutions. The study focuses mainly on mass transfer (kLa) measurements under various operating conditions. The relevance of existing correlations is discussed. The traditional viscosity‐contribution approach appears unable to predict the changes in kLa during scale‐up and an alternative formulation is proposed. The effect of rheology on power consumption and mixing time is in fair agreement with works published on this topic.

Generalized SDOF system for dynamic analysis of concrete rectangular liquid storage tanks: effect of tank parameters on response

This paper presents the results of parametric studies on the seismic response of concrete rectangular liquid storage tanks using the generalized single-degree-of-freedom (SDOF) system. The effects of height of liquid and width of tank on the dynamic response of liquid storage tanks are investigated. The liquid level varies from the empty condition to a full tank. Also, instead of the commonly used ratio of width of tank to liquid height, Lx/HL, the ratio of width of tank to full height of the tank wall, Lx/Hw, is used as a characteristic parameter of tanks to study the effect of tank size on the dynamic response. The trends of added mass of liquid, effective height, and natural frequencies for different sizes of tanks are established. The values of the added mass of liquid due to impulsive hydrodynamic pressure and the effective height in the relationship with the ratios Lx/Hw and HL/Hw are determined and can be used in the seismic design of liquid storage tanks. Since the natural frequencies of liquid-containing structures are within a band of frequencies between that of a full tank and that of an empty tank, the recommended frequency to be used in the design of the tank wall is the frequency that causes the maximum dynamic response .

Effect of Tank Size and Geometry on the Flow Induced by Circular Bubble Plumes and Water Jets

Ambient flow field and circulation patterns induced by circular bubble plumes and water jets in tanks of different sizes were studied in rectangular and square water tanks. A nonstationary nature of the flow was observed in all experiments and its dominant oscillation frequency was found to directly relate to the tank size. The flow circulation patterns were similar for bubble plumes and water jets, but changed significantly with tank size and geometry. Strong three-dimensional effects were observed in a rectangular tank, resulting in flow entraining in the longer plane and flow detraining in the shorter plane, especially for the bubble plume tests. A relationship was developed to relate the tank size to the patterns of circulation cells. Nearly isotropic turbulent flow conditions were obtained in all experiments, but the effect of tank size and geometry on the magnitude of the turbulent stresses was more pronounced in the bubble plume tests.

Study on energy dissipation pattern in vibrating fluid filled cylindrical shells with a constrained viscoelastic layer

The modal strain energy method is used to study the energy dissipation pattern in vibrating cylindrical shells with a viscoelastic damping layer, for various circumferential and axial modes. The effect of tank size, boundary condition and height of contained fluid on the distribution pattern is also investigated. The regions of energy dissipation concentration are identified. The effect of redistribution of the (initially uniformly distributed) constrained viscoelastic material by concentrating it in the above regions is studied.

The Influence of Tank Size and Impeller Geometry on Turbulent Flocculation: I. Experimental

ABSTRACT The effects of tank size and impeller geometry on the particle size distribution after 30 min of flocculation at constant characteristic average velocity gradient, Gm, were studied. Flocculation was performed in three square tanks 5-, 28-, and 560-L volume with Rushton turbines and A310 fluid foil impellers. The floc size was recorded in situ using a photographic technique, and the resulting photographs were analyzed with an image analysis system. The results show that the cumulative particle size distribution shifts to a smaller particle size range with increasing tank size, regardless of impeller type. A similar shift in the cumulative particle size distribution was observed when the impeller type was switched from the A310 fluid foil to the Rushton turbine, regardless of tank size. The volume mean floc size, floc standard deviation, and maximum stable floc size were found to be controlled by the turbulence intensity in the impeller discharge zone and not by Gm. Key words: Tank size; impeller g...

Turbulence in flocculators: Effects of tank size and impeller type

AbstractPast research shows that for the same power per unit volume, flocculation performance varies with tank size and impeller type. This study was performed to characterize effects of scale and impeller design on turbulence produced in the flocculation process. The study was performed with a Rushton turbine and an A310 foil impeller in three square tanks of 5‐, 28‐ and 560‐L volume. Fluid velocities were measured using a dual‐channel laser Doppler velocimeter with an enhanced burst spectrum analyzer. Flocculation tanks were operated at a constant average unit‐mass energy‐dissipation rate of 0.0016 m2/s3. The results show that the turbulence intensity and local turbulent energy‐dissipation rate were higher for the Rushton turbine than for the A310 impeller. The turbulence intensity was found to increase with increasing tank size regardless of impeller type. The local turbulent energy dissipation rate decreased for the Rushton turbine and remained constant for the A310 impeller with increasing tank size.

Full Scale Measurements on LPG Carrier of Semi-Membrane Tank Type under Servise Condition

In this paper a summary of results is presented of full scale measurements on a LPG carrier of semi-membrane tank type which have been carried out for about two years during her voyage between Japan and the Persian Gulf.The unmanned measurements have been made on dynamic loads caused by liquid sloshing in a LPG tank of a restricted cargo filling ratio of either over 90% or below 30%. The test includes also measurements of reaction forces acting on a tank dome supporting the tank at upper deck structure. Long term measurements of ship notion as well as stresses due to longitudinal bending of hull girder have also been carried out. A statistical study has been made on a relationship between the ship motion and the frequency of occurrence of the liquid sloshing in LPG tank.The results of the measurements have been compared with results of bench test on liquid sloshing in model tank in order to investigate into the effect of tank size on the magnitude of impact load due to sloshing.