Short Tanks Research Articles

An efficient new assay for measuring zebrafish anxiety: Tall tanks that better characterize between-individual differences

BackgroundZebrafish (Danio rerio) are increasingly being used to model anxiety. A common behavioral assay employed for assessing anxiety-like behaviors in zebrafish is the “novel tank test”. We hypothesized that using deeper tanks in this test would result in greater between-individual variation in behavioral responses and a more ‘repeatable’ assay. New methodsAfter mapping the literature and identifying common behavioral parameters used in analysis, we performed novel tank anxiety tests in both custom-designed ‘tall’ tanks with increased depth and ‘short’ trapezoidal tanks. We compared the repeatability of the behavioral parameters between tall and short tanks and also investigated sex differences. ResultsOverall, regardless of tank depth, almost all behavioral parameters associated with anxiety in zebrafish were significantly repeatable (R = 0.24 to 0.60). Importantly, our tall tanks better captured between-individual differences, resulting in higher repeatability estimates (average repeatability tall tanks: R = 0.46; average repeatability short tanks: R = 0.36) and clearer sex differences. ConclusionsOur assay using tall tanks has advantages over tests based on short tanks which underestimate repeatability. We argue that use of deeper tanks will improve the reliability of behavioral data across studies using novel tank tests for zebrafish. Our results also call for increased attention in designing the most appropriate assay in biomedical and behavioral sciences as current methods may lack the sensitivity to detect subtle, yet important, information, such as between-individual variation, an important component in assessing the reliability of behavioral data.

Experimental study of stress state parameters of short cylindrical reinforced concrete tank

The article presents the application of the calculation method of short reinforced concrete cylindrical tanks as shells of rotation, which work under the action of hydrostatic or uniform load taking into account the edge effect, based on the method of successive approximations. It is proved that the proposed method of successive approximations, used in the calculation of continuous beams and frames, simplifies the calculation of short reinforced concrete cylindrical tanks significantly. General expressions for forces and deformations in a short cylindrical tank as a moment less shell of rotation, from a uniformly distributed load on the upper edge, from a hydrostatic load and from own weights are given. An experimental study of the internal forces arising at the junction of the wall and bottom of the tank during the hinged fixing of the wall and bottom and during rigid fixing, under the action of hydrostatic load and the own weight of the tank are made. The tests were performed both with and without the outer annular steel reinforcement. The possibility of applying the method of successive approximations to the calculation of short cylindrical tanks is analyzed. It is checked whether it is expedient to use this method when solving the problem of stress state of short tanks, by comparing theoretical and experimental results. The limits of use of the method to calculate short cylindrical reinforced concrete tanks are became.

SEISMIC DESIGN EVALUATION OF LIQUID-FILLED STIFFENED STEEL CYLINDRICAL TANKS

This paper aims to estimate dynamic buckling loads of cylindrical liquid storage tanks. Finite element analysis is performed using ANSYS computer program. Twelve different geometries of the cylindrical tanks are analyzed with height to diameter (H/D) ratios of 0.5, 1.0, 1.5, and 2.0 and the diameter to thickness (D/t) ratios of 1000, 1500, and 2000 to cover tall and short cylindrical tanks. The dynamic buckling capacities of cylindrical tanks filled with water up to 90% of their height are investigated in this study. The transient dynamic analysis is performed to find the dynamic buckling loads. Applied dynamic loads in this study are horizontal earthquake excitations in terms of acceleration (g) due to gravity. The transient dynamic analysis results indicate that the dynamic buckling loads decrease when the H/D ratios increase, and the dynamic buckling loads decrease when the D/t ratios increase. Design curves for the cylindrical tanks of various geometries subjected to earthquake accelerations are generated.

Design of a Simple Control Strategy for a Community-size Solar Heating System with a Seasonal Storage

The presented paper focuses on the design of different control strategies of a cold climate community-size solar thermal system located in Finland. The system was designed on TRNSYS software in order to perform dynamic simulation. A solar thermal system operating with various control strategies has been designed with an integrated ground source heat pump and a seasonal borehole storage to provide domestic hot water (DHW) and space heating (SH) for community-size demand. The system has two short term storage tanks, a hot tank and a warm tank. The impact of the considered system solutions on electricity consumption has been evaluated and compared as a function of the different collector control modes and different tank configurations (short term tanks sizes). Results have shown that the proposed system was able to provide a 78-83% renewable energy fraction. Total electricity consumption of the heating system varied by 20% between the best and the worst cases. Furthermore, system performance was better when solar energy was mainly stored in the warm tank. During a 5-year simulation, the annual seasonal storage efficiency improved from 0.23 to 0.31, whereas the heat pump electricity consumption reduced from 57.17 MWh to 45.93 MWh. The demand in winter was met mainly through ground heat and the rest was provided by the heat pump compressor. However, the demand in summer was met almost completely by solar energy.

Comparative Performance of Elevated Isolated Liquid Storage Tanks (With Shaft Staging)

Liquid storage tanks are important components of lifeline and industrial facilities. They are critical elements in water supply scheme and fire fighting system, and extensively used for storage and processing of variety of liquid like material such as petroleum product, liquefied natural gas, chemical fluid and wastage of different forms. In this paper, the seismic response of base isolated cylindrical liquid storage tanks is investigated under real earthquake ground motion. The isolation systems considered is elastomeric bearings (without lead core), the specific objectives of the study are to carry out the comparative performance of the tanks with isolation and without isolation (i.e. Fixed tanks) also to investigate the response of the tanks for varying capacity with varying heights. For this study forty tanks of varying heights such as 8m,10m,11m,11.5m,12.5m,14m,16m with varying capacities of 500kl,265kl,200kl,100kl,50kl are considered. For this a time history analysis has been carried out by using a three time history of varying magnitude with varying peak ground acceleration. It is observed that the base shear of elevated liquid storage tanks supported on shaft is significantly reduced due to isolation. The drift of the tank relation to base of shaft is also significantly reduced due to isolation. The earthquake response of isolated short tanks is relatively more, i.e. Isolation is not effective for stiffer shafts, and however in general, the effectiveness of base isolation is achieved for tall tanks. Although the effectiveness of seismic isolation increases with the increase of bearing flexibility and damping these properties needs to be modified for desired response.

Modelling of vibrations of a liquid filled tank

Modelling of vibrations of a liquid filled tank Kinematic excitations provoke the motion and vibrations of the construction, which in turn considerably affects hydrodynamic loads generated on the walls of liquid cargo tanks. The issues of hydrodynamics also refer to the constructions fixed to the bottom, and those half-immersed, fully immersed, and floating (drilling platforms). They mainly concern ship tanks and oceanotechnical tanks. The theoretical and numerical analysis for long an short tanks, fully or partially filled with liquid has been performed. The determined hydrodynamic loads directly refer to the strength of the tank structure, which provides opportunities for determining the constructional strength of the entire hull. Extremely severe requirements are to be met by tanks used for carrying radioactive liquids, as an extremely high safety level is to be secured on all cargo carriers used in marine and land transport.

An experimental investigation of spin-up from rest of a stratified fluid

We examine the spin-up from rest of a stratified fluid with initial Brunt–Väisälä frequency N bound within a cylindrical container of height 2H and radius R which is set to rotate impulsively with angular speed f/2. Particular attention is given to characterizing the dependence of the form of the resulting flow on the governing parameters. Our experimental study reveals a wealth of flow behaviours and instabilities. In all experiments, the initial phase of motion is marked by the establishment of mixed axisymmetric corner regions fed by radial Ekman transport, a process detailed in Flór et al. (Flór, J.B., Ungarish, M. and Bush, J.W.M., “Spin-up from rest of a stratified fluid: boundary flows”, J. Fluid Mech., 472, 51–82 (2002).). The subsequent evolution of the central vortex depends critically on the Burger number , where is the buoyancy frequency of the central core following the establishment of the corner regions. For B > 1.0, the axisymmetry of the system is retained throughout the spin-up process: the central vortex attains a state of near solid body rotation by the diffusion of vorticity from the sidewalls. For B < 1.0, the central core becomes baroclinically unstable, and its streamlines strained from circles into ellipses. Subsequently, for Nc/f < 1 (and B < 1.0), the symmetry of the central core is broken in a manner reminiscent of the elliptical instability. For short tanks (2H/R < 1), the instability is marked by a simple tip-over of the central core in the laboratory frame that is resisted by the core stratification. For 2H/R > 1, the centreline of the stratified core is deflected into a helical form before the core breaks into a series of stacked vortices. A Burger number criterion, , for the baroclinic instability of the central core is derived and found to be consistent with the experimental observations.

Integration of Poultry with Aquaculture in Seasonal Tank

An experiment was conducted for short-term culture of carps involving marginal farmers in a seasonal tank with area of 15 ha at Budhemanahalli in Bengalore district. A rectangular pen of size 60 m x 22 m was installed in the tank using a close meshed HDPE cloth in a pre-selected area with uniform bottom. A low cost thatched poultry shed of size 10 m x 6 m was constructed within the pen enclosure, perching 2 m above the water surface at full tank level. A total of 260 chicks (Giriraja) of average weight of 200 g were reared in the shed. The pen was stocked with 1500 fingerlings of common carp (av. wt. 5 g) during July. No manuring or feeding was adopted. After rearing period of 80 days, the birds attained an average weight of one kilogram and 182 kg of birds were disposed off. A total of 277 kg of fish was harvested from the pen in 150 days of culture. The size of the fish ranged between 238-350 mm (av. 254 mm) in length and 260-840 g (av. 346.6 g) in weight. The results indicated the feasibility of integrating aquaculture with poultry rearing in short seasonal tanks or watersheds.

Imperfection sensitivity to elastic buckling of wind loaded open cylindrical tanks

This paper considers the buckling and post-buckling behavior of empty metal storage tanks under wind load. The structures of such tanks may be idealized as cantilever cylindrical shells, and the structural response is investigated using a computational model. The modeling employs a doubly curved finite element based on a theory by Simo and coworkers, which is capable of handling large displacements and plasticity. Buckling results for tanks with four different geometric relations are presented to consider the influence of the ratios between the radius and the height of the shell (R/L), and between the radius and the thickness (R/t). The studies aim to clarify the differences in the shells regarding their imperfection-sensitivity. The results show that thin-walled short tanks, with R/L = 3, display high imperfection sensitivity, while tanks with R/L = 0.5 are almost insensitive to imperfections. Changes in the total potential energy of tanks that would buckle under the same high wind pressures are also considered.

Finite element simulations of fully non‐linear interaction between vertical cylinders and steep waves. Part 2: numerical results and validation

AbstractIn Ma, Wu, Eatock Taylor [Finite element simulation of fully non‐linear interaction between vertical cylinders and steep waves. Part 1: methodology and numerical procedure. International Journal for Numerical Methods in Fluids 2001], designated Part 1 hereafter, we have developed the methodology and solution procedure for simulating the three‐dimensional interaction between fixed bodies and steep waves based on a finite element method (FEM). This paper provides extensive numerical results and validation. The effectiveness of the radiation condition is investigated by comparing the results from short and long tanks; the accuracy of the computed data is confirmed through comparison with analytical solutions. The adopted mathematical model is also validated by comparing the obtained numerical results with experimental data. Various test cases, including non‐linear bichromatic and irregular waves and the interactions between waves and one or two cylinders, are analysed. Copyright © 2001 John Wiley &amp; Sons, Ltd.

Axisymmetric bending solution of shells of revolution by the generalized differential quadrature rule

A generalized differential quadrature rule (GDQR) proposed recently by the authors is applied here to obtain the axisymmetric bending solution of shells of revolution, which includes both long and short cylinders and storage tanks with stepped wall thickness. The boundary conditions for long cylinders are simplified in a practical way. The analysis of storage tank with stepped wall thickness is formulated with the aid of domain decomposition, and the compatibility conditions are expressed explicitly. The annular bottom plate and the stepped tank shell are considered as part of the whole. The engineering design of the annular bottom plate and the concrete ring wall is discussed considering an accurate assumption for the interaction between the bottom plate and the foundation. Examples are presented to demonstrate the efficiency of the GDQR.

Design development of the SCDTL structure for the TOP linac

The Side Coupled Drift Tube Linac (SCDTL) is an attractive 3 GHz accelerating structure composed of short DTL tanks coupled together by side coupling cavities, in the course of development of the 200 MeV proton linear accelerator for proton therapy planned for the Terapia Oncologica con Protoni (TOP) program of the Italian National Institute of Health (Istituto Superiore di Sanità, ISS). The TOP Linac will be used to boost to 70 MeV the 7 MeV proton beam from a linac injector. Our main concern is to investigate in detail the characteristics of the structure in terms of RF properties of the accelerating mode, like longitudinal and transverse shunt impedance and quality factor, and of the other modes that cause the origin of the tank dispersion curve, in order to stabilize the behaviour under operating conditions. Calculations performed with the computer three-dimensional (3D) codes MAFIA and SOPRANO on the smallest unit of the system (a single DTL tank without coupling cavities) and experimental measurements made on a prototype have shown good agreement. Two possible supporting stem configurations (single stem and two stems 180° apart for each drift tube) were examined and a comparison of the results in both cases are discussed.

Buckling of short tanks due to hurricanes

Buckling of thin-walled, short tanks, under severe wind conditions, is investigated using numerical methods. The shells are representative of cylindrical tanks that failed during hurricane Marilyn in the Caribbean islands in 1995, with radius/thickness ratio of 1900 and radius/height ratio of 5. Several models are employed to study instability: bifurcation buckling from a linear fundamental path, nonlinear analysis of imperfect tank, and dynamic response. Wind is modeled using several pressure distributions in the circumferential direction, and the results are compared with those due to axisymmetric pressure. The results show that for the present very thin-walled short tanks, bifurcation buckling produces good estimates of the critical state; however, the structure is imperfection sensitive and this load is reduced in the order of 30–50%.

Collapse loads of reinforced concrete cylindrical water tanks using limit analysis approach

Evaluation of the margin of safety against collapse of reinforced concrete cylindrical water tanks requires knowledge about the load carrying capacity of the tanks. The limit analysis procedure can be used to estimate the collapse loads of cylindrical tanks. In this paper, determination of the collapse loads of reinforced concrete circular cylindrical water tanks, having varying reinforcement along the height, by applying the limit analysis approach is discussed. The relevant mathematical formulations and the details of the computer program TANK developed for estimating the collapse loads of short, medium height and long cylindrical tanks are presented. The formulations presented are general in nature and different distributions of hoop reinforcement along the height of the tank wall can be considered. The results obtained using this program are found to be in good agreement with those reported in the literature. Numerical results for example problems with different hoop reinforcement distributions are given.