Improving Keeping for Octopuses by Testing Different Escape-Proof Designs on Tanks for “Big Blue Octopus” (Octopus cyanea)

Octopus cyanea has a wide range of natural distribution and is interesting for scientific research. However, unlike Octopus vulgaris, the species is poorly studied, and few data exist on best practices for keeping them. One of the most common reasons for losing octopuses in human care is their ability to escape from holding tanks. Adult Octopus cyanea (n = 33) were locally collected in Okinawa throughout the year. All animals were housed at the laboratory facilities at the Marine Station of the Okinawa institute of Science and Technology. Animals were kept in a flow-through saltwater system in three different types of holding tanks ranging from 550 L to 600 L tanks or in 2000 L tanks, all with an environment enriched with clay pots or natural rocks as dens. They were fed a daily diet of dead fish or live or dead crustaceans ad libitum. To characterize the effectiveness of different keeping conditions, we compared escape attempts and non-natural deaths during the animals’ time under human care. We found that two types of tanks, the 600 L transparent acrylic glass tanks with weighted lids and the 2000 L tanks with synthetic grass lined walls, had significantly fewer escapes than the 550 L tanks.

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Krypton 85 myocardial blood flow: precordial scintillation versus coronary sinus sampling

American Journal of Physiology-Legacy Content ◽

10.1152/ajplegacy.1965.209.4.705 ◽

1965 ◽

Vol 209 (4) ◽

pp. 705-710 ◽

Cited By ~ 34

Author(s):

Michael D. Klein ◽

Lawrence S. Cohen ◽

Richard Gorlin

Keyword(s):

Blood Flow ◽

Myocardial Blood Flow ◽

Coronary Sinus ◽

Human Subjects ◽

Radioactive Decay ◽

Empirical Correction ◽

Wide Range ◽

Actual Flow ◽

Flow Through ◽

High Degree

Myocardial blood flow in human subjects was assessed by comparative simultaneous measurement of krypton 85 radioactive decay from coronary sinus and precordial scintillation. Empirical correction of postclearance background from precordial curves yielded a high degree of correlation between flows derived from the two sampling sites (r = .889, P < .001). Comparison of left and right coronary flows in nine subjects revealed similarity in flow through the two vessels over a wide range of actual flow values (r = .945, P < .001).

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Development of Permeability Models for Saturated Fluid Flow across Arrays of Fibre Clusters

Advanced Composites Letters ◽

10.1177/096369350201100303 ◽

2002 ◽

Vol 11 (3) ◽

pp. 096369350201100

Author(s):

E.M. Gravel ◽

T.D. Papathanasiou

Keyword(s):

Analytical Models ◽

Dual Porosity ◽

Hydraulic Permeability ◽

Fibrous Media ◽

Fibre Bundles ◽

Hexagonal Packing ◽

Composites Manufacturing ◽

Starting Point ◽

Wide Range ◽

Flow Through

Dual porosity fibrous media are important in a number of applications, ranging from bioreactor design and transport in living systems to composites manufacturing. In the present study we are concerned with the development of predictive models for the hydraulic permeability ( Kp) of various arrays of fibre bundles. For this we carry out extensive computations for viscous flow through arrays of fibre bundles using the Boundary Element Method (BEM) implemented on a multi-processor computer. Up to 350 individual filaments, arranged in square or hexagonal packing within bundles, which are also arranged in square of hexagonal packing, are included in each simulation. These are simple but not trivial models for fibrous preforms used in composites manufacturing – dual porosity systems characterised by different inter- and intra-tow porosities. The way these porosities affect the hydraulic permeability of such media is currently unknown and is elucidated through our simulations. Following numerical solution of the governing equations, ( Kp) is calculated from the computed flowrate through Darcy's law and is expressed as function of the inter- and intra-tow porosities (φ, φt) and of the filament radius ( Rf). Numerical results are also compared to analytical models. The latter form the starting point in the development of a dimensionless correlation for the permeability of such dual porosity media. It is found that the numerically computed permeabilities follow that correlation for a wide range of φ i, φt and Rf.

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On LES Methods Applied to Seal Geometries

Volume 8: Turbomachinery, Parts A, B, and C ◽

10.1115/gt2012-68840 ◽

2012 ◽

Cited By ~ 2

Author(s):

James Tyacke ◽

Richard Jefferson-Loveday ◽

Paul Tucker

Keyword(s):

Maximum Error ◽

Labyrinth Seal ◽

Navier Stokes ◽

Final Solution ◽

Complex Flow ◽

Eddy Simulation ◽

Wide Range ◽

Large Eddy ◽

Rans Models ◽

Flow Through

Nine Large Eddy Simulation (LES) methods are used to simulate flow through two labyrinth seal geometries and are compared with a wide range of Reynolds-Averaged Navier-Stokes (RANS) solutions. These involve one-equation, two-equation and Reynolds Stress RANS models. Also applied are linear and nonlinear pure LES models, hybrid RANS-Numerical-LES (RANS-NLES) and Numerical-LES (NLES). RANS is found to have a maximum error and a scatter of 20%. A similar level of scatter is also found among the same turbulence model implemented in different codes. In a design context, this makes RANS unusable as a final solution. Results show that LES and RANS-NLES is capable of accurately predicting flow behaviour of two seals with a scatter of less than 5%. The complex flow physics gives rise to both laminar and turbulent zones making most LES models inappropriate. Nonetheless, this is found to have minimal tangible results impact. In accord with experimental observations, the ability of LES to find multiple solutions due to solution non-uniqueness is also observed.

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CFD Simulation of Fluid Flow Through Porous Media: Application to Decomposed Gases Flow Through Foam Pattern in Lost Foam Casting

Materials ◽

10.1115/imece2003-43500 ◽

2003 ◽

Cited By ~ 1

Author(s):

Sayavur I. Bakhtiyarov ◽

Ruel A. Overfelt

Keyword(s):

Cfd Simulation ◽

Reynolds Numbers ◽

Phase Flow ◽

Flow Through Porous Media ◽

Foam Material ◽

Element Analysis ◽

Wide Range ◽

Flow Through ◽

Foam Pattern ◽

Lost Foam

Numerical simulation of decomposed gases through foam pattern was conducted using finite element analysis. A new kinetic model is proposed for gaseos phase flow between molten metal and foam material. The computations were performed for a wide range of Reynolds numbers. The results of the simulations are compared with the experiemental data obtained in this study.

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Combined numerical and experimental study of microstructure and permeability in porous granular media

10.5194/se-2019-199 ◽

2020 ◽

Author(s):

Philipp Eichheimer ◽

Marcel Thielmann ◽

Wakana Fujita ◽

Gregor J. Golabek ◽

Michihiko Nakamura ◽

...

Keyword(s):

Fluid Flow ◽

Numerical Simulations ◽

Granular Media ◽

Large Scale ◽

Earth Science ◽

Numerical Models ◽

Effective Porosity ◽

Flow Properties ◽

Wide Range ◽

Flow Through

Abstract. Fluid flow on different scales is of interest for several Earth science disciplines like petrophysics, hydrogeology and volcanology. To parameterize fluid flow in large-scale numerical simulations (e.g. groundwater and volcanic systems), flow properties on the microscale need to be considered. For this purpose experimental and numerical investigations of flow through porous media over a wide range of porosities are necessary. In the present study we sinter glass bead media with various porosities. The microstructure, namely effective porosity and effective specific surface, is investigated using image processing. We determine flow properties like hydraulic tortuosity and permeability using both experimental measurements and numerical simulations. By fitting microstructural and flow properties to porosity, we obtain a modified Kozeny-Carman equation for isotropic low-porosity media, that can be used to simulate permeability in large-scale numerical models. To verify the modified Kozeny-Carman equation we compare it to the computed and measured permeability values.

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An efficient analytic approach for solving Hiemenz flow through a porous medium of a non-Newtonian Rivlin-Ericksen fluid with heat transfer

Nonlinear Engineering ◽

10.1515/nleng-2017-0160 ◽

2018 ◽

Vol 7 (4) ◽

pp. 287-301

Author(s):

Kourosh Parand ◽

Yasaman Lotfi ◽

Jamal Amani Rad

Keyword(s):

Heat Transfer ◽

Porous Medium ◽

Homotopy Analysis Method ◽

Nonlinear Differential Equations ◽

Analytic Method ◽

Analysis Method ◽

Wide Range ◽

Hiemenz Flow ◽

Homotopy Analysis ◽

Flow Through

AbstractIn the present work, the problem of Hiemenz flow through a porous medium of a incompressible non-Newtonian Rivlin-Ericksen fluid with heat transfer is presented and newly developed analytic method, namely the homotopy analysis method (HAM) is employed to compute an approximation to the solution of the system of nonlinear differential equations governing the problem. This flow impinges normal to a plane wall with heat transfer. It has been attempted to show capabilities and wide-range applications of the homotopy analysis method in comparison with the numerical method in solving this problem. Also the convergence of the obtained HAM solution is discussed explicitly. Our reports consist of the effect of the porosity of the medium and the characteristics of the Non-Newtonian fluid on both the flow and heat.

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Design Study of Condenser and Circulation System

Marine Technology and SNAME News ◽

10.5957/mt1.1971.8.2.159 ◽

1971 ◽

Vol 8 (02) ◽

pp. 159-185

Author(s):

Sterling A. Fielding

Keyword(s):

Life Cycle Cost ◽

Circulation System ◽

Life Cycle Cost Analysis ◽

Trade Routes ◽

Wide Range ◽

Flow Through ◽

Drawing Board ◽

Design Characteristics ◽

Guidance Study ◽

Design Guidance

Economical performance of steam condensers is controlled largely from the drawing board and computer room; not by the ship's crew. The design characteristics of the condenser and circulation system determine condenser performance, except for the effect of tube cleanliness. Seawater for the circulation system varies from 35 to 82.5 F over a wide range of commercial trade routes. However, on certain routes the variation is from 35 to 60 F; on others 65 to 82.5 F. A survey was made of seawater temperatures for selected trade routes, and results plotted graphically for design guidance. Study has been directed toward design of condensers and circulation systems for special-purpose and for universal-type ship operations. A series pump-scoop arrangement is proposed to provide favorable control of flow through condenser. Variations in condenser and circulation system design are evaluated by a life-cycle cost analysis. A computer program for calculating condenser design characteristics, for checking condenser performance, and for analyzing scoop performance is appended.

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Advances in Fisheries Bioengineering

Advances in Fisheries Bioengineering ◽

10.47886/9781934874028.ch14 ◽

2008 ◽

Keyword(s):

Common Carp ◽

Striped Bass ◽

Flow Rate ◽

Lepomis Macrochirus ◽

Osmerus Mordax ◽

Rainbow Smelt ◽

Test Species ◽

Wide Range ◽

Flow Through ◽

Pair Wise Comparison

Abstract.—Aquatic Filter Barrier (AFB) is a permeable fabric material used to reduce the entrainment of ichthyoplankton at water intakes. To determine the potential for this material to protect a wide range of species, we evaluated the retention and survival of the early life stages of common carp Cyprinus carpio, rainbow smelt Osmerus mordax, white sucker Catostomus commersonii, striped bass Morone saxatilis, and bluegill Lepomis macrochirus exposed to AFB fabric in the laboratory. Twelve flow-through testing apparatuses were used in a closed-loop system to evaluate two flow rates (0.04 L/min/cm2) and 0.08 L/min/cm2) and three sizes of fabric perforation (0.5, 1.0, and 1.5 mm) with each species. The results indicate that, with one exception (pair-wise comparison of bluegill survival between 1.0-mm and 1.5- mm perforations; p = 0.0481), survival of organisms was not significantly correlated (p ≤ 0.05) to either flow rate or perforation size. Retention of organisms decreased significantly with increasing flow rate for one species of fish (pair-wise comparison of rainbow smelt between 0.04 and 0.08 L/min/cm2; p = 0.0084). In addition, larger perforation sizes resulted in significant decreases in retention for three of the test species (common carp, rainbow smelt, and striped bass; p ≤ 0.05). Consequently, the potential effectiveness AFB material is reduced by the use of larger perforation sizes. Provided that the material can be maintained and perforation sizes remain small (0.5 mm), AFB should prevent the entrainment of the majority of the organisms of the species tested in the laboratory.

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Performance Study of a Mixed Flow Impeller Covering an Unsteady Flow Field

Proceedings of the Institution of Mechanical Engineers Part A Journal of Power and Energy ◽

10.1243/pime_proc_1992_206_015_02 ◽

1992 ◽

Vol 206 (2) ◽

pp. 83-93 ◽

Cited By ~ 6

Author(s):

S Sarkar

Keyword(s):

Axial Flow ◽

Rotating Stall ◽

Operating Conditions ◽

Performance Study ◽

Mixed Flow ◽

Pump Impeller ◽

Wide Range ◽

Reversal Flow ◽

Flow Through ◽

Flow Pump

The results presented here are part of a detailed programme measuring the aerodynamics of a high specific speed mixed flow pump impeller over a wide range of operating conditions, including its behaviour in the unsteady stalled regime. The aim is to elucidate the physics of the flow through such an impeller. The noticeable features are the formation of part-span rotating stall cells having no periodicity and organized structure at reduced flow and also the shifting positions of reversal flow pockets as the flowrate changes. Measurements of loss and its variation with span-wise positions and flowrates enable the variation of local efficiency to be determined. The overall flow picture is similar to that expected in an axial flow impeller, though the present impeller displays a narrow stall hysteresis loop almost right through its operating range.

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Extended Stokes series: laminar flow through a loosely coiled pipe

Journal of Fluid Mechanics ◽

10.1017/s0022112078001032 ◽

1978 ◽

Vol 86 (1) ◽

pp. 129-145 ◽

Cited By ~ 86

Author(s):

Milton Van Dyke

Keyword(s):

Laminar Flow ◽

Flow Speed ◽

Square Root ◽

Mean Flow ◽

Dean Number ◽

Curvature Ratio ◽

Wide Range ◽

Square Root Singularity ◽

Flow Through ◽

The One

Dean's series for steady fully developed laminar flow through a toroidal pipe of small curvature ratio has been extended by computer to 24 terms. Analysis suggests that convergence is limited by a square-root singularity on the negative axis of the square of the Dean number. An Euler transformation and extraction of the leading and secondary singularities at infinity render the series accurate for all Dean numbers. For curvature ratios no greater than$\frac{1}{250} $, experimental measurements of the laminar friction factor agree with the theory over a wide range of Dean numbers. In particular, they confirm our conclusion that the friction in a loosely coiled pipe grows asymptotically as the one-quarter power of the Dean number based on mean flow speed. This contradicts a number of incomplete boundary-layer analyses in the literature, which predict a square-root variation.

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