Experimental analysis of the feasibility of polydisperse droplet water flow using at fire extinguishing

Introduction. A number of problems accompany the development of new extinction methods applicable on the premises of buildings and structures and the use of advanced fire extinguishing agents. Subject-specific studies are needed to solve these problems. They include the identification of general principles of fire extinguishing efficiency and further development of the optimal mode of application of firefighting agents. The purpose of this work is the theoretical assessment of fire extinction mechanisms involving the water mist applied to combustible liquids. The objectives to be accomplished include the equations based on the mass/energy conservation laws and derived for flame zones with account taken of the water mist applied; the assessment of the water flow rate for different combustion mechanisms; comparison of assessment results with experimental data obtained in the process of extinguishing model fire seats that have burning combustible fluids.Methods of analysis. The calculations involve the equations based on the mass/energy conservation laws and derived for flame zones above the surface of combustibles.Research results. The author analyzes two fire extinguishing mechanisms that contribute to the suppression of burning in the flame zone: 1) the attainment of the value of mass concentration of water vapour that reaches the lower concentration limit of combustion of the combustible mixed gas (oxygen reduction); 2) cooling combustible mixed gas in the flame zone by evaporating water until the flash point temperature of combustible vapour is reached.Conclusions: Equations based on mass/energy conservation laws were derived for flame zones, formed in the course of combustion of flammable liquids, with account taken of a jet of water mist. Water flow rates needed for the implementation of various extinguishing mechanisms were analyzed using the proposed equations. Theoretical results were compared with the experimental data obtained in the process of using water mist to extinguish model fire seats that contain combustible fluids.

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Experimental Analysis of SMART Scrubbing System with the Principle of Dynamic Precipitation

International Journal of Engineering & Technology ◽

10.14419/ijet.v7i4.35.22753 ◽

2018 ◽

Vol 7 (4.35) ◽

pp. 317

Author(s):

Nirvenesh Ravindran ◽

Hasril Hasini

Keyword(s):

Experimental Investigation ◽

Water Flow ◽

Flow Rate ◽

Experimental Analysis ◽

Dust Concentration ◽

Processing Plant ◽

Dynamic Precipitation ◽

Flow Rates ◽

Model Experiments ◽

Process Line

This paper presents an experimental investigation of a SMART scrubbing system in sugar processing plant. The objectives are to address the problem and develop new technique to increase the efficiency and eliminate sugar sludge production downstream of process line. The SMART scrubbing effect of water with the principal of dynamic precipitation was conducted on-site with calculated flow rate, which simulates the SMART scrubbing system. The on-site and scaled-down model experiments measure the upstream and downstream dust concentration and processes the flow rate of water required to counter the dust concentration based on the feedback flow. The investigation was conducted with a steady airflow of 6 m3/s with variation of water flow rates. The result of the on-site studies shows an excellent increase in average and maximum efficiencies of 98.77% and 99.3% respectively.

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Odontocete suction feeding: Experimental analysis of water flow and head shape

Journal of Morphology ◽

10.1002/jmor.10486 ◽

2006 ◽

Vol 267 (12) ◽

pp. 1415-1428 ◽

Cited By ~ 43

Author(s):

Alexander J. Werth

Keyword(s):

Water Flow ◽

Experimental Analysis ◽

Head Shape ◽

Suction Feeding

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Experimental Analysis of Water Flow in Aquaponics Fish Tanks

Volume 3A: Fluid Applications and Systems ◽

10.1115/ajkfluids2019-5481 ◽

2019 ◽

Author(s):

Hannah Thomas ◽

Danielle Coombs ◽

Ivaylo Nedyalkov ◽

Todd Guerdat

Keyword(s):

Numerical Simulations ◽

Water Flow ◽

Experimental Analysis ◽

Local Community ◽

Small Scale ◽

Acoustic Doppler Velocimeter ◽

Operational Costs ◽

Initial Cost ◽

Fish Tank ◽

Fish Tanks

Abstract Aquaponic systems are a combination of hydroponics, growing plants in water, and aquaculture, growing of fish. The two subsystems are connected so that the water circulating between the two, transfers the waste from the fish tank to the plants, where the plants take in nutrients. The water is filtered by the plants and is recirculated back into the fish tank. Small-scale aquaponic systems are of particular interest, as they are appropriate for rural and developing locations to harvest both plants and fish for a local community. To improve the level of sustainability, the flow within the fish tank needs to be better understood since most of the power required to operate an aquaponic system is used by the fish-tank pump. The shape of the fish tank is of importance for the flow in the tank and the initial cost of the tank. In this work, the flow in a 2 m × 2 m square fish tank with curved corners was studied experimentally with a Vectrino Acoustic Doppler Velocimeter. Two inlet configurations were studied and compared to each other — inlets at each corner of the tank, and inlets at two of the corners of the tank. The results suggest that good recirculation can be achieved with the two inlet locations. The present work can be used for evaluating numerical simulations of the flow in the tank. The ultimate goal of the study is to develop an inlet-design configuration which minimizes initial and operational costs of the small-scale aquaponic system.

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Assessment of extinguishing efficiency of hybrid system using water mist and inert gas during class A fires

MATEC Web of Conferences ◽

10.1051/matecconf/201824700013 ◽

2018 ◽

Vol 247 ◽

pp. 00013

Author(s):

Jerzy Gałaj ◽

Tomasz Drzymała

Keyword(s):

Water Flow ◽

Hybrid System ◽

New Technology ◽

Water Mist ◽

International Standards ◽

Inert Gas ◽

Pipe System ◽

Class A ◽

Fire Extinguishing ◽

The Impact

Fixed hybrid fire extinguishing system, a new technology used in fire protection all over the world in the last years, was discussed. A four-head twin pipe system supplied with water mist and inert gas (air or nitrogen) was applied. A pile of 50 pine wood boards was used as a combustible material (class A fire). It was located in the corner of the compartment while the nozzles were mounted symmetrically in the centre (volume suppression). The extinguishing processes differing in the proportion of water mist to gas were analysed. The extinguishing time was taken as the most important parameter indicating the extinguishing efficiency. The impact of water flow on extinguishing process was discussed. The clear dependence of extinguishing time on the water/gas ratio was proven. The best performance of the hybrid system at water flow 3 dm3/min and nitrogen as inert gas was observed. The results obtained during experiments can be useful in developing new international standards e.g. NFPA.

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Effect of verapamil on cytoplasmic distribution of granules and microfilaments in amphibian urinary bladder

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100103681 ◽

1988 ◽

Vol 46 ◽

pp. 324-325

Author(s):

A.J. Mia ◽

L.X. Oakford ◽

T. Yorio

Keyword(s):

Urinary Bladder ◽

Water Flow ◽

Morphological Changes ◽

Granular Cell ◽

Cytosolic Calcium ◽

Calcium Storage ◽

Amphibian Urinary Bladder ◽

Vesicular Membrane ◽

High Concentrations ◽

Cytoskeletal System

The amphibian urinary bladder has been used as a ‘model’ system for studies of the mechanism of action of antidiuretic hormone (ADH) in stimulating transepithelial water flow. The increase in water permeability is accompanied by morphological changes that include the stimulation of apical microvilli, mobilization of microtubules and microfilaments and vesicular membrane fusion events . It has been shown that alterations in the cytosolic calcium concentrations can inhibit ADH transmembrane water flow and induce alterations in the epithelial cell cytomorphology, including the cytoskeletal system . Recently, the subapical granules of the granular cell in the amphibian urinary bladder have been shown to contain high concentrations of calcium, and it was suggested that these cytoplasmic constituents may act as calcium storage sites for intracellular calcium homeostasis. The present study utilizes the calcium antagonist, verapamil, to examine the effect of calcium deprivation on the cytomorphological features of epithelial cells from amphibian urinary bladder, with particular emphasis on subapical granule and microfilament distribution.

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