Method of the boiler room ventilation system efficiency experimental determination

The issue of the normative air exchange ensuring in the premises of the boiler houses is extremely important. The article presents the results of theoretical and experimental studies of air velocity determination in the distribution of air by round and compact jets in the boiler room. Graphical and analytical dependences are given. The research results substantiate the higher accuracy of the average air flow velocity determination in small boiler rooms. The aim of the work is to develop a method for experimental determination of the efficiency of the ventilation system in the boiler room; to increase of the accuracy of the average velocity determination of the round and the compact air jets in the plane of the supply nozzle to ensure the normative air exchange of the boiler room and to substantiate of the calculation method. The characteristics and patterns of development of round and compact air jets in the premises are established and the calculated dependences are obtained. The unitless integral air velocity for the round and compact air jets in the boiler room is established. Calculation dependences for determining of the air flow rate in the boiler room have been obtained. It is substantiated that the application of the proposed method will significantly increase the accuracy of air exchange determination in the boiler rooms to ensure the required value in accordance with regulatory requirements. Also it is substantiated that to obtain satisfactory experimental results on speed measurements in the boiler room, it is necessary to measure the speed in the center of the supply nozzle several times with maximum accuracy. Then multiply the result by the relative average velocity: for a round jet vav = 0,26 and for a compact jet – vav = 0,2025. The obtained results allow to avoid a significant error (19 %) in determining the required air exchange ventilation of the boiler room. Recommendations for the practical determination of the calculated values to ensure proper ventilation of the boiler rooms are given.

Download Full-text

Method of the boiler room ventilation system efficiency experimental determination

Energy and automation ◽

10.31548/energiya2020.06.071 ◽

2020 ◽

pp. 71-81

Author(s):

O. Voznyak ◽

◽

Yu. Yurkevych ◽

M. Kasynets ◽

N. Spodyniuk ◽

...

Keyword(s):

Experimental Determination ◽

Ventilation System ◽

Experimental Studies ◽

Regulatory Requirements ◽

Air Jets ◽

Boiler Room ◽

Room Ventilation System ◽

Air Flow Velocity ◽

Air Exchange

Download Full-text

The Results of Experimental Determination of Air Output and Velocity of Flow in Double Skin Facades

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.725-726.93 ◽

2015 ◽

Vol 725-726 ◽

pp. 93-99 ◽

Cited By ~ 4

Author(s):

Mikhail Petrichenko ◽

Nikolai Vatin ◽

Darya Nemova ◽

Vyacheslav Olshevskiy

Keyword(s):

Experimental Determination ◽

Average Velocity ◽

Air Flow ◽

Air Gap ◽

Double Skin ◽

Double Skin Facades ◽

New Buildings

Double skin facades very popular in this time. They are applied for construction of new buildings and for reconstruction. This paper to try to consider the main problems which appear during the work with the double skin facades. In paper are presented dependence of average velocity of air flow as functions from the geometrical sizes of the ventilated air gap of double skin facades and air output as functions from the geometrical sizes of air gap. This dependences are received experimentally. The received dependences can be used at design of double skin facades for the purpose of obtaining the optimum sizes of an air gap.

Download Full-text

EXPERIMENTAL STUDIES OF REINFORCED CONCRETE STRUCTURES WITH CROSS-SHAPED SPATIAL CRACK UNDER TORSION WITH BENDING

Building and reconstruction ◽

10.33979/2073-7416-2020-92-6-13-25 ◽

2020 ◽

Vol 92 (6) ◽

pp. 13-25

Author(s):

Vl.I. KOLCHUNOV ◽

◽

A.I. DEMYANOV ◽

M.M. MIHAILOV ◽

◽

...

Keyword(s):

Reinforced Concrete ◽

Experimental Determination ◽

Calculation Method ◽

Experimental Studies ◽

Concrete Structures ◽

Design Parameters ◽

Reinforced Concrete Structures ◽

Experimental Scheme

The article offers a method and program for experimental studies of reinforced concrete structures with cross-shaped spatial crack under torsion with bending, the main purpose of which is to check the design assumptions and experimental determination of the design parameters of the proposed calculation method. The conducted experimental studies provide an opportunity to test the proposed calculation apparatus and clarify the regularities for determining deflections, angles of rotation of extreme sections, and stresses in the compressed zone of concrete. For analysis, the article presents a typical experimental scheme for the formation and development of cracks in the form of a sweep, as well as characteristic graphs of the dependence of the angles of rotation of end sections.

Download Full-text

Air Flow Straighteners’ Application to Reduce the Power Consumption of Exhaust Ventilation Schemes

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.875.137 ◽

2018 ◽

Vol 875 ◽

pp. 137-140 ◽

Cited By ~ 5

Author(s):

Valery N. Azarov ◽

Natalia M. Sergina ◽

I.V. Stefanenko

Keyword(s):

Power Consumption ◽

Air Flow ◽

Ventilation System ◽

Aerodynamic Resistance ◽

Experimental Studies ◽

Swirling Flows ◽

Dust Collector ◽

Exhaust Ventilation ◽

Outlet Pipe ◽

Ventilation Systems

It was proposed to use air flow screw straightened units in outlet pipe of the dust collectors to reduce the aerodynamic resistance of exhaust ventilation systems. It is allowed to decrease power consumption for their maintenance operation consequently. The article describes the results of experimental studies to evaluate its effectiveness by applying the tangential screw straightened unit within ventilation system. The obtained results showed that the use of this device allows reducing the aerodynamic resistance of the cyclone by 14.6%, and for counter-swirling flows’ dust collector (CSFC) by 17.2-23.6%. It was found that meanings of the aerodynamic resistance depend on value the share proportion of the flow entering into lower CSFC apparatus’ input.

Download Full-text

Experimental Studies of Force Systems on Steered Agricultural Tyres

Proceedings of the Institution of Mechanical Engineers Automobile Division ◽

10.1243/pime_auto_1966_181_019_02 ◽

1966 ◽

Vol 181 (1) ◽

pp. 133-148 ◽

Cited By ~ 1

Author(s):

P. A. Taylor ◽

R. Birtwistle

Keyword(s):

Experimental Determination ◽

Experimental Studies ◽

Soil Surface ◽

Slip Angle ◽

Vertical Load ◽

Force Systems

The paper reports the experimental determination of the force systems acting on free-rolling 7–50 times 16 agricultural tyres, measured with a six-component suspension of the test wheel. Multivariate experimentation techniques were used involving five variables: slip angle, camber, vertical load, tyre pattern and land or furrow operation. The results are presented as three force and three moment components; other methods of representation are discussed briefly. Although the side or cornering force depends on many factors, particularly the soil surface, and is therefore difficult to predict, it is suggested that the draught force (i.e. resistance in the direction of motion) can be expressed as a function of slip for all surfaces.

Download Full-text

Conjugate-Mode Heat Transfer from a Module on the Base of a Parallel-Plate Channel to Forced Convective Air Flow. Experimental Determination of Macroscopic Thermal Conductance.

TRANSACTIONS OF THE JAPAN SOCIETY OF MECHANICAL ENGINEERS Series B ◽

10.1299/kikaib.61.1070 ◽

1995 ◽

Vol 61 (583) ◽

pp. 1070-1077 ◽

Cited By ~ 2

Author(s):

Sang Hee Park ◽

Wataru Nakayama

Keyword(s):

Heat Transfer ◽

Experimental Determination ◽

Parallel Plate ◽

Air Flow ◽

Thermal Conductance ◽

Plate Channel

Download Full-text

Influence of Wind on Air Movement in a Free-Stall Barn During the Summer Period / Wpływ wiatru na ruch powietrza w oborze wolnostanowiskowej w okresie letnim

Annals of Animal Science ◽

10.2478/v10220-012-0063-x ◽

2013 ◽

Vol 13 (1) ◽

pp. 109-119 ◽

Cited By ~ 2

Author(s):

Piotr Herbut ◽

Sabina Angrecka ◽

Grzegorz Nawalany

Keyword(s):

Natural Ventilation ◽

Air Flow ◽

Ventilation System ◽

Air Velocity ◽

Summer Period ◽

Air Masses ◽

Air Movement ◽

Microclimatic Conditions ◽

Hot Weather ◽

Different Levels

Abstract Use of natural ventilation in the barn should lead to optimal microclimatic conditions over the entire space. In the summer, especially during hot weather, higher air velocity cools cows, which helps to avoid heat stress. The paper presents the results of studies on the evolution of air movement in a modernized free-stall barn of the Fermbet type with the natural ventilation system during the summer period. Based on measurements of velocity and direction of air flow (inside and outside the barn) and observations of smoke indicator, the movement of air masses in different parts of the barn was identified. Significant variations of air flow at different levels of the barn were found. These differences deviate from the accepted patterns of natural ventilation, which can be found in the literature. The range of a draught and stagnant air along with the conditions in which they are built was determined. On this basis, recommendations regarding the location of barns on the plots and the improvement of ventilation in summer were made.

Download Full-text

Experimental Investigation of the Air Exchange Effectiveness of Push-Pull Ventilation Devices

Energies ◽

10.3390/en13215817 ◽

2020 ◽

Vol 13 (21) ◽

pp. 5817

Author(s):

Sven Auerswald ◽

Carina Hörberg ◽

Thibault Pflug ◽

Jens Pfafferott ◽

Constanze Bongs ◽

...

Keyword(s):

Heat Dissipation ◽

Residential Buildings ◽

Air Flow ◽

Operation Mode ◽

Ventilation System ◽

Field Measurements ◽

Gas Analysis ◽

Decentralised Systems ◽

Set Up ◽

Air Exchange

The increasing installation numbers of ventilation units in residential buildings are driven by legal objectives to improve their energy efficiency. The dimensioning of a ventilation system for nearly zero energy buildings is usually based on the air flow rate desired by the clients or requested by technical regulations. However, this does not necessarily lead to a system actually able to renew the air volume of the living space effectively. In recent years decentralised systems with an alternating operation mode and fairly good energy efficiencies entered the market and following question was raised: “Does this operation mode allow an efficient air renewal?” This question can be answered experimentally by performing a tracer gas analysis. In the presented study, a total of 15 preliminary tests are carried out in a climatic chamber representing a single room equipped with two push-pull devices. The tests include summer, winter and isothermal supply air conditions since this parameter variation is missing till now for push-pull devices. Further investigations are dedicated to the effect of thermal convection due to human heat dissipation on the room air flow. In dependence on these boundary conditions, the determined air exchange efficiency varies, lagging behind the expected range 0.5 < εa < 1 in almost all cases, indicating insufficient air exchange including short-circuiting. Local air exchange values suggest inhomogeneous air renewal depending on the distance to the indoor apertures as well as the temperature gradients between in- and outdoor. The tested measurement set-up is applicable for field measurements.

Download Full-text

Air flow characteristics of a room with air vortex diffuser

MATEC Web of Conferences ◽

10.1051/matecconf/201824002002 ◽

2018 ◽

Vol 240 ◽

pp. 02002 ◽

Cited By ~ 2

Author(s):

Marek Borowski ◽

Marek Jaszczur ◽

Daniel Satoła ◽

Michał Karch

Keyword(s):

Air Flow ◽

Ventilation System ◽

Flow Characteristics ◽

Comfort Level ◽

Translational Velocity ◽

Comfort Zone ◽

Air Velocity ◽

Velocity Decay ◽

Different Diameters ◽

Comfort Criteria

The air diffuser is a very important component of any ventilation system, and the comfort level of ventilated space occupants depend among many other factors on properly designed and choice of diffusers. At present a large number of diffusers are produced to meet a different kind of requirements. One of the most efficient and very popular types of the diffuser is the vortex diffuser in which air flow has angular as well as translational velocity components. This paper investigates experimentally airflow characteristics of vortex ceiling diffuser and its effect on airflow in a ventilated space. Two thermal comfort criteria namely: mean age of the air and ventilation effectiveness have been used to predict the comfort zone inside the room. Effect of supply air velocity on the flow field is investigated and hence the on comfort and energy consumption. The results show that significant amount of energy can be saved by using vortex diffuser in reference to the other diffusers type. The values of the velocity decay coefficient were compared for different diameters of vortex diffuser.

Download Full-text

Air Terminal Devices Developed for Personal Ventilation Systems

Energies ◽

10.3390/en13071688 ◽

2020 ◽

Vol 13 (7) ◽

pp. 1688

Author(s):

Imre Csáky

Keyword(s):

Thermal Comfort ◽

Air Flow ◽

Ventilation System ◽

Air Velocity ◽

Head Region ◽

Personal Ventilation ◽

The University ◽

Velocity Turbulence ◽

Ventilation Systems

Using the personal ventilation systems may improve the thermal comfort sensation. At the University of Debrecen, a personal ventilation system was developed named ALTAIR. This paper presents the results of mean air velocity, turbulence grade, and draught measurements related to newly developed air terminal devices which are connected to the ALTAIR personal ventilation system. In order to define the measurement points it was essential to test the new air terminal devices (ATDs) in front of a black wall and smoke puffs. A series of measurements were carried out with isothermal air flow, mean air velocity, turbulence grade, and draught around the occupant head region in order to improve the thermal comfort sensation. Five different ATDs were analyzed.

Download Full-text