Simulation of dust-air flow near a rotating disk cylinder suction unit

2019 ◽  
pp. 70-74
Author(s):  
A. B. Goltsov ◽  
K. I. Logachev ◽  
O. A. Averkova ◽  
V. A. Tkachenko
Keyword(s):  
Computer Model ◽  
Lateral Surface ◽  
Cylindrical Surface ◽  
Air Flow ◽  
Rotating Disk ◽  
Rotating Cylinder ◽  
Dust Removal ◽  
Dust Particles ◽  
Operating Parameters

A dust-air flow near a vertically located rotating cylinder with a suction unit located on the lateral surface was investigated. A computer model of this suction unit was developed, the effect of disks mounted on a cylindrical surface on the intake air flow and on the capture of dust particles in the suction unit, as well as the design and operating parameters of the proposed disk cylindrical suction (DCC), which reduce the dust loss. The influence of the size and number of discs, aspiration air flow on dust removal has been established. This design of a rotating disk cylinder suction unit can be used in aspiration shelters with the function of a dust-collecting chamber. Ill. 6. Ref. 15.

NUMERICAL SIMULATION OF AIR DUST FLOW IN A DUST COLLECTING NOZZLE WHEN DRILLING FLAT SURFACES

2021 ◽  
pp. 37-48
Author(s):  
Олег Викторович Тирон ◽  
Иван Николаевич Логачев ◽  
Константин Иванович Логачев
Keyword(s):  
Numerical Simulation ◽  
Computer Model ◽  
Air Flow ◽  
Dust Emission ◽  
Flow Simulation ◽  
Angular Speed ◽  
Dust Particles ◽  
Maximum Diameter ◽  
Dust Collection ◽  
Flat Surfaces

В процессе сверления стеновых конструкций электродрелями возникают значительные пылевыделения, негативно влияющие на здоровье человека и загрязняющие окружающее пространство. Актуальным является разработка компактных насадков-пылеуловителей, снижающих пылевыделения. Предложена конструкция пылеулавливающего насадка - отсоса для локализации пылевыделений при сверлении электродрелями плоских поверхностей. Для выбора необходимого расхода отсасываемого из насадка воздуха и наиболее рациональных его размеров разработана компьютерная модель движения пылевоздушного потока с учетом влияния вращения сверла. Использовался программный комплекс SolidWorks с расширением Flow Simulation, где численно решались уравнения Навье-Стокса и неразрывности, замкнутые при помощи k - ε модели турбулентности. Динамика пылевых частиц определялась численным решением дифференциального уравнения их движения с коэффициентом сопротивления Хендерсона. Для проверки адекватности и достоверности модели проведены экспериментальные замеры скорости воздушного потока, увлекаемого вращающимся сверлом. При помощи обработки полученных экспериментальных и расчетных значений скорости по статическим критериям оценены достоверность, адекватность модели, воспроизводимость экспериментов, теснота связи. В качестве критерия эффективности улавливания пыли насадком, используется величина максимального диаметра улавливаемых пылевых частиц. Выявлены закономерности изменения величины максимального диаметра от угловой скорости вращения сверла, изменении радиуса всасывающего отверстия и его удаленности от края насадка. В результате численного моделирования показано, что если не учитывать количество воздуха, увлекаемого вращающимся сверлом, то возможны значительные погрешности при определении максимального диаметра уловленных частиц. Разработанная компьютерная модель и выявленные закономерности улавливания пылевых частиц могут быть использованы для создания эффективного пылеулавливающего насадка. In the process of drilling wall structures with electric drills, significant dust emissions occur, which negatively affect human health and pollute the surrounding space. Development of compact nozzles-dust collectors that reduce dust emission is urgent. We offer a new design of a dust-collecting nozzle - suction for the localization of dust when drilling flat surfaces with electric drills. To select the required flow rate of air sucked out of the nozzle and its most rational dimensions, a computer model of the movement of the dust-air flow has been developed, taking into account the influence of the rotation of the drill. We used the software package SolidWorks , in the Flow Simulation extension where the Navier-Stokes and continuity equations were numerically solved using the k - ε turbulence model. The dynamics of dust particles was determined by numerically solving the differential equation of their motion with the Henderson drag coefficient. We carried out a number of experimental measurements of the speed of the air flow activated by the rotating drill to check the adequacy and reliability of the model. By processing the obtained experimental and calculated values of the velocity according to static criteria we assessed the reliability, adequacy of the model, reproducibility of experiments and tightness of the connection. As a criterion for the efficiency of dust collection by the nozzle, the value of the maximum diameter of the captured dust particles is used. As well we revealed some regularities of the change in the value of the maximum diameter from the angular speed of rotation of the drill, the change in the radius of the suction hole and its distance from the edge of the nozzle. As a result of numerical simulation, it is shown that not taking into account the air flow created by the rotating drill leads to significant errors, reaching 68%. The developed computer model and the revealed patterns of trapping dust particles can be used to create an effective dust-collecting nozzle.

Numerical simulation of the dynamics of dust in a rotary dust collector with an adjustable air flow

2021 ◽  
pp. 70-75
Author(s):  
V. V. Koochetov ◽  
A. B. Gol’tsov ◽  
K. I. Logachev ◽  
O. A. Averkova ◽  
V. M. Kireev
Keyword(s):  
Numerical Simulation ◽  
Rational Design ◽  
Air Flow ◽  
Dust Particles ◽  
Operating Parameters ◽  
Dust Collector ◽  
Centrifugal Separator ◽  
Flow Regulator

A rotary dust collector has been developed that works on the principle of a centrifugal separator. A feature of its design is the presence of a bypass recirculation channel of cleaned air with a flow regulator, two outlet pipes with flow uncoilers in the form of spiral channels. The calculation of the motion of dust particles with a density of 3000 kg/m3 and a diameter of 1 to 100 microns has been performed. Research has been carried out to improve the efficiency of the apparatus using a central compositional plan and to establish rational design and operating parameters of the mixer for recirculating and purified air.

scholarly journals Spatial distributions of airborne dust in a cows barn exposed to influence of different ventilation rates

2013 ◽  
Vol 29 (2) ◽  
pp. 373-383
Author(s):  
G. Topisirovic ◽  
D.V. Petrovic ◽  
R. Maletic
Keyword(s):  
Flow Rate ◽  
Indoor Air ◽  
Rotation Rate ◽  
Natural Ventilation ◽  
Electronic Control Unit ◽  
Air Flow ◽  
Control Unit ◽  
Dust Particles ◽  
Airborne Dust ◽  
Stability And Instability

Information on the concentration of dust particles is an important microclimate parameter that characterizes the local environmental quality of each livestock building. Increased concentration of dust particles primarily affects the indoor air quality and, consequently, the animal and workers health. Among many others, ventilation rate is a vital parameter that controls the spatial distribution of airborne dust particles in livestock buildings. This was the main motive for authors of this paper to research the influence of rotation rate of under-roof axial fans (i.e. the air flow rate) on airborne dust particles distribution crossover the barn specified for tied cows breeding. During a series of performed experiments, six different air flow rates have been maintained in the range between 0 m3?h-1 and 48000 m3?h-1. Flow rate has been controlled by special electronic control unit, which provided six different rotation rates of two under-roof fans, including the neutral regime (natural ventilation only). Measurements have been performed at four typical height levels (0,5 m; 1,0 m; 1,5 m and 2,0 m), cross-over the three lateral and four longitudinal characteristic building sections. Consequently, 48 measuring points were appropriately selected, in order to cover the indoor space in adequate way. Comparative analysis of air flow velocities and dust concentrations showed that this fan setup may give satisfactory results under adequate operational regime. Certain working regimes were recommended for use, and the third rotation rate step, generating the airflow of 37300 m3?h-1 or indoor air exchange level of approximately 25 h-1, has been found as the most suitable. Projekat Ministarstva nauke Republike Srbije, br. TR31086: Optimization of technological procedures and zoo-technical resources on farmsin purpose of milk production sustainability improvement, br. TR 31051: Improvement of biotechnological procedures as a function of rational utilizationof energy, agricultural products productivity and quality increase, br. III46009: Improvement and development new technological procedures in production ofanimal products, to achieve high quality and safe competitive products inmarket i br. OI 174011: Dynamical stability and instability of mechanical systems exposed to stochasticdisturbances

Mathematical Modeling of the Process of Operation of the Drying Chamber of a Tower Grain Dryer With a Suction Air Flow

2020 ◽  
pp. 114-121
Author(s):  
Viktor Shvidia ◽  
◽  
Serhii Stepanenko ◽  
Keyword(s):  
Moisture Content ◽  
Air Flow ◽  
Initial Moisture Content ◽  
Material Balance ◽  
Operating Parameters ◽  
Conservation Of Energy ◽  
Grain Moisture ◽  
Optimal Mode ◽  
Drying Chamber ◽  
Main Operating

In the article, a drying scheme in a tower grain dryer has been developed, equations for the conservation of energy and material balance for grain, equations for mass transfer and heat transfer between the drying agent and grain have been drawn up. On their basis, analytical dependences of changes in the temperature and moisture content of grain, moisture content and temperature of the drying agent along and in the width of the drying channel were obtained, depending on the operating parameters (the value of rarefaction in the drying channel, the speed of grain movement along the drying channel, the speed of movement of the drying agent, the initial temperatures of the grain and drying agent, initial moisture content of grain, as well as initial moisture content of drying agent). Their analysis facilitates the work in choosing the optimal mode. The developed analytical dependences of changes in the main drying parameters (moisture and temperature of grain, moisture content and temperature of the drying agent) along the length and width of the drying channel in tower dryers with suction air flow make it possible to link the main operating parameters, which facilitate the choice of rational drying modes.

Numerical and Experimental Study of Flow and Convective Heat Transfer on a Rotor of a Discoidal Machine with Eccentric Impinging Jet

2019 ◽  
pp. 1-29
Author(s):  
Chadia Haidar ◽  
Rachid Boutarfa ◽  
Mohamed Sennoune ◽  
Souad Harmand
Keyword(s):  
Heat Transfer ◽  
Experimental Study ◽  
Steady State ◽  
Convective Heat Transfer ◽  
Convective Heat ◽  
Air Flow ◽  
Impinging Jet ◽  
Rotating Disk ◽  
Reynolds Numbers ◽  
Air Jet

This work focuses on the numerical and experimental study of convective heat transfer in a rotor of a discoidal the machine with an eccentric impinging jet. Convective heat transfers are determined experimentally in steady state on the surface of a single rotating disk. The experimental technique is based on the use of infrared thermography to access surface temperature measurement, and on the numerical resolution of the energy equation in steady-state, to evaluate local convective coefficients. The results from the numerical simulation are compared with heat transfer experiments for rotational Reynolds numbers between 2.38×105 and 5.44×105 and for the jet's Reynolds numbers ranging from 16.5×103 to 49.6 ×103. A good agreement between the two approaches was obtained in the case of a single rotating disk, which confirms us in the choice of our numerical model. On the other hand, a numerical study of the flow and convective heat transfer in the case of an unconfined rotor-stator system with an eccentric air jet impinging and for a dimensionless spacing G=0.02, was carried out. The results obtained revealed the presence of different heat transfer zones dominated either by rotation only, by the air flow only or by the dynamics of the rotation flow superimposed on that of the air flow. Critical radii on the rotor surface have been identified

Optimization of Lift Generation for a Spinning Surface through its Design and Speed

2015 ◽  
Vol 793 ◽  
pp. 630-634
Author(s):  
Azharrudin Asrokin ◽  
Mohammad Rizal Ramly
Keyword(s):  
Rotational Motion ◽  
Cylindrical Surface ◽  
Lift Force ◽  
Rotating Cylinder ◽  
Golf Ball ◽  
Tennis Ball ◽  
Straight Path ◽  
Soccer Ball ◽  
The One

The rotational motion of a ball, be it a tennis ball, a golf ball or even a soccer ball, will yield a curving trajectory during airborne. We would best describe this phenomenon by its popular handle, the curve ball. The vortex generated by the ball is the one responsible for such behavior. Basically, the stronger the vortex, the more enhanced the arched flight we will get. Simply put, the ball is producing lift, thus the inclination to deviate to one side from otherwise a straight path. The same principle was employed to harness lift force in rotating cylinder. The question is, how strong the vortex should be and how much is too much. In this paper, we found that certain shape and speed (to make the surface rougher and yield stronger vortex) of the cylindrical surface will determine whether or not it generates better lift when the surface is rotating.

Optical Modeling of Reflectivity Loss Caused by Dust Deposition on CSP Mirrors and Restoration of Energy Yield by Electrodynamic Dust Removal

2014 ◽  
Author(s):  
Jeremy Stark ◽  
Julius Yellowhair ◽  
John N. Hudelson ◽  
Mark Horenstein ◽  
Malay Mazumder
Keyword(s):  
Power Plants ◽  
Specular Reflection ◽  
Mie Scattering ◽  
Dust Removal ◽  
Dust Particles ◽  
Energy Yield ◽  
Dust Deposition ◽  
Optical Modeling ◽  
Specular Reflectivity ◽  
Semi Arid

For large scale CSP power plants, vast areas of land are needed in deserts and semi-arid climates where uninterrupted solar irradiance is most abundant. These power facilities use large arrays of mirrors to reflect and concentrate sunlight onto collectors, however, dust deposition on the optical surfaces causes obscuration of sunlight, resulting in large energy-yield losses in solar plants. This problem is compounded by the lack of natural clean water resources for conventional cleaning of solar mirrors, often with reflective surface areas of large installations exceeding a million square meters. To investigate the application of transparent electrodynamic screens (EDS) for efficient and cost effective dust removal from solar mirrors, both optical modeling and experimental verifications were performed. Prototype EDS-integrated mirrors were constructed by depositing a set of parallel transparent electrodes into the sun-facing surface of solar mirrors and coating electrodes with thin transparent dielectric film. Activation of the electrodes with a three-phase voltage creates an electrodynamic field that charges and repels dust electrostatically by Coulomb force and sweeps away particles by a traveling electrodynamic wave. We report here brief discussions on (1) rate of deposition and the properties of dust with respect to their size distribution and chemical composition in semi-arid areas of the southwest US and Mojave Desert and their adhesion to solar mirrors, (2) optical models of: (a) specular reflection losses caused by scattering and absorption by dust particles deposited on the surface based on Mie scattering theory, and (b) reflection loss by the integration of EDS on the mirror surface, computed by FRED ray-tracing model. The objective is to maintain specular reflectivity of 90% or higher by frequent removal of dust by EDS. Our studies show that the incorporation of transparent EDS would cause an initial loss of 3% but would be able to maintain specular reflectivity more than 90% to meet the industrial requirement for CSP plants. Specular reflection measurements taken inside a climate controlled environmental chamber show that EDS integration can restore specular reflectivity and would be able to prevent major degradation of the optical surface caused by the deposition of dust.

Sign in / Sign up

Export Citation Format

Share Document