Design and fabrication of smart ceiling mop with adjustable head

The Ceiling cleaning process is one of the tedious tasks ever which involves removing algae, mold, lichen, dust, and moss from the surface. Cleaning of the roof becomes very difficult when the height of the roof is very high also an excess human effort is required which also makes the labor feel discomfort, in addition to muscle pain. By considering all the above-discussed difficulties, we have developed a concept of a semi-automatic ceiling cleaning machine that is capable of cleaning dirt, grime, algae, etc. on the ceiling. Enabling the machine in accessing hard-to-reach areas on the ceilingsand at higher altitudes. To make the controlling of the machine user-friendly an electric drive is incorporated, such that a person with less technical knowledge can access it with high accuracy. The power source for the entire operation is provided with the help of a battery which is internally installed in the setup. As an added advantage, the multi-head system is implanted, using this our setup can be used as a traditional brush head, and by changing the vacuum head, the setup is capable of performing dust collection operations using vacuum pressure. To make a machine which will take care of the safety of persons, save time and also shouldn't damage false ceiling structure. This method of ceiling cleaning can be used in hotels, offices, etc. which will give a more appealing look. This method is suitable for small, medium as well as large-scale applications.

The Optimal Performance of the Energy Efficiency of a Pulse Dust Collection System towards Sustainability

A growing number of manufacturers are realizing cost and environmental benefits through the sustainability of innovation and optimization processes. Based on polluting less and creating less, the study is pursuing sustainability on increasing operational efficiency by reducing costs and waste. Pulse dust collection systems are commonly used filtration equipment in industries and have lots of energy consumption due to running all day. This study is focused on the optimal parameters for energy saving and cost reduction, and the model is represented by the pressure drop of the filter and the residual powder. The characteristic values of the cleaning efficiency and the air permeability reduction are used for MATLAB to analyze the optimization state. This study found that the material of filter elements, the type of dust, the conditions of pulse-jet, and the filtering speed are the factors that affect the operational efficiency. In terms of cost, the pulse interval time in 10 s is the best parameter, and the pulse time does not affect the overall cost of the filter. Considering energy saving, 0.1 s of the pulse time is the best parameter. In addition, a lower dust concentration is a way to improve efficiency for increasing the filter life and reducing cost.

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

Control of Fine Cutting Chips to Improve the Processing Environment in CFRP Drilling

Carbon fiber reinforced plastic (CFRP) is increasingly used in aerospace, automobile, and other industries. With the improvement of carbon fiber reinforced thermoplastic molding technology using thermoplastic resin, it is expected that the applications of CFRP will be expand further. Because of the following issues, CFRP is known as a difficult-to-cut material. i) Machining CFRP is difficult. ii) Its finished surface deteriorates due to delamination and uncut fiber. iii) It has a shortened tool life due to severe tool wear. In addition to these issues, we has been problem presentation of fine cutting chips generated by machining. Because these fine cutting chips may scatter in the atmosphere and adversely affect the human body and machine tools, we have established a chip disposal technology that suppresses these issues to improve the processing environment. A previous study reported that shape of the tool edge is responsible in suppressing the generation of fine cutting chips. Here, we experimentally investigated the effects of tool edge shapes on the chip collection rate and tool life. An attempt was made to determine whether the same effect can be obtained by using the outside dust-collection method which is known that the dust collection efficiency is low. We revealed that the chip collection rate increases if a tool that suppresses the generation of fine cutting chips is used instead of a conventional tool; furthermore, the tool life is insensitive to coating. In contrast, a comparison of our results with previous findings indicates that the tool with a sharpened cutting edge has a longer tool life than the conventional twist drill with honing. A high cutting chip collection rate was obtained, even with the outside dust-collection method, which led to an improvement in the working environment.

About the mass of combustible dust deposited in the room

Темой данной статьи является рассмотрение расчетного метода оценки пыленакопления в помещении с оборудованием, содержащим дисперсные материалы, а задача заключается в его совершенствовании на основании современных представлений. Витающие в воздухе мелкие пылинки постепенно осаждаются на горизонтальных поверхностях, создавая угрозу внезапного перехода в состояние аэровзвеси и взрывообразного сгорания с образованием волны давления. Для определения категории помещения по взрывопожарной и пожарной опасности и разработки профилактических противопожарных мероприятий необходимо иметь математический инструмент, позволяющий оценивать количество пыли, которое может участвовать во взрыве. В статье предлагается определять критический диаметр частиц пыли, исходя из равенства скорости осаждения частиц и скорости распространения пламени. При этом скорость осаждения частиц следует определять по известному соотношению Стокса, а скорость распространения пламени принимать или по данным эксперимента, или среднестатистическую, равную 3 м/с. The dust that settles on the horizontal surfaces of equipment and building structures is inevitably contained in the premises in which technological process is carried out with the presence of combustible dispersed materials. The amount of dust deposited in a room can be determined in several ways. 1. Weighing the dust collected during cleaning. 2. Experimentally by placing dust collectors on different surfaces for a certain period of time. It should be considered the incompleteness of the previous dust collection, which depends on the dust collection method when determining the amount of dust deposited in the room. The amount of the remaining uncollected dust is estimated as 10 % of the detected dust if the cleaning was carried out by a mechanized method (dust extraction coefficient K = 0.9, and insufficient decontamination coefficient n = 0.1). The amount of remaining uncollected dust is estimated as 40% of the detected dust if cleaning was carried out manually using a dry method (dust extraction coefficient K = 0.6 and insufficient decontamination coefficient n = 0.4). The amount of remaining uncollected dust is estimated as 30% of the detected dust if the cleaning is carried out manually with a wet method (K coefficient = 0.7, and insufficient decontamination coefficient n = 0.3). Dust factor is the ratio of amount of dust suspended in the airspace to the total amount of dust in the room. It should be taken equal to 0.5, if the diameter of dust particles is more critical, and equal to 1, if the diameter of dust particles is less than the critical diameter. The diameter of the dust particles is critical, above which the dust ceases to spread the flame. The critical diameter can be determined based on the following considerations. Flame propagation through the air suspension will not occur if the particle deposition rate exceeds the flame propagation rate from bottom to top. The deposition rate is easily determined by the Stokes coefficient. The flame propagation rate can be determined experimentally or estimated as slightly higher than the average for most industrial dusts. The authors obtain a formula for calculating the critical diameter of dust particles equating the terminal velocity to flame propagation rate (3 m/s) and solving the Stokes equations of the particle diameter. The critical particle diameter of air suspension of combustible materials in most cases does not exceed 300 microns at flame propagation speed of 3 m/s. The obtained calculated values of the critical diameters are in satisfactory agreement with the literature data, and also confirm the correctness of the choice of dust formation coefficient K = 1 for dust with dispersion of less than 350 mkm. The air suspension ready for a secondary explosion is formed when combustible particulate material leaves the equipment as a result of an internal explosion. The aerosol with a high concentration of solid phase is formed in case of free precipitation from the device or from damaged packaging located above the floor level of the room. In this case, the amount of fuel capable for explosive combustion is determined by the amount of oxygen in the cloud, since the diffusion supply of oxygen from the outside does not have time to ensure complete combustion of the fuel. When the product spills unhindered, the resulting cloud has the shape of a volumetric cone with a base diameter equal to the height of the cone. It is possible to determine the amount of burned dust knowing the stoichiometric concentration of dust (%) required for its combustion per unit of air volume, as well as the volume of the dust cloud (V). The Pc value can be determined by the combustion reaction if the chemical composition of the dust is known. There are proposed refined equations for determining the critical diameter of combustible dust, the stoichiometric concentration during its combustion in a unit of air volume as well as the mass of dust deposited in the room. It is recommended to estimate the value of the stoichiometric concentration according to the combustion heat of dust for dusts of indeterminate chemical composition.

DEVELOPMENT AND RESEARCH OF A MACHINE FOR AIR CLEANING OF GRASS AND GRAIN SEEDS

To solve the problem of final cleaning of grain material from impurities, a pneumatic separator SP-2U-R has been developed, which allows the air flow to separate various weeds from the grain – straw impurities, weed seeds, dust, etc. To remove dust from the exhaust air, a rotary cross-flow dust collector is installed on the pneumatic separator. The novelty of the design and working process of the separator and dust collector is confirmed by patents RU No. 2165313 and No. 2122462, respectively. Theoretical studies of the working process of this dust collector are carried out. The conditions for the allocation of impurities from the dust-air flow: particle impurities with current polar coordinates r and j interacting with the rotor blade and moving through it, is considered to be isolated from the dust-air flow if the distance from the center of rotation will be r³R, and is achieved in the angular sector φ=φвых£φmax, where φвых=φо+ω·tвых, and Smax the largest distance traveled by a particle to the center of the rotor does not exceed the length of rotor blades: Smax £ l. The mathematical model of the trajectory of the particles of impurities relative to the rotor blades of a dust collector depending on its parameters: Dн - outer diameter, l - length of the blade, z - number of rotor blades, φо - the angle of the beginning of interaction of the impurity with a shovel, f - coefficient of friction of the particles on the blades, kп - coefficient of sail particles of impurities, V - speed dusty flow, n - frequency of rotation of the rotor, – it allows to evaluate the efficiency of dust collection at the early stages of research, as well as to develop design documentation for a device with pre-known operational characteristics