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Balanced and sustainable development has challenges in utilizing the best efficiency technologies, using new types of materials with reduced environmental impact, including composite types, reusable materials, and easily recyclable consumer adaptable products. One understudied biologically produced material is mycelium, the scientifically studied and improved cultivation of which produces an environmentally friendly material with unique properties with a wide range of applications. In this work, filtration fillers from mycelia of different cultivation periods and their abilities to filter airflow from solid particles were experimentally studied. Numerical modeling studied the interaction and trapping of particles in the flow with the surface of mycelium filters. The results of the research revealed a high airflow filtration efficiency of more than 91%, as well as differences and advantages in the properties and structure of mycelia of different growth periods, and the need for further study of this biomaterial. [ABSTRACT FROM AUTHOR]

The main aim of this investigation was an experimental analysis of the air cleaning efficiency in a mock-up next-generation air cleaning device - one-level 8-channel industrial cyclone-separator with quarter-rings - while changing parameters of the inner structure and the assessment of the effects of dispersion of particulate matter. Therefore, the research was carried out in two stages: the first stage covered the analysis of the efficiency of the multi-channel cyclone with particulate matter of

Research into gas flow motion as a transported phase and pollutant - particulate matter (PM) is of crucial importance, their changes in particular areas of the object require knowledge of improving the apparatus. A cyclone is considered one of the most popular devices due to the new modified multi-channel design that involves combined separation and filtration phenomena. The findings of an accurate numerical model provide an opportunity to verify long-term experimental studies. In addition, it is possible to determine the impact of the designed principal elements of the structure comprising secondary gas inlets, inner slits and the convex bottom on gas and PM motion through verification conducting experimental research. The study focuses on simulating the upgraded cyclone using the SST k-omega model. The research has been conducted under the specified gas flow conditions such as high temperature and relative humidity (aggressive) gas and presents the results of the physical model to compare with. To achieve greater computational accuracy, a digital model of the cyclone made of specific volumetric elements has been developed thus expanding the grid and stepping to form the boundary zone. As a result, numerical simulation results differ by no more than 12.8% compared to the experimental studies results. [ABSTRACT FROM AUTHOR]

Special cyclone - gas treatment device which can be applied to remove the fine particulate matter bigger than 2 micrometres from aggressive gas flow at a temperature of 50-145 °C and a relative humidity of more than 95% and can be achieved the cleaning efficiency over 90%. Cyclone work is based on centrifugal forces and the resulting additional filtration process operation. Cyclone structure equipped with primary and secondary gas flow inflows through which gas dispersed flow is supplied parallel to all channels of the cyclone. Analysed modified multi-channel cyclone can be effectively treated from fine particulate matter, during the cleaning of aggressive gas flow an adhesion/cohesion phenomena could be reduced. Research of aerodynamic parameters it's the first step of studies to determine the optimal case, at the average gas flow velocity in cyclone channels were 8, 12 and 16 m/s, the gas flow dynamics dependencies into cyclone were determined. [ABSTRACT FROM AUTHOR]

Contaminated gas cleaning from finely divided solids is carried out using a new generation of multi-channel design cyclones. The application of these devices are separated and precipitated particles with a minimum diameter up to 2 micrometers, reaching up to 95% cleaning efficiency. Cyclones of such constructions are usually used under usual conditions at elevated temperature and low humidity. Under aggressive conditions, these devices can be clogged, and their recovery is not possible. Further studies are research into the application of constructive solutions to adapt the cyclone gas cleaning of the particulate matter under aggressive conditions. This theoretical evaluation has described the characteristics change of gas flow and particulate matters at different aggressive environment. Such conditions were loudly describe the gas-flow high-temperature range of 50-200 °C and gas-vapor stream, the humidity reaches 70-100%. Estimated aggressive conditions on the gas flow dynamics forces - pressure, resistance and centrifugal, and particulate mechanical - gravitational and adhesion strength. All parameters are evaluated in comparison with the values under normal conditions. [ABSTRACT FROM AUTHOR]

Multi-level multi-channel cyclone - the lately designed air cleaning device that can remove ultra-fine 20 μm particulate matter (PM) from dusted air and reach over 95% of the overall cleaning efficiency. Multi-channel cyclone technology is based on centrifugal forces and has the resulting additional filtering process operation. Multi-level structure of cyclone allows to achieve higher air flow cleaning capacity at the same dimensions of the device, thus saving installation space required for the job, production and operating costs. Studies have examined the air flow parameters change in one–, two– and three–levels multichannel cyclone. These constructions differ according to the productivity of cleaned air under the constant peripheral and transitional (50/50 case) air flow relations. Accordance with the results of air flow dynamics - velocity distribution of multi-channel cyclone, aerodynamic resistance and efficiency can be judged on the flow turbulence, the flow channel cross-section and select the most appropriate application. Cleaning efficiency studies were carried out using fine granite and wood ashes PM. The maximum cleaning efficiency was 93.3%, at an average of 4.5 g/m3, the aerodynamic resistance was equal to 1525 Pa. [ABSTRACT FROM AUTHOR]

The conducted research has proved the dependence of gas flow rate in the separate channels of the two-level multichannel cyclone at a different inflow velocity and the number of channels. The carried out investigation demonstrates the dependence of changes in velocity in the channels under varying relations between peripheral and transitional flows. The work of a cyclone of the channel is based on centrifugal forces and an additionally occurring filtration process caused by the interaction between the flow coming from the later channel (peripheral) and the other floating towards the axis of the cyclone (transitional). The structure of the two-level cyclone allows reaching higher gas (air) flow efficiency performing similar measurements of the applied equipment. New cyclones are designed upon the establishment of the tangential airflow and using the aerodynamic characteristics of the cyclones that have better efficiency than the ordinary ones. The aim of this research is to investigate changes in airflow rate at different levels of the cylindrical casing and their channels by regulating the half-rings of the multichannel cyclone, and changing relations of peripheral and transitional flows that get into the channels when the speed of the inflow/capacity of the cyclone varies. The maximum aerodynamic resistance is 1562 Pa when flow distribution ratio is 50/50 and inflow velocity is 15.3 m/s. According to the obtained experimental data, the effectiveness of cleaning the air flow polluted with the solid particles of more than 20 microns in diameter is up to 93% when the concentration of such particles in the airflow before cleaning is 5.9 g/m³. [ABSTRACT FROM AUTHOR]

The article deals with a problem of experimental investigation and numerical simulation of gas aerodynamics of a multi-channel spiral cyclone with a tangential inlet. The paper presents an overview of experimental and theoretical works on the cyclones having a particularly complex turbulent flow and focuses on three-dimensional transport differential equations for a non-compressible laminar and turbulent flow inside the cyclone. The equations have been solved applying the numerical finite volume method using the RNG (Re-Normalisation Group) k-ε turbulence model. The numerical simulation of the flow cyclone has been carried out. The height of the cyclone is 0.80 m with 0.33 m in diameter, the height of the spiral-cylindrical part -0.098 meters and that of the cone - 0.45 m. Inlet dimensions (cylindrical part on the side), in accordance with drawings makes axb = 28x95 mm. The mathematical model for the air traffic movement cyclone has accounted for Navier-Stokes (Reynolds) three-dimensional differential equations. The simulation results have been obtained with reference to the cyclone of tangential velocity profiles using RNG k-ε turbulence model. The inlet velocity of 5.1 m/s slightly differs from experimental results, thus making an error of 7%. [ABSTRACT FROM AUTHOR]

The conducted investigation is aimed at providing information on air flow parameters in the cylindrical and spiral shell (de-vices are designed for separating solid particles from air flow having tangent flow inlet). Experimental research has employed multi-cyclones created by the Department of Environmental Protection at Vilnius Gediminas Technical University. The study is focused on investigating and comparing the distribution of the dynamic pressure of the airflow in six-channel cyclones inside the structures of devices. The paper establishes and estimates the efficiency of air cleaning changing air phase parameters using different particulate matters. The efficiency of the cyclone has been defined applying the weighted method based on LAND 28-98/M-08 methodology. The article presents the results of experimental research on the air cleaning efficiency of cylindrical and spiral shells using 20 µm glass and clay particulate matter under the initial concentration that may vary from 500 mg/m³ to 15 g/m³ using semi-rings with windows at different positions. The obtained results has shown that the maximum efficiency of the cylindrical shell increases up to 87,3 % while the initial concentration of glass makes 15 g/m³. [ABSTRACT FROM AUTHOR]