IMPROVING THE DESIGN OF THE CHAMBER SEED MORDANT

2020 ◽  
Vol 36 (2) ◽  
pp. 75-85
Author(s):  
R.Z. Aкhunov ◽  
Keyword(s):  
Air Flow ◽  
Suspension Flow ◽  
Work Safety ◽  
Axial Fan ◽  
Excessive Pressure ◽  
Air Circulation

The article presents the modernization of the design of the universal seed mordant PSS-20 by installing an axial fan and air ducts for closed air circulation in the processing chamber, which will ensure the full use of the mordant, work safety and increase the productivity of cultivated crops. The main advantage of this design is that the seeds in the same plane as the suspension flow is affected by the air flow, which improves the penetration into the layer. Air ducts make it possible to reuse the suspension that has not settled on the seeds. This is achieved due to the closed lid design. During operation, the fan creates excessive pressure inside the seed stream and rarefaction outside, and so small drops of solution that have penetrated the seed stream are sucked in by the fan and re-fed into the stream.

scholarly journals The air-flow structure and gas dispersion behavior in gas tunnel construction through bench cut method

2019 ◽  
Vol 23 (3 Part A) ◽  
pp. 1417-1424
Author(s):  
Rong Liu ◽  
Song Ren ◽  
Jinyang Fan ◽  
Fei Wu ◽  
Ngaha William
Keyword(s):  
Flow Structure ◽  
Air Flow ◽  
Gas Diffusion ◽  
Circulation Zone ◽  
Gas Dispersion ◽  
Diffusion Characteristics ◽  
Tunnel Section ◽  
Cut Method ◽  
Field Workers ◽  
Air Circulation

The inability to accurately predict the in rush of gas increases the fear of field workers security and unnecessary investments in tunnel ventilation. In this study, a 3-D numerical model was established to investigate the air-flow structure and gas diffusion characteristics of a gas tunnel during construction. The result showed that the flow inside the bottom bench mainly came from the re-circulation zone of the upper bench. Mutation in the tunnel section due to bottom bench excavation would cause the formation of some air circulation in the bottom bench. The circulation air in the bottom bench came from the re-circulation zone of the upper bench, while the air-flow in the considered zone was a polluted air. Based on the obtained results, there was no accumulation of CH4 inside the bottom bench. Nevertheless, gas gushing will still appear during the construction of the bottom bench surface, which can possibly lead to gas disaster. This study aims to provide some guidance for tunnel engineers on safety monitoring systems.

scholarly journals The use of the interaction of convex wall jets for ventilation with variable air flow

2021 ◽  
Vol 37 ◽  
pp. 7-12
Author(s):  
V.  Korbut ◽  
V. Mileikovskyi ◽  
V. Dziubenko ◽  
I.  Sachenko
Keyword(s):  
Air Flow ◽  
Branch Pipe ◽  
Geometrical Shape ◽  
Wall Jets ◽  
Cross Sectional ◽  
Working Zone ◽  
Gravitational Forces ◽  
Convex Wall ◽  
Air Circulation ◽  
Air Exchange

The most energy efficient ventilation and air-conditioning is variable air flow (VAV) depending on the needs of a room. To avoid broken air circulation by gravitational forces, the most of air diffusers should change geometrical shape and sizes using additionall automation of them. In contrast, high stability of a scheme of air exchange organization with air supply over a working zone by convex wall jets that interact with each other under conditions of variable air flow, is confirmed. This scheme is useful in cases where it is impossible to supply air directly to the working zone. Simulation of the air exchange organization in an exhibition hall of International Exhibition Centre in Kyiv with ventilation at a variable air volume (VAV) in the entire possible range of performance control has been performed. The floor area is 5258 m2, the height is 19 m. The outdoor air-flow at design conditions (100 % load) is 21.667 m3/s (78000 m3/h). The minimum load corresponds to the absence of solar radiation and only some people in the room. The minimum air-flow is 25 % of the design one. The proposal air scheme is single-zonal using 24 diffusers PES-D-8-10/15-0,9 4 m above the floor and air removal from the upper zone. The air distributor have a diameter of a cylindrical surface and an inlet branch pipe of 8 dm (800 mm). There are 10 rows of nozzles at an angle π/12 (15 °) to the horizon on each distributor. The total area of the air outlet on them is equal to 0.9 of the cross-sectional area of the inlet pipes. Due to forces of the vacuum holding of jets on the wall surfaces, the influence of gravitational forces is significantly reduced. This avoids the automation of air distribution devices to stabilize the scheme of air circulation in the room by gravitational forces. It is enough to install valves with actuators on branches of a network of air ducts. Thus, the economic benefit of the system is confirmed both at the stage of installing and during operation.

Evaluation of the Influence of One Air Circulation System on LGS House Indoor Thermal Environment

2012 ◽  
Vol 204-208 ◽  
pp. 4343-4348 ◽  
Author(s):  
Jing Li ◽  
Zhi Qiang Deng ◽  
Chuan Li ◽  
Di Zhou
Keyword(s):  
Flow Velocity ◽  
Influence Factor ◽  
Thermal Environment ◽  
Air Flow ◽  
Green Energy ◽  
Comfort Level ◽  
Circulation System ◽  
Indoor Thermal Environment ◽  
Air Flow Velocity ◽  
Air Circulation

Basing on 3 dimensional simulation of Airpak software, it studied the indoor thermal environment characteristics and influence factor of LGS house which provided with one air circulation system. It investigated the indoor air flow velocity field, temperature field, air age distribution and PMV-PPD distribution, and completed prediction and evaluation for air flow organization and air quality. The study shows that this air circulation system improves the air flow velocity and temperature distribution of LGS house indoor, provided a good thermal environment and air exchanging effect for indoor with low energy consumption, this has a significant meaning for improving comfort level of LGS house on the basis of meeting green energy saving.

Control of Bacterial Pathogens during Processing of Cold-Smoked and Dried Salmon Strips

2004 ◽  
Vol 67 (2) ◽  
pp. 347-351 ◽  
Author(s):  
M. W. EKLUND ◽  
M. E. PETERSON ◽  
F. T. POYSKY ◽  
R. N. PARANJPYE ◽  
G. A. PELROY
Keyword(s):  
Staphylococcus Aureus ◽  
Listeria Monocytogenes ◽  
Water Activity ◽  
Bacterial Pathogens ◽  
Air Flow ◽  
Water Phase ◽  
Laboratory Studies ◽  
Pellicle Formation ◽  
Chemical Changes ◽  
Air Circulation

Microbiological and chemical changes were determined during the smoking and drying of salmon strips processed at 29 to 31°C for 4 days at a facility in Alaska in 1993. During the process, Staphylococcus aureus populations increased to more than 105 CFU/g after 2 to 3 days of processing. Subsequent laboratory studies showed that a pellicle (dried skinlike surface) formed rapidly on the strips when there was rapid air circulation in the smokehouse and that bacteria embedded in or under the pellicle were able to grow even when heavy smoke deposition occurred. Under these conditions, an inoculum of 26 CFU/g of S. aureus increased to 105 CFU/g after 3 days of processing. Elimination of preprocess drying and reduction in air flow during smoking resulted in smoke deposition before pellicle formation and enabled the product to reach levels of water-phase salt and water activity that inhibit the growth of S. aureus and Listeria monocytogenes. In 1994, these modifications were then applied during processing at an Alaskan facility, and S. aureus could not be detected in the finished product. L. monocytogenes was detected in the raw product area, on the processing tables, and on the raw salmon strips, but it was not detected in the finished product when the smoke was applied before pellicle formation.

Effects of Sand Ingestion Through an Axial Fan With Blade Staggering

2008 ◽  
Author(s):  
Adel Ghenaiet
Keyword(s):  
High Speed ◽  
Air Flow ◽  
Operating Conditions ◽  
Sand Particle ◽  
Computational Domain ◽  
Axial Fan ◽  
Complex Flow ◽  
Particle Trajectories ◽  
Flow Rates ◽  
The Impact

This paper presents the numerical results of sand particle trajectories and erosion patterns in a single stage axial fan used in industrial air ventilation, and the subsequent deterioration of the blade geometry. Attention is focused in particular on the effects of rotor blade staggering and the operating flow rates. By adopting the Lagrangian formulation to study the dynamics of particulate air-flow, the flow-field within the blade passage is solved separately. Particle trajectories computation is based on a stochastic tracking algorithm, which includes eddy-lifetime concept for turbulence, and accounts for the complex flow patterns near walls, random particle rebound factors, in addition to particle size, shape and fragmentation. The equations of motion are solved in a stepwise manner, whereas, particle tracking in different cells of the computational domain is based on the finite element method. The computation of the particle trajectories yields the impact locations along the blade surfaces, where the corresponding erosion patterns are calculated by using experimental correlations. The results of the numerical simulations carried out at low and high concentrations of MIL-E5007E sand particles, for different fan blade staggering and mass flow rates, revealed that the main impacted areas are found along the blade leading edge, over a strip of the blade suction side and a large area of the pressure side, in addition to the tip and casing, but with rare impacts on the hub. The rates of erosion in this axial fan are found to depend strongly on the air flow condition and the blade staggering. In all operating conditions of this axial fan, the rates of erosion are lower in comparison to high speed fans and compressors. Erosion analysis could be used in aerodynamic and mechanical design procedures to produce turbomachinery blading that would be less susceptible to erosion.

Investigation of Temperature and Air Flow inside Para Rubber Greenhouse Solar Dryer Incline Roof Type by Using CFD Technique

2014 ◽  
Vol 931-932 ◽  
pp. 1238-1242 ◽  
Author(s):  
Praphanpong Somsila ◽  
Umphisak Teeboonma
Keyword(s):  
Fluid Dynamics ◽  
Computational Fluid Dynamics ◽  
Air Flow ◽  
Solar Dryer ◽  
Solar Greenhouse ◽  
Product Surface ◽  
Air Circulation ◽  
Dynamics Method

Para rubber solar greenhouse dryer is a one method of drying and it can be responded to requirement of agriculturist on amount of drying product. Present, the dryer was being built many type for made drying agriculture product. The air circulation and temperature scatter havent been used for the dryer built process, which are cause of fungus on product surface and product dehydrate not all over. Therefore, the objective of this research is to study temperature distributes and air circulations inside Para rubber solar greenhouse dryer of incline roof type using computational fluid dynamics method. The result showed that temperature and velocity of air were good distributing all area and havent air cluster under the roof.

scholarly journals Minimization of Temperature Ranges between the Top and Bottom of an Air Flow Controlling Device through Hybrid Control in a Plant Factory

2014 ◽  
Vol 2014 ◽  
pp. 1-7 ◽  
Author(s):  
Seung-Mi Moon ◽  
Sook-Youn Kwon ◽  
Jae-Hyun Lim
Keyword(s):  
Hybrid Control ◽  
Air Flow ◽  
Air Distribution ◽  
Efficient Operation ◽  
Growth Environment ◽  
Closed Type ◽  
Plant Factory ◽  
Temperature Ranges ◽  
The Difference ◽  
Air Circulation

To maintain the production timing, productivity, and product quality of plant factories, it is necessary to keep the growth environment uniform. A vertical multistage type of plant factory involves different levels of growing trays, which results in the problem of difference in temperature among vertically different locations. To address it, it is necessary to install air flow devices such as air flow fan and cooling/heating device at the proper locations in order to facilitate air circulation in the facility as well as develop a controlling technology for efficient operation. Accordingly, this study compares the temperature and air distribution within the space of a vertical multistage closed-type plant factory by controlling cooling/heating devices and air flow fans harmoniously by means of the specially designed testbed. The experiment results indicate that in the hybrid control of cooling and heating devices and air flow fans, the difference in temperature decreased by as much as 78.9% compared to that when only cooling and heating devices were operated; the air distribution was improved by as much as 63.4%.

scholarly journals KAJIAN KENYAMANAN RUANG KULIAH TN II JURUSAN TEKNIK FISIKA UNIVERSITAS GADJAH MADA (UGM) DITINJAU DARI ASPEK TERMAL DAN POLA ALIRAN UDARA MENGGUNAKAN FLUENT

2016 ◽  
Vol 2 (2) ◽  
Author(s):  
Sunanto Sunanto ◽  
Karsid Karsid
Keyword(s):  
Temperature Distribution ◽  
Temperature Variation ◽  
Air Temperature ◽  
Geometric Modeling ◽  
Air Flow ◽  
Model Testing ◽  
Velocity Variation ◽  
Air Velocity ◽  
Free Air ◽  
Air Circulation

Temperature and air circulation is an important factor in a building since it is closely related to health comfort. Therefore, the design of a building should be carry out precisely in getting a clean, healthy and comfortable air circulation in accordance to the requirement of the room.In order to carried out a good building designing, a research was needed to understand temperature distribution, the pattern of air flow and its velocity. In this research, a Classroom of TN II JTF UGM. This classroom have 1030 cm length, 790 cm of width, and 330 cm of height. The size of the windows is 100 x 100 cm and place 1m from the floor. The size of the doors is 140 x 210 cm. The windows are assumed to be widely open, the door always opened. The researched begins with geometric modeling of the model by using Gambit 2.2.30 and continued with model testing using Fluent 6.2.16. The test is carried out by giving three velocity variation of free air flowing i.e.: from 1.3 m/s, 3.61 m/s and 5.92 m/s, two direction variation of open air flowing and two variation temperature of free air i.e.: 21.50C and 27.650C.The standard of comfortable air velocity used in the room is 0.15 < V < 0.25 m/s, The standard of comfortable temperature used in the room is 20.50C and 27.10C. The air velocity and air temperature variation created comfort area and non comfort area in the room .The direction circulation of air variation created the different pattern air circulation in the room.

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