An Cold Experimental Analysis of Draught System with Chain-Grate Stoker

2011 ◽  
Vol 230-232 ◽  
pp. 1236-1241
Author(s):  
Zhi Ying Zhang ◽  
Jia Hua Lu

The study of cold state testing and evaluation analysis were carried on the practical running chain-grate stoker, which has an air-supply system with air storehouse and airtrough, to study the air-distribution, air leakage, air tightness and air governing. The result shows that horizontal air distribution across the furnace and the air tightness of the components such as the air port (damper) and airtrough are good. However the air leakage is large because of the complex structure and the high demand of integrated air tightness either in the front or the back of the stoker. The cost of the stoker is high because of large quantity of machine work after casting and high demand of installation, thus the structure should be improved.

1997 ◽  
Vol 119 (2) ◽  
pp. 120-128 ◽  
Author(s):  
J. T. Kuo ◽  
W.-S. Hsu ◽  
T.-C. Yo

One important aspect of refuse mass-burn combustion control is the manipulation of combustion air. Proper air manipulation is key to the achievement of good combustion efficiency and reduction of pollutant emissions. Experiments, using a small fix-grate laboratory furnace with cylindrical combustion chamber, were performed to investigate the influence of undergrate/sidewall air distribution on the combustion of beds of wood cubes. Wood cubes were used as a convenient laboratory surrogate of solid refuse. Specifically, for different bed configurations (e.g., bed height, bed voidage, bed fuel size, etc.), burning rates and combustion temperatures at different bed locations were measured under various air supply and distribution conditions. One of the significant results of the experimental investigation is that combustion, with air injected from side walls and no undergrate air, has the maximum combustion efficiency. On the other hand, combustion with undergrate air achieves higher combustion rates but with higher CO emissions. A simple one-dimensional model was constructed to derive correlation of combustion rate as a function of flue gas temperature and oxygen concentration. Despite the fact that the model is one-dimensional and many detailed chemical and physical processes of combustion are not considered, comparisons of the model predictions and the experimental results indicate that the model is appropriate for quantitative evaluation of bed-burning rates.


2021 ◽  
pp. 85-97
Author(s):  
A. S. Titenkov ◽  
Yu. N. Utyashev ◽  
A. A. Evdoshchuk ◽  
V. A. Belkina ◽  
D. V. Grandov

Currently, most of the fields being put into development are characterized by a complex geological structure, both in terms of section and in terms of plan. The solution of all geological tasks, including such important ones as the preparation of exploration projects, operation and effective development management, is impossible without creating models that reflect the main features of the variability of target parameters. The construction of adequate models of objects with a complex structure requires the involvement of all available information. The accuracy of the geological model is mostly determined by the accuracy of the well correlation. Paleosols are a new marker for the complex-built layers of the VAk-2 and VAk-3(1) of the Tagul field, which contributes to the validity of the correlation of the section of these layers. The reliability of the model was also improved by the use of the results of facies analysis. This analysis showed that the sedimentation of the studied objects includes channel and floodplain facies. Reservoir rock properties of these facies differ significantly. The updated model is characterized by a reduction in the oil-bearing area and the amount of reserves. The implementation of the model will optimize the project fund of wells and reduce the cost of well intervention. Economically, this means reducing capital costs and increasing the profitability of the project.


2001 ◽  
Vol 44 (9) ◽  
pp. 165-171 ◽  
Author(s):  
M. Pavageau ◽  
E.M. Nieto ◽  
C. Rey

Experiments were conducted on a two stream air-curtain prototype designed for VOC and odour confinement in a truck unloading area. The emphasis was placed on the air supply device. Measurements using tracer gas techniques were performed to assess the effectiveness of the system in terms of air tightness. Leakage flow rate was estimated for various feeding arrangements. Flow visualisations and particle image velocimetry measurements were carried out for a better understanding of the flow dynamics. Evidence was given of the improvements brought by the herein referred to, “double flux” configuration in comparison to traditional designs. After a brief description of the experimental facility and the basic principle underlying the approach developed, the main results are reported and discussed and recommendations are drawn. Considerations about where the effort will be directed in future works are provided.


Energies ◽  
2021 ◽  
Vol 14 (23) ◽  
pp. 8130
Author(s):  
Ziwen Dong ◽  
Liting Zhang ◽  
Yongwen Yang ◽  
Qifen Li ◽  
Hao Huang

Stratified air distribution systems are commonly used in large space buildings. The research on the airflow organization of stratified air conditioners is deficient in terms of the analysis of multivariable factors. Moreover, studies on the coupled operation of stratified air conditioners and natural ventilation are few. In this paper, taking a Shanghai Airport Terminal departure hall for the study, air distribution and thermal comfort of the cross-section at a height of 1.6 m are simulated and compared under different working conditions, and the effect of natural ventilation coupling operation is studied. The results show that the air distribution is the most uniform and the thermal comfort is the best (predicted mean vote is 0.428, predicted percentage of dissatisfaction is 15.2%) when the working conditions are 5.9% air supply speed, 11 °C cooling temperature difference and 0° air supply angle. With the coupled operation of natural ventilation, the thermal comfort can be improved from Grade II to Grade I.


2014 ◽  
Vol 595 ◽  
pp. 79-82
Author(s):  
De Ying Sun

There are many parts in aerospace fixing device, the 7075 - t351 brand aluminum alloy is a commonly used material of these parts [2].The material has high strength, good toughness, wear resistance and resistance to spalling corrosion resistance and other characteristics; After the machining deformation, comprehensive mechanical processing performance is good [1]. As a result, the materials are widely used in aerospace equipment. Smaller wall thickness, complex structure, multiple azimuth need processing, is the characteristics of these parts, make the individual parts machining material consumption is larger, increase the cost of the material consumption. In this paper, through the analysis of part structure and machining process, adopt to layout method, in order to improve the utilization rate of aluminum alloy sheet metal, reduce the unit cost.


Author(s):  
Hamza Begdouri ◽  
Luis Rosario ◽  
Muhammad M. Rahman

This study considers airflow simulations to evaluate the impact of different window air-conditioner locations on the thermal comfort in an office rooms (OR). This paper compares the air distribution for an office room by using computational fluid dynamics (CFD) modeling. The air distribution was modeled for a typical office room window air conditioning unit, air supply from a high pressure on the top and the low pressure exhaust on the bottom considering the existing manufacturing ratios for surface areas. Calculations were done for steady-state conditions including an occupant and a light source. The discharge angle for the supply grill of the AC unit was varied from 20 to 40 degrees. The position of the air conditioner was also varied and studied at 60%, 75% and 90% of the total height of the room. In addition the location of the occupant within the office room was varied. Predictions of the air movement, room temperature, room relative humidity, comfort level, and distribution of contaminants within the office room are shown. Analysis of these simulations is discussed. The positions of the air-conditioner unit, the inlet angle and the occupant position in the office room have shown to have important impacts on air quality and thermal comfort. Results are in good agreement with available experimental data.


2020 ◽  
Vol 866 ◽  
pp. 82-95
Author(s):  
Guang Yao Li ◽  
Yang Cao ◽  
Tao Yue Yang ◽  
Wen Qing Ma

Aiming at the problems of large temperature differences and inconsistent baking speeds at different positions in the tobacco chamber of the tobacco baking room, this paper proposes a complex structure processing technology of fan vent. according to the structure and drying principle of the baking room, ANSYS fluent simulation software was used to analyze the processing parameters of the heat flow field inside the baking room. combining the characteristics of positive and negative air supply baking, the processing and manufacturing parameters of the baking room were optimized, and then the baking comparison test was performed. The results show that: the forward and reverse air-baking method and the complex structure reduces the temperature difference in the interior of the smoke chamber; the forward and reverse air-bake method reduces the baking time by 11 hours, and reduces the coal consumption and power consumption by 12.6%, 48.5%, the standard deviation of temperature monitoring points in the baking room decreased by 44%.


2018 ◽  
Vol 149 ◽  
pp. 01093
Author(s):  
Benyamina Smain ◽  
Siham Kamali-Bernard ◽  
Kenai Said ◽  
Menadi Belkacem

Self-compacting concretes (SCC), are hyper-fluid concretes, placed without vibration and are considered as one of the most important innovations of the last decade in construction. SCCs offer many advantages, due to their exceptional characteristics of flow and filling of formwork. Their compositions require a large quantity of fines in order to limit bleeding and segregation. Hence, the use of crushed sand (SC), rich in limestone fines (CF) in the manufacture of self-placing concretes (SCC), can be considered as an alternative source of fillers. These sands reduce the cost of SCC by reducing the high demand for fillers on the one hand and on the other hand, obtaining SCC with good physical and mechanical properties. The main purpose of this paper is to examine the effect of different percentages (0, 5, 10, 15, and 20%) of (CF) in crushed sand on SCC performance. The evolution of the compressive strength, the porosity accessible to water and the migration coefficient of the chloride ions were evaluated. The Okamura method was used for the formulation of all SCC mixtures. Sand/mortar (S/M), water/cement (W / C) ratios and superplasticizer content were kept constant. The results show that (CF) reduce the compressive strength but contribute to the reduction of porosity and migration of chloride ions.


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