Using the model proposed the detailed steam, wall and flue gas temperature distribution over the entire superheater can be determined. The numerical model of the superheater developed in the paper can be used for modeling of the superheaters with complex flow arrangement accounting scales on the internal tube surfaces. developed modeling technique can especially be used for modeling tube heat exchangers when detail information on the tube wall temperature distribution is needed.
The finite volume method was used to solve partial differential equations describing flue gas, tube wall and steam temperature. It was assumed that the inner tube surfaces are covered by a thin layer of scale deposits. Scale deposits were assumed to be present on the internal tube surfaces. As the location goes deeper into the surrounding strata from the roadway surface, the unever distribution effect of rock temperature diminishes and approaches an even distribution gradually.Ī mathematical model of the steam superheater exchanger with distributed parameters has been developed. The temperature distribution in the strata rock and its variation with the elapsed time at different wetness factors were discussed, The non-uniform distribution of heat transfer coefficient on rock surface has a large effect on the rock temperature distribution near airway surface. The distributions of air temperature is similar to that of moisture content in the locally ventilated working face, and the variations in sensible heat and latent heat from the surface of the roadway into the working face with time and wetness factors were analyzed, with the increase of wetness factor, latent heat flux increases, sensible heat flux decreases, and the total heat flux increases. The 3-dimensional k-ε turbulent flow model was used to simulate heat-and mass-transfer in a heading face with forcing auxiliary ventilation system. Based on the results of the research, assessment of the impact of heat emission from coal on the air temperature within longwall faces developing steep seams is given. There is also a new approach for recognition of heat transferring surfaces from a coal seam and developed space as for faces using pneumatic hammer and combining technologies of coal extraction. Besides, there are engineering methods for calculation of heat emission from coal within faces under border condition of first and third types. There is a mathematical model for convective heat exchange between air and fossil in faces that develop steep coal seams, which includes a number of simplifying assumptions as well. At the same time, in face with steep occurrence of seams, where delivering of material is affected by gravity force, one should consider convective heat exchange of coal fraction within the air stream. In faces with flat and sloping occurrence of seams the coal on conveying unit is considered a half-closed body, the surface of which provides convective heat exchange with air. In the present work we have determined difference of heat-exchange processes between fossils and air within faces during development of steep flat and sloping coal seams. The biggest error in prediction of temperature conditions is revealed in calculations of air temperature in faces developing steep coal seams, which is related to the peculiarities of technological processes taking place in excavation of coal. © 2020 FloodMap.The paper shows the need for increasing accuracy of heat calculations in choosing chilling equipment for normalization of temperature conditions in working faces.
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Notes:Before using this Flood Map application, please note that for various technical or non technical reasons the application is not guaranteed free of bugs or inaccuracies. Negative elevation means depth below sea level.ĭata Sources: Mazpzen, TNM, SRTM, GMTED, ETOPO1 The elevation layered on the map is in meters and is from sea level. By setting negative elevation, Bathymetry study is also possible.We also think that it can help in planning irrigation system and water management.It can help to perform elevation analysis of an area for any purpose like city/town planning, new construction etc.Global Warmin and Sea Levele Rise are the effects of Climate Change.Effect of sea level rise or sea level change can be seen on the map.It can also provide floodplain map and floodline map for streams and rivers.Songkong, India Flood Map can help to locate places at higher levels to escape from floods or in flood rescue/flood relief operation.Songkong, India Flood Map may help to provide flood alert/flood warning if flood water level at certain point is rising.Songkong, India Flood Map may be useful to some extent for flood risk assessment or in flood management, flood control etc.
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