Analytical study of the characteristics of streams flowing from nozzles of compound-type construction

Abstract

The urgent task for oxygen converter process is the improvement of environmental indicators due to the reduction of emissions of carbon oxides into the atmosphere. It is possible due to the reduction of iron consumption and the increase of the possibility of processing scrap metal. For this, it is necessary to increase the heat content of the bath that is possible due to the use of top lances equipped with special nozzles. The article presents the results of research and analysis of the use of composite nozzles of the coherent type for this purpose. Such nozzles are the nozzles for supplying oxygen, consisting of a central nozzle and an annular peripheral nozzle surrounding it. Conducted physical and analytical studies of the features of the outflow of gas jets from compound nozzles of a coherent type of different designs (with the size of the peripheral part from 0.07 to 0.47 calibers of the central nozzle) under the conditions of 2M blowing made it possible to establish that the compound design under certain conditions can add additional obstacles and limitations of the development of the central jet (with a width of the peripheral part of 0.07 - 0.17 calibers), or to provide additional impulse with a larger width of the peripheral part. This is connected with the peculiarities of the formation of the jet in the initial area of development. Therefore, it is necessary to take into account the geometric arrangement of the central and peripheral parts relative to each other to obtain the required result of forming a complex jet with specified properties. According to the results of an analytical study of the dependence of the weight of the jet flowing out of composite nozzles of the coherent type, a mathematical expression was established for calculating the energy consumption coefficient of the jet when passing through the nozzle and an expression for calculating the weight of the jet as a necessary indicator of the momentum responsible for its power and penetrating properties. Use of established expressions make it is possible to predict the characteristics of the studied composite nozzle of the coherent type based on its geometric design and pressure indicators.