Flow Field Characteristics And Parameters Optimization Research Of Fan Air Chamber

With the underground mineral resources’ mining depth increasing,lead to continuous improvement of ventilation requirements.Because of the large main fan power and long running time,so the energy consumption is very large,general account for 30%of all mine electricity.In today’s advocates against the background of sustainable development and energy saving,research on how to reduce main fan’^ energy consumption,has an important significance.This article studies from the perspective of reducing the resistance of fan’s affiliated equipment,optimize the structure parameters of fan air chamber,make a reasonable matching between fan air chamber and main fan,reduced energy loss and energy consumption,have practical significance in improve the economic efficiency of enterprises.Based on Jet theory,boundary layer theory of fluid mechanics,on the basis of analysis the wind flow state of fan air chamber,relying on a mine actual,segmented build geometry model of fan air chamber,according to the basic principle of three conservation laws model is established.Use the FLUENT to simulating its physical model,research flow field’s distribution of fan air chamber in different conditions of diffuser outlet wind speed and entry section than（the section than between diffuser outlet and fan air chamber）,proposed the concept which is stable length of flow field,provide the basis for reasonable match between main fan and fan air chamber;Moreover,fitting the formula of wind speed distribution’s stable length,against the problem of large local resistance in right angle turn,the optimized revamping measures are put forward and analyzed the effect after transformation.The research show that airflow after spray from main fan,due to have section difference between diffuser outlet and fan air chamber,will form vortex area in exports around,vortex will gradually disappear with airflow forward flow,the direction of airflow will eventually achieve consistent forward.The main factors affecting the "stable length of flow field"L is entry section than ε,and research "stable length of flow field"L under the condition of different entry section than ε and its qualitative relationship,fitting out the mathematical formula between ε and L is L = 4.844/ε^1.015-5.082,make a reasonable matching between fan air chamber and main fan.The results show that when the fan air chamber length less than"stable length of flow field",the vortex of fan air chamber cannot achieve stability,will cause superposition of local resistance in turning when the airflow flowing into the diffusion tower or shaft,greatly increase the overall energy loss;On the contrary,it will not have this effect when the fan air chamber length meet "stable length of flow field".According to the research on flow field of fan air chamber,fitting out the mathematical formula of stable length of wind speed distribution when airflow after turning is X0 =（0.49/（?）a +5.17）D.The stable length of wind speed distribution X0 is mainly related to frictional resistance coefficient a and chamber diameter D,has nothing to do with Re when it is greater than 105,summarizes the specific scope of wind speed distribution’s stable length under different frictional resistance coefficient of fan air chamber,through the measures which is right angle instead of circular arc and adding guide vane,make the local resistance and energy loss in turning part has effectively reduce,and airflow’s stable length after turning has shorten.