Development And Application Of Calculating Software For Resistance Balance In Ventilation Dust Removal Pipe Network

With the rapid development of industrialization,countries all over the world have been paying increasing attention to the problem of atmospheric contamination.The problems of pollution faced by our country are quite serious,especially the dust pollution of the air,which requires a lot of factories to equip with a large number of ventilation and dust removal systems.However,there are still many issues to be solved for the current ventilation and dust removal systems,especially for large-scale ventilation and dust removal pipe network,the air volume in the pipe network is difficult to debug due to its complex structure,multiple branch lines and many ventilation points.Provided that the air volume in the pipe does not meet the requirements,the ventilation and dust removal system will not meet,either.In addition,when using the assumed flow velocity method for performing the design of large-scale ventilation and dust removal pipe network and calculation of the resistance balance at the nodes,there are problems such as lengthy steps,confusing data records and complicated calculations.The design and modification of drawings are also complicated.Therefore,it is of great significance to effectively deal with the problems such as the rational distribution of air volume in the ventilation and dust removal system,simplified calculation and data records,and output drawings rapidly and accurately.Visual Basic6.0 was used to develop the software for calculating the resistance balance of the ventilation and dust removal pipe network in this study.The principal part of the software is the design calculation and balance calculation of the ventilation and dust removal pipe network.The balance calculation part adopted the adjustment of the diameter of the branch pipe,the addition of a plug valve to change the valve opening and the use of adjustable aperture plate resistance balancer which only replaces aperture plate inserts with different aperture ratios,so that the nodes reach resistance balance(the resistance of the node is less than 10%).At the same time,the software was connected to Microsoft Access software to establish a database to realize the storage and management of relevant operating parameters,design calculations,and balance calculation results.Connecting the database with Excel enables the data to be exported in the form of an Excel spreadsheet and can realize the mutual communication with AutoCAD.The conclusions are summarized as follows:(1)The simple and practical software interface is user-friendly,and does not have strong requirements for users’ relevant professional knowledge.Users just need to input,design,query,add,and delete parameters on the software interface.In the design of the ventilation and dust removal pipe network,especially for the large pipe network with many ventilation points and many nodes,only design parameters need to be input to perform design calculation and balance calculation,which is convenient,fast,and accurate.Meanwhile,the software was connected with Excel to output the relevant data to facilitate the recording of data.(2)With respect to balance calculation,this software uses pipe diameter adjustment,flapper valve adjustment and adjustable orifice plate type resistance balancer.Such methods of adjustment only need to redistribute the air volume,rather than change the total design air volume or replace the equipment.In comparison with the increase of the fan air flow rate or the transformation of the pipe network previously,the balanced ventilation and dust removal pipe network not only can ensure the effect of dust removal,meet the environmental protection requirements,but also save investment and save energy.(3)When using the adjustable orifice plate resistance balancer to adjust the resistance,the adjustment of resistance was achieved just by replacing the orifice plate inserts with different aperture ratios,which correspond to different specific local resistance coefficients values.When resistance of the pipe network gets change,it is more advantageous to replace the orifice plate inserts than to replace the entire resistance balancer in terms of cost savings and material cost savings,and it reduces the cumbersome work such as debugging compared to other valve adjustment approaches.(4)This study uses this software to communicate with AutoCAD and Excel,forming a circuit on the system diagram of drawing ventilation and dust removal pipe network on which the result of balance calculation can be reflected in time,which greatly improves design efficiency and accuracy.