Study On The Effect Of Magnetic Field On Crystallization Of Tunnel Drainage Pipeline In Hard Water Zone

In this paper,how to prevent the crystallization of tunnel drainage pipeline in hard water area and how to remove crystals without damage and efficiently are studied.Firstly,the material Explorer molecular dynamics numerical simulation method is used to analyze the specific effect of magnetic field on the formation process of calcium carbonate crystal and the effect of magnetic field on the crystal form of calcium carbonate crystal under different conditions.Secondly,the influence rule of magnetic field on the main crystalline calcium carbonate of tunnel drainage pipeline in hard water area is studied by laboratory experiments.Finally,the Dashan Tunnel in Guizhou Province is extracted.The results of field test are analyzed.The main research results are as follows:(1)The magnetic field has a certain inhibitory effect on calcium carbonate crystallization in tunnel drainage pipelines in hard water area,but this inhibitory effect can be better displayed only under the effective combination of various external conditions.(2)Temperature will affect the restraint effect of magnetic field on calcium carbonate crystallization in tunnel drainage pipeline in hard water area,and there is a temperature critical value.When the temperature is lower than the critical value,the restraint effect of magnetic field on calcium carbonate crystallization in tunnel drainage pipeline is obvious.When the temperature is higher than the critical value,the influence of magnetic field on calcium carbonate crystallization will gradually become smaller.However,temperature has no obvious effect on the crystalline form of calcium carbonate in tunnel drainage pipeline in hard water area.Of course,in practice,it will also be affected by the material of the tunnel drainage pipe and the flow velocity in the tunnel drainage pipe.(3)Flux density will affect the restraint effect of magnetic field on calcium carbonate crystallization in tunnel drainage pipes in hard water area.When the flux density is about 0.1T,the restraint effect of magnetic field on calcium carbonate crystallization in tunnel drainage pipes is more significant.When the flux density is less than 0.1T,the restraint effect of magnetic field on calcium carbonate crystallization becomes better and better with the increase of magnetic flux density.When the magnetic field exceeds 0.1T or so,the inhibiting effect of magnetic field on the crystallization of calcium carbonate is no longer enhanced,and the crystallization of calcium carbonate is basically the same as that of 0.1 T or so.Of course,in practice,it will also be affected by the material of the tunnel drainage pipe and the flow velocity in the tunnel drainage pipe.(4)Under certain conditions,the magnetic field can change the crystal form of calcium carbonate and make the crystal form of calcium carbonate develop from stable structure to unstable state.Specifically,under the same conditions,when the magnetic flux density is less than 0.5T or so,the crystal form of calcium carbonate becomes more and more unstable.When the magnetic flux density is more than 0.5T,the influence of magnetic field on the crystal form of calcium carbonate becomes more and more unstable.The crystalline form is almost the same as that of about 0.5T when it is no longer reinforced.