| With the continuous development of industry,the existence of pipe scaling has been one of the major problems affecting the pipeline transportation capacity.Therefore,it is urgent to put forward a high efficient and adaptable method of pipeline cleaning.The method of cavitation jet cleaning the pipeline is of great help and research significance to solve the problem of pipeline fouling cleaning.In this paper,the fluent simulation is used to simulate the static and movement of the cleaner based on the principle of cavitation jet in the pipeline?the combination of the three-dimensional model and the two-dimensional model?.At the same time,based on the simulation results,the idea of how to design the cleaner under different pipe diameters are provided.The main contents are as follows.:?1?The simulation of the initialization of the cleaner in the pipeline:The cleaner is regarded as static.The simulation found that the water inflows into the cleaner process.First,the cavitation occurs on the first group of leaves of the cleaner.As the flow continues to flow into the second groups of blades,the cavitation of the first group of blades begins to disappear,and the second sets of cavitation,and with the time The flow of water passes through the cleaner and the cavitation occurs only on the second set of blades.Taking the result of the velocity inlet5m/s as an example,the maximum vapor phase percentage of the cavitation is 0.96,the volume of the water vapor in the flow field is 1.4×10-6 m3,The maximum gas holdup tends to be steady with the increase of the inlet velocity,and the maximum value is about 0.97.The volume of water vapor increases with the inlet velocity.?2?Simulation of the translational movement of the cleaner in the tube:the simulation results show that when the cleaner moves in the tube,the two groups of the leaves of the cleaner are cavitation,and the range of water vapor is large compared to the time at rest.For the results of different inlet velocities,the larger the entrance speed is,the larger the water vapor range is.The average water vapor area of the two dimensional model entrance velocity of 4 m/s,4.5 m/s,5 m/s,5.5 m/s and 6 m/s is 1.12×10-3 m2?1.24×10-3 m2?1.62×10-3 m2?1.83×10-3 m2 and2.33×10-3 m2 respectively.It is consistent with the law when the cleaner is static.?3?.The simulation of the rotation of the cleaner in the bend pipe,when the cleaner is rotated,the cavitation lag phenomenon will be produced in the 180,90 and 45 degrees,that is,the part of the water vapor in the inner bending part is at the back of the cleaning.In the process of turning,the area of water vapor decreases with the motion first,and the maximum value of water vapor is 9.65×10-4m2?1.06×10-3m2 and 5.75×10-4 m2 for the 180 degree bend tube,the 90 degree bend tube and the 45 degree bend pipe?4?Two ways to design the washer cleaner different diameters are proposed.According to the evaluation standard of the volume of water vapor and the length of the cavitation area,the structure of the cleaner with tube radius 35mm is obtained.When the tube radius is more than35mm,the design of the cleaner is more reasonable with the design idea of equal proportion enlargement.When the tube radius is less than 35mm,the design idea of the control gap is adopted to design the cleaner.The structure is more reasonable.It provides a basis for the design of the cleaners. |
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