Study On Structure And Hydraulic Performance Of Micro-Irrigation Lateral Flow Regulator

The capillary flow regulator not only improves irrigation uniformity and safty reliability of the whole irrigation syste,but also convenients for design and management.Besides,it posesses better advancement andapplicability.Therefore,It is significate for us to research and develop the flow regulator with excellent performance.At present,the research and development of the Capillary flow regulator depends mainly on the traditional ways that are the designers'experience and repeatedly hydraulic performance tests of the samples.However, the inner flow statuts and deformation conditions of the Elastomer could not obtained directly as well as the theoretical research on the flow regulator is limited to the basic mechanics analysis. These years, Numerical Simulation Methoddeveloped rapidly and acheived a preferable theoretical results by applied to various fields widely, CFD numerical simulation method has been more applied to emitters theoretical research and product development,moreover,it has provided technical support for structure design and performance improvement.Based on many relative document data,the paper conducted the hydraulic performance of capillary flow regulators under the conditions of free and pressure outflow, analyze sections of the core body, the rigidity of the elastomer and so on the key technical parameters who influnced the internal flow status;meanwhile,considered the coupling effect between the fluid and elastomer of the internal structure(That is the elastomer produces distortion under the effect of the fluid loading,wherease,the deformation of the elastomer influences the flow field in turn).Therefore,the paper choses the finite element software ADINA which completely possesses coupling analysis function to do the simulation research of the capillary flow regulator.In view of the above problems , this paper has done the following exploration and has achieved the initial results:(1)Through the hydraulic performance tests of the five different capillary flow regulators under the conditions of free outflow, the pressure and flow relationship and the flow stance index can be fitted that the O type regulator compensation effect is not obvious and the pressure regulation and steady flow is disability compared with the other regulators whose inner regulation body uses the core and the elastic colloid.Besidest,the research pressure difference tests of the regulator with better hydraulic performance show that the differential pressure between entry and exit of regulator have effect on its hydraulic performance to some extent.That is to say that when the differential pressure between entry and exit increase,the regulator has better compensation ability and flow regulation effect.(2)Contrast testing studying on the main parameters which influnce the hydraulic performance of the flow regulator, we obtained that it is a great impecct on the hydraulic performance of the flow regulator when regulate the section design of the core body intake and the size of the elastomer rigidity . When other structure parameters are the same,the relations between the excess flow of the flow regulator and the area of the core body sections are negative while the rigidity of the elastomeric are positive.(3)Utilizing the ADINA software which based on finite element method,the paper not only simulating analyzed the flow regulator two dimensional axisymmentric fluid-structure interaction,but also established the fluid model and elastomer model respectively during the ADINA fluid and structural modle. Then,it made a numerical simulation by using Mooney Rivilin model supplied by the ADINA material database when the fluid was set at SST k ?ωturbulence model as well as the elastomer was set at silica gel material. Through the FSI analysis for fluid and structure model at the ADINA FSI solvers, I acquired the turbulence flow field distribution and elastomer deformation process of the flow regulator when coupling interaction considered. It Intuitive reflects that the process of the regulation steady regulate flows under the condition of the intake's pressure variation of the flow regulator.