4. Experiment and ComputationFigure 1 illustrates the constructed three-dimensional model of one given high-pressure reversing valve runner (Type No. D5-02-2B-AC-A01) selleck screening library by using PRO-E software, with its spatial structure gridded in fluent system. Figure 2 denotes the distribution characteristics and change processes of turbulence kinetic energy in it, the values of kinetic energy illustrated by different color sections in the left column. First the required turbulence field is simulated with SNQ-1TX-140 microturbulence generator, and a produced PVC transparent valve runner is applied for clearly observing the detailed flow process.
The specific experimental condition can be defined as follows: flow quantity is 10�C20Min/L, working pressure is higher than 20�C30MPa, flow velocity of flow field exit is faster than 10�C30cm/s, the spatial arrangement of valve runner is 150mm �� 150mm �� 30mm, together with the experimental time duration being kept as long as 2�C4 hours; all these condition parameters require precision adjustment in the interest of energy distribution modeling. Figure 1The constructed three dimensional model of target runner.Figure 2The distribution characteristics and change processes of turbulence kinetic energy in a high-pressure valve runner.As Reynolds number Re = uh/v is defined as 4700~4900, Figure 3 denotes the gridded fluid runner, and Figure 4 shows the turbulence imaging result. Through adopting finite volume method (FVM) in a staggered grid we implement a discretized data process on turbulence equation set.
By positioning those monitor points that show key fluid parameters such as pressure P, dissipation rating �� at the center of grid boundary, and the monitor points of flow velocity Dacomitinib �� on the grid boundary, we use a power function to parameterize the whole duration of data processing. Figure 3The gridded fluid section in the high-pressure reversing valve runner.Figure 4Turbulence in the runner of a high-pressure reversing valve.The exit boundary pressures of turbulence field are supposed as identical to those of external environment, whose normal gradient value is normally determined as zero. For the purpose of describing the boundary influences emerging from turbulence field wall, we assume they are from a nonslip condition. Namely, the three-dimensional motion velocities at the objective positions of turbulence monitoring points ��i(U, V, R) are defined as ��SpU = ?Acell��wall/��p.Here ��SpU denotes the corrected value of an original item, Acell denotes the area of a boundary grid which parallels a flow field section, and ��wall denotes an effective exchanging coefficient of velocity components that normal to the runner wall [21].