Rectangular Plate Type Radiator Vibration Characteristic Research

The radiator composed of longitudinal vibration transducer and bending vibration plate has widely application prospects in the field of high-power ultrasound. There are two kinds of the radiator:Disk type and rectangular type. The one hand, the vibration equation of rectangular plates in bending vibration with the free boundary conditions has no analytical solution; the other hand, the vibration of rectangular plates is more complicated than the disc. Nodal line of the rectangular plate has two directions. Rectangular plate with different aspect ratio may have different mode shapes. Some nodal line was straight line, and some were bent type. So the vibration characteristics of rectangular plates are very complex.Most previous research on the rectangular plate did not consider the bending of rectangular plate nodal line. However, in practical applications, the nodal line of rectangular plate is often curved. Sometimes bending is not serious and can be ignored; but sometimes bent very serious and can not be ignored. This is a problem that must be addressed in the design of the rectangular plate radiator.If the thickness is in line with the definition of the thin plate, rectangular plate vibration mode is only related to the aspect ratio of the plate. To figure out the relationship between the nodal line and the aspect ratio, can help us design rectangular plate radiator.In this paper, we calculate25modal shapes of35rectangular plate with aspect ratio from0.6to4by the finite element method. The variation of the nodal line with different aspect ratios has obtained.3plates with different aspect ratio studied by the experimental method, and the mode shapes had obtained. The detailed work is fellow:(1) By finite element method, calculated the vibration mode of rectangular plate with different aspect ratio. Obtained the variation of the nodal line of rectangular plates with different aspect ratios. Found that some modes exist one or several special aspect ratios. When the plate aspect ratio close to a special aspect ratio, the nodal line will be curved.(2) On the basis of the previous step, study the variation of nodal line of the stripe pattern of the rectangular plate of different aspect ratios. Found some special aspect ratio of the stripe pattern. (3) Frequency variation of two types of stripes mode modal with different aspect ratio was studied.(4) The impact of Face incentives has been studied. And found that nodal line of different vibration modes with surface incentives has different impact. Nodal line of same vibration modes with different aspect ratio has different impact.(5) Rectangular plate radiator and disc-type radiator were compared. Found that the disc is more simply in appearance, and the shape of rectangular plates is relatively complex. Rectangular plate with different aspect ratio have different striped pattern. While the disc does not have this kind of change. The vibration amplitude of the rectangular plate is more uniform than the disc.