# A Performance Test and Internal Flow Field Simulation of a Vortex Pump
## 7 Comprehensive Analysis of Research Results  
Based on the CFD numerical calculation and experimental results, we can carry out a comprehensive analysis of the internal flow rules of the vortex pump  
Due to the unique structure and working principle of the vortex pump (i.e., the use of a semi-open impeller), the impeller and vortex chambers are fully open and connected, and the vortex chamber and pump outlet are connected through a channel. Carrying on with the flow field analysis, we must consider the concept of potential strength; i.e., the flow field of gravity and centrifugal inertia forces. The unequal mass force of the impeller is an important reason for the asymmetric distribution of the impeller flow field and the degree of disorder. In the center of the impeller, because the hub occupies the central space, in order to form a vacuum range in the 10 mm \(<r<\) 20 mm annular area (\(r\) represents the radius with the center of the impeller as the origin), the lowest point of static pressure is in the upper \(y\) = 20 mm position, up to \(-\)3.6 \(\times\) 10\({}^{4}\) Pa, and it can be inferred that bubbles are first produced in this region, while the lower static pressure remained at \(-\)2.7 \(\times\) 10\({}^{4}\) Pa or so, forming clear dropped gradient upward pressure. The pressure in the lower half of the whole impeller chamber and the vortex chamber is greater than the pressure at the corresponding position of the upper part, and the static pressure reaches a maximum of about 1.1 \(\times\) 10\({}^{5}\) Pa at the outlet of the pump body and becomes the main body of the pump head. The vacuum area is greater than the pump inlet area (pump inlet \(d\) = 32 mm). The main reason is the gravity field mass force potential function \(W=gz\); the potential energy at the lower position is greater than that at the top. In addition, the lower gravity is in accordance with the centrifugal inertial force, increasing the pressure energy in the region. The structure is mainly due to the influence of the pump's outlet. In the range of 20 mm \(<r<\) 48 mm, the static pressure of the impeller chamber and the vortex chamber grows linearly, which is influenced by the impeller and has a forced vortex property. In the range of 50 mm \(<r<\) 70 mm, the upward trend of static pressure is slowed down, which indicates that the imposition of the impeller is reduced and the steady growth of the static pressure is due to the increase in the volume of the vortex chamber and the partial kinetic energy. The hydraulic design of the radius of the solute chamber and the width of the channel is calculated by this principle, and the cross-sectional area of the flow passage is found in the determination of the optimum velocity in the flow passage. In the range of \(r>\) 20 mm, the center speed of \(v_{u}\) and the absolute speed \(v\) of the impeller almost coincide with each other, and have greater values than the speed at the center of the vortex chamber. That is, the velocity of the solute chamber lags behind the rotation velocity of the impeller, and the vortex chamber \(v_{u}\) and \(v\) almost coincide. It can be seen that the width of the solute chamber should not be designed too wide under the premise of ensuring passing capacity; otherwise, the delay of the chamber velocity will increase. Within the radius of the impeller, \(v_{u}\) is approximately equal to the circumferential velocity of the impeller with the same radius. The \(v_{umax}\) is approximately 14.3 m/s, which is equal to the circumferential velocity (\(v_{u}\) = 14.326 m/s) near the outer edge of the impeller. It can be shown that numerical simulation achieves sufficient accuracy. In the range of 20 mm \(<r<\) 48 mm, the center of \(v_{u}\) and \(v\) of the impeller rise almost linearly, and the center of the vortex chamber rises to approximately a parabola. In the range of \(r>\) 48 mm, the center of the vortex chamber is of approximately parabolic descent, and the partial kinetic energy is converted to pressure energy.