Yun, Long
(National Research Center of Pumps, Jiangsu University)
,
Rongsheng, Zhu
(National Research Center of Pumps, Jiangsu University)
,
Dezhong, Wang
(School of Mechanical Engineering, Shanghai Jiaotong University)
Pumps are essential machinery in the various industries. With the development of high-speed and large-scale pumps, especially high energy density, high requirements have been imposed on the vibration and noise performance of pumps, and cavitation is an important source of vibration and noise excitat...
Pumps are essential machinery in the various industries. With the development of high-speed and large-scale pumps, especially high energy density, high requirements have been imposed on the vibration and noise performance of pumps, and cavitation is an important source of vibration and noise excitation in pumps, so it is necessary to improve pumps cavitation performance. The modern pump optimization design method mainly adopts parameterization and artificial intelligence coupling optimization, which requires direct correlation between geometric parameters and pump performance. The existing cavitation performance calculation method is difficult to be integrated into multi-objective automatic coupling optimization. Therefore, a fast prediction method for pump cavitation performance is urgently needed. This paper proposes a novel cavitation prediction method based on impeller pressure isosurface at single-phase media. When the cavitation occurs, the area of pressure isosurface Siso increases linearly with the NPSHa decrease. This demonstrates that with the development of cavitation, the variation law of the head with the NPSHa and the variation law of the head with the area of pressure isosurface are consistent. Therefore, the area of pressure isosurface Siso can be used to predict cavitation performance. For a certain impeller blade, since the area ratio Rs is proportional to the area of pressure isosurface Siso, the cavitation performance can be predicted by the Rs. In this paper, a new cavitation performance prediction method is proposed, and the feasibility of this method is demonstrated in combination with experiments, which will greatly accelerate the pump hydraulic optimization design.
Pumps are essential machinery in the various industries. With the development of high-speed and large-scale pumps, especially high energy density, high requirements have been imposed on the vibration and noise performance of pumps, and cavitation is an important source of vibration and noise excitation in pumps, so it is necessary to improve pumps cavitation performance. The modern pump optimization design method mainly adopts parameterization and artificial intelligence coupling optimization, which requires direct correlation between geometric parameters and pump performance. The existing cavitation performance calculation method is difficult to be integrated into multi-objective automatic coupling optimization. Therefore, a fast prediction method for pump cavitation performance is urgently needed. This paper proposes a novel cavitation prediction method based on impeller pressure isosurface at single-phase media. When the cavitation occurs, the area of pressure isosurface Siso increases linearly with the NPSHa decrease. This demonstrates that with the development of cavitation, the variation law of the head with the NPSHa and the variation law of the head with the area of pressure isosurface are consistent. Therefore, the area of pressure isosurface Siso can be used to predict cavitation performance. For a certain impeller blade, since the area ratio Rs is proportional to the area of pressure isosurface Siso, the cavitation performance can be predicted by the Rs. In this paper, a new cavitation performance prediction method is proposed, and the feasibility of this method is demonstrated in combination with experiments, which will greatly accelerate the pump hydraulic optimization design.
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문제 정의
In order to solve the problem of cavitation fast prediction, this paper focus research on cavitation prediction method based on pressure isosurface in single-phase.
The method and theory have not yet been established, and an accurate prediction method is still need to be verified. This paper will focus the cavitation characteristics of the model pump to find a rapid method to predict the cavitation method.
All these features are only related to the pump impeller. This research is based on numerical simulation of pump with water medium. The relationship between the pressure isosurface of the impeller and the NPSHr is established.
제안 방법
(1) The design concept of the method is that when the minimum pressure in the liquid is lower than the vaporization pressure, pump cavitation inception occurs. Usually cavitation occurs in the low pressure region in the liquid flow field.
The cavitation performance test is carried out on the closed test platform. The measurement error of the main measuring instrument is 0.
The design concept of the method is that when the minimum pressure in the liquid is lower than the vaporization pressure, pump cavitation inception occurs. Usually cavitation occurs in the low pressure region in the liquid flow field.
This shows that the noise level is closely related to the cavitation performance. This hypothesis will be verified by subsequent cavitation vibration and noise tests, and the initial cavitation will be assessed by analyzing the vibration or pressure pulsation characteristics by noise measurement or pressure pulsation measurement.
The existing cavitation performance calculation method is difficult to be integrated into multi-objective automatic coupling optimization. This paper proposed a new cavitation performance prediction method, and the feasibility of this method is demonstrated in combination with experiments. This method will greatly accelerate the pump hydraulic optimization design.
이론/모형
In order to solve the problem of cavitation prediction, this paper proposes a cavitation performance method for multi-objective automatic optimization. The prediction method of the pump cavitation performance is based on pressure isosurface area ratio at the cavitation condition.
This paper proposes a hypothesis called the single-phase flow pressure isosurface initial cavitation prediction hypothesis.
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