﻿ 间隙流动对集成电机泵喷推进器水动力性能影响研究
 舰船科学技术  2022, Vol. 44 Issue (8): 50-55    DOI: 10.3404/j.issn.1672-7649.2022.08.010 PDF

Effect of the gap-flow model on the hydrodynamic performance of a IMP propulsor
LI Qiao
Department of Intelligent Manufacturing, Guangdong Polytechnic College, Zhaoqing 526100, China
Abstract: When the IMP propulsor works underwater, due to the pressure difference, when the water flows through the gap flow channel, frictional power consumption will be generated in the gap. In order to understand the hydrodynamic performance of IMP propulsor more accurately, this article first analyzed the influencing factors of wheel rim friction torque, and determined the influence law of geometric parameters of different influencing factors on wheel rim friction torque, calculation results and empirical values good agreement. Based on this, the influence of the presence or absence of clearance flow on the open-water performance of the propulsor was analyzed, and the influence of different clearance parameters on the open-water performance of the propulsor in the state of clearance flow was analyzed. The results show that: the friction torque of the rim can be reduced by reducing the axial clearance, etc. The efficiency of the flow with or without clearance will first decrease and then increase with the increase of the speed. The efficiency of the model with clearance is always greater than that with no clearance model.
Key words: integrated motor pump-jet propulsor     gap-flow     frictional torque     turbulence     hydrodynamic performance
0 引　言

1 数值计算方法 1.1 几何模型

 图 1 几何模型 Fig. 1 Geometric model

1.2 基本控制方程

 $\frac {{\partial {\rho _m}}}{{\partial t}} + \frac{{\partial \left( {{\rho _m}{\mu _j}} \right)}}{{\partial {x_j}}} = 0,$ (1)
 $\frac{\partial }{{\partial t}}\left( {{\rho _m}{\mu _i}} \right) + \frac{{\partial \left( {{\rho _m}{\mu _i}{\mu _j}} \right)}}{{\partial {x_j}}} = - \frac{{\partial p}}{{\partial {x_i}}} + \frac{\partial }{{\partial {x_j}}}\left[ {\left( {\nu + {\mu _t}} \right)\left( {\frac{{\partial {\mu _i}}}{{\partial {x_j}}} + \frac{{\partial {\mu _j}}}{{\partial {x_i}}}} \right)} \right] 。$ (2)

1.3 间隙模型

 ${C_M} = 1.03{\left( {h/{r_1}} \right)^{0.3}}{{{{Re}}} ^{ - 0.5}}，\left ( {400 ＜{{{Re}}} ＜ 10000} \right) ，$ (3)
 ${C_M} = 0.065{\left( {h/{r_1}} \right)^{0.3}}{{{{Re}}} ^{ - 0.2}}，\left( {{{{{{Re}}}}} ＞ 10000} \right) ，$ (4)
 ${C_M} = {M \mathord{\left/ {\vphantom {M {0.5{\text{π}} \rho {\omega ^2}}}} \right. } {0.5{\text{π}} \rho {\omega ^2}}}{r_1}^4h 。$ (5)

 图 2 计算域模型 Fig. 2 Computational domain model

Daily为了进一步研究同轴圆柱、内旋转圆柱和外静止圆柱的摩擦扭矩，进行一系列的实验研究扭矩随轴向间隙比是如何变化的。结果表明，摩擦扭矩只与间隙比和雷诺数有关，在一定的轴向间隙比下，湍流状态可分为混合层流、分离层流，混合湍流与分离湍流。当轴向间隙比 $l/{r_1}> 0.05$ 时，间隙内的流动状态为分离层流或者湍流，当轴向间隙比为 $0.01 < l/{r_1} <$ $0.05$ 时，间隙流动状态为混合湍流，此时进出端面摩擦扭矩系数为：

 ${C_M} = 0.08{\left( {l/{r_1}} \right)^{ - {1 \mathord{\left/ {\vphantom {1 6}} \right. } 6}}}{{Re} _l}^{ - 0.25} ，$ (6)
 ${C_M} = {{2M} \mathord{\left/ {\vphantom {{2M} {\rho {\omega ^2}}}} \right. } {\rho {\omega ^2}}}{r_1}^5 。$ (7)

1.4 网格划分与边界条件

 图 3 计算区域整体网格 Fig. 3 The overall grid of the calculation area

2 计算结果分析 2.1 数值方法验证

 图 4 网格对径向间隙内角速度的影响 Fig. 4 Effect of grid on angular velocity in radial gap

 图 5 径向间隙对角速度的影响 Fig. 5 Angular velocity distribution in radial gap
2.2 不同参数下间隙扭矩的变化规律 2.2.1 设计间隙时不同参数下间隙扭矩的变化规律

 图 6 进流速度和转速对轮缘摩擦扭矩的影响 Fig. 6 Rim friction torque variation with inlet velocity and rotational speed

2.2.2 不同间隙尺寸下间隙扭矩的变化规律

 图 7 不同间隙尺寸下对轮缘摩擦扭矩的影响 Fig. 7 Rim friction torque variation with different gap size
3 推进器水动力性能分析

3.1 间隙流动对转子、定子以及导管的敞水性能的影响结果分析

 图 8 集成电机泵喷推进器的水动力性能曲线 Fig. 8 IMP propulsor hydrodynamic performance curve

 图 9 集成电机泵喷推进器效率曲线 Fig. 9 IMP propulsor efficiency curves
3.2 不同间隙尺寸下集成电机泵喷推进器水动力性能的结果分析

 图 10 不同间隙尺寸下对集成电机泵喷推进器水动力性能的影响 Fig. 10 IMP propulsor hydrodynamic performance variation with different gap size
4 结　语

1）在设计间隙尺寸时，轮缘摩擦扭矩随着进流速度的增加而增加，但是增长的过程不稳定；当推进器处于泊位状态时，轮缘摩擦扭矩随转速的增大再增加。

2）轮缘外表面摩擦扭矩基本上与轴向间隙大小无关，而前后端面摩擦扭矩是随着轴向间隙的增大而增大；轮缘外表面摩擦扭矩随着径向间隙的增大而增大，而前后端面摩擦扭矩随着径向间隙的增大而减小。可通过减小轴向间隙等方法达到降低轮缘的摩擦扭矩。

3）推进器水动力性能的变化趋势在有无间隙流动时一致，整体上，有间隙流动时，其性能更佳；有无间隙流动时效率都随着转速的增加先减小再增大，有间隙模型时的效率总是大于无间隙模型。推进器总推力与轴向间隙、径向间隙的变化关联不大；推进器总转矩随着径向间隙的变化而基本上变化不大，而与轴向间隙的关系与轮缘扭矩的规律相同。

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