﻿ 基于频响函数法的海水泵动载荷对隔振系统影响分析
 舰船科学技术  2022, Vol. 44 Issue (24): 22-25    DOI: 10.3404/j.issn.1672-7649.2022.24.005 PDF

1. 武昌船舶重工集团有限公司，湖北 武汉 430060;
2. 海军装备部驻武汉地区第一军事代表室，湖北 武汉 430060

Analysis of the influence of dynamic load of sea water pump on vibration isolation system based on frequency response function method
ZHANG Sheng-le1, YING Dong2, XU Hai-qun1, QIU Fa-fu1
1. Wuchang Shipbuilding Industry Group Co., Ltd., Wuhan 430060, China;
2. The First Military Representative Office of Naval Armament Department in Wuhan, Wuhan 430060, China
Abstract: In order to master the Influence of sea pump operation on vibration isolation system, this paper adopts the transfer function calculation method, using the actual sea pump parameters and the measured mechanical impedance parameters of vibration isolation element, for the operation parameters of sea water pump in shafting system. The calculation results show that the operation of sea water pump will have a certain displacement effect on the vibration isolation system, but it will not affect the performance of the vibration isolation system.
Key words: frequency response function     sea pump operation     the displacement change     vibration level drops
0 引　言

1 频响函数计算方法基本原理

 ${{\boldsymbol{H}}_{\boldsymbol{A}}} = \left[ {\begin{array}{*{20}{c}} {H_{ii}^A}&{H_{ic}^A} \\ {H_{ci}^A}&{H_{cc}^A} \end{array}} \right] ，$
 ${{\boldsymbol{H}}_{\boldsymbol{B}}} = \left[ {\begin{array}{*{20}{c}} {H_{ii}^B}&{H_{ic}^B} \\ {H_{ci}^B}&{H_{cc}^B} \end{array}} \right]，$

 $\left[ {\begin{array}{*{20}{c}} {X_i^A} \\ {X_c^A} \end{array}} \right] = \left[ {\begin{array}{*{20}{c}} {H_{ii}^A}&{H_{ic}^A} \\ {H_{ci}^A}&{H_{cc}^A} \end{array}} \right]\left[ {\begin{array}{*{20}{c}} {f_i^A} \\ {f_c^A} \end{array}} \right] ，$
 $\left[ {\begin{array}{*{20}{c}} {X_i^B} \\ {X_c^B} \end{array}} \right] = \left[ {\begin{array}{*{20}{c}} {H_{ii}^B}&{H_{ic}^B} \\ {H_{ci}^B}&{H_{cc}^B} \end{array}} \right]\left[ {\begin{array}{*{20}{c}} {f_i^B} \\ {f_c^B} \end{array}} \right]。$

 $f_c^A + f_c^B = {F_c} ，$
 $f_i^A = F_i^A ，$
 $f_i^B = F_i^B ，$
 $X_i^A = x_i^A ，$
 $X_i^B = x_i^B ，$
 ${X_C} = x_c^A = x_c^B 。$

 $\begin{array}{*{20}{l}} & \left\{ {\begin{array}{*{20}{l}} {X_i^A} \\ {{X_c}} \\ {X_i^B} \end{array}} \right\} = \left( \left[ {\begin{array}{*{20}{c}} {H_{ii}^A}&{H_{ic}^A}&0 \\ {H_{ci}^A}&{H_{cc}^A}&0 \\ 0&0&{H_{ii}^B} \end{array}} \right] - \left[ {\begin{array}{*{20}{c}} {H_{ic}^A} \\ {H_{cc}^A} \\ { - H_{ic}^B} \end{array}} \right]\times\right.\\ & \left.{{{\left( {H_{cc}^B + H_{cc}^A} \right)}^{ - 1}}{\left[ {\begin{array}{*{20}{c}} {H_{ic}^A} \\ {H_{cc}^A} \\ { - H_{ic}^B} \end{array}} \right]^{\rm{T}}}} \right)\left\{ {\begin{array}{*{20}{c}} {F_i^A} \\ {{F_C}} \\ {F_i^B} \end{array}} \right\}。\end{array}$

2 载荷计算参数

80 t及100 t海水泵转子质量m=90 kg，转速n=2900 r/min；25 t海水泵转子质量m=11 kg，转速n=2900 r/min。平衡精度等级G按普通泵的叶轮选取6.3。经计算，3台海水泵的转子许用不平衡度（偏心距）均为： ${e_{per}} = \dfrac{{1000G}}{w} =$ $\dfrac{{30000G}}{{n\text{π}}} = 20.75$ μm；80 t及100 t海水泵转子偏心转动产生的离心力： ${F_1} = me{\omega ^2} = 172.2\;{\rm{N}}$ ；25 t海水泵转子偏心转动产生的离心力： ${F_2} = me{\omega ^2} = 21.1\;{\rm{N}}$

3 边界条件

4 实体几何模型及子结构划分

 图 1 实体模型 Fig. 1 Solid model

 图 2 子结构划分图 Fig. 2 Substructure division diagram

 图 3 子结构动力学计算节点编号 Fig. 3 Dynamic calculated node numbers of substructure

 图 4 子结构计算连接点 Fig. 4 The calculated connection node of substructure

5 计算结果

 图 5 各节点的位移响应（10～1000 Hz） Fig. 5 Displacement response of nodes (10～1000 kHz)

1）在10～100 Hz的频率范围内，各节点变形量均较大，100～1000 Hz的频率范围内，各节点变形量均较小，位移接近零变化。

2）浮筏隔振元件（7号、8号）的变形量最大不超过10 mm，随着频率增大，变形量呈减小趋势。

3）设备隔振元件（5号、6号）的变形量最大不超过6 mm，随着频率增大，变形量呈减小趋势。

4）进出口管路隔振元件（1号、2号、3号、4号）的变形量最大值达到15 mm，随着频率增大，变形量呈减小趋势。

 图 6 振级落差计算元件编号 Fig. 6 Calculated parts numbers of vibration level drop

 图 7 隔振元件振级落差计算结果（10～1000 Hz） Fig. 7 Calculation result of vibration level drop of vibration isolators (10～1000 kHz)

6 结　语

1）轴系海水系统在海水泵运行时会产生一定的位移变化，局部变化可能会超过15 mm，在系统安装、检验过程中，应严格按照技术要求规定设置隔振系统与周围结构、设备、管路等间距，以防系统工作时相碰。

2）虽然海水泵运行时会对隔振元件产生一定的位移变化，但各隔振元件的振级落差效果均较好，系统工作时位移变化不会影响隔振元件隔振效果的发挥。

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