Dynamic Analysis of Upper Hydraulic Drive Control Rod Under Vibration Conditions

The paper studies the dynamic response of the hydraulically driven control rod (HDCR) under vibration conditions. The governing equation of the hydraulic driving system in a non-inertial coordinate system was deduced using a characteristic method. By comparing the analysis with the experiment, the analysis program was validated. It is shown that the response of a hydraulic driving system under a dissimilar vibration load is different. Under the condition of the pulse loading with a higher acceleration and short period, the response amplitude of the control rod mainly depends on the input displacement and increases with its increase. The response amplitude is also related to the loading direction. The pulse loading in a downward direction causes the higher response of HDCR. Under the condition of an ocean wave with a lower acceleration and long period ocean wave, the response amplitude is small, and the hydraulic drive system can keep the control rod stable by self regulating.