Analysis on Vibration Conductivity in Walls of Hydropower House Based on Power Flow Theory

Abstract

Basing on the theory of power flow, frequency response analysis was acted on in a hydropower house under dominant frequency with measured data of Three Gorges Station in spiral case and draft tube. Power flow in walls was calculated by APDL procedure and the properties were analyzed. The conclusion is that longitudinal wave is the main method in walls of the powerhouse, energy is reflected and stacked at the top of the walls. Displacement along the river changes and power flow in walls decays obviously. Intensity of vibration origin and distance between the vibration and the wall are both the influencing factors，increasing the stiffness of buttressed walls takes the role of limiting flexural wave and shear wave effect

Study of the Vibration Transmission and Path Recognition of an Underground Powerhouse Using Energy Finite Element Method

“…In previous study [1], the transmission in the coupling structure, such as the main and auxiliary underground powerhouses, was confirmed as being filler in the structural joints and the foundation rock under the powerhouse. However, the amount of power that would be conducted by the rock or filler was not previously reported.…”

“…The conductivity of different fillers (asphalt wood plate, rubber plate, and closed-cell foam plate) is always less than 10%. A closed-cell foam plate was chosen as the fill material for the structural joints in this study [1], and the power flow solution for the nodes located on the structural joint at 1288.0 m between the main and auxiliary powerhouse floors is shown in Figure 2. It was obvious that the power flow peak on the main powerhouse side was located near the columns of the floor boundary but did not have a uniform distribution.…”

“…When running turbine machines, the auxiliary powerhouse absorbs the vibration energy from the main powerhouse. This energy may induce local resonance on the auxiliary powerhouse floors and walls, harming the equipment and other aspects of the structure [1,2]. Up to now, a number of studies have been made on the vibration of powerhouse structure under pressure fluctuation, but most of them only examined stress and displacement of the main powerhouses [3,4]; there were less related researches on auxiliary powerhouse and on the path of vibration transmission.…”

Multiple-TMD-Based Structural Vibration Control for Pumped Storage Power Plants

“…For PSPPs, the rotating speed of the head and pump turbine will increase significantly, further intensifying the vibration response [8,9]. In recent years, the operation of many large hydropower units has resulted in costly downtime due to vibration problems, such as cracking of key components [10,11]. In order for a pumped storage plant to be cost-effective, the plant must have good reliability.…”