The Study On Vibration And Vibration Control Of The Pipeline Of Reciprocating Compressor

Reciprocating compressor is used extensively in many industrial fields such as chemical industry, iron and steel factory, petroleum industry etc., owing to its own advantages of high adiabatic effectiveness and discharge pressure. However, periodical intake and discharge in reciprocating compressor lead to air-current pulsation in the pipeline. Air-current pulsation, which gives rise to the piping vibration, not only makes control instruments and air-valves destroyed, capacity effectiveness of compressor decreased, but also is a great threat to safe production. Strong piping vibration has brought serious harms: leakage and explosion. It is one of the fundamental task to study the vibration and vibration control of the pipeline of reciprocating compressor. The following work is discussed.The development of finite element method is reviewed simply and several steps to analyze the piping structure are explained. The piping structure is divided into different elements; element stiffness matrix and element mass matrix are built up. On the basis of the combined total stiffness matrix, total mass matrix and the theory of Lagrange, the dynamical equation of the piping structure is obtained.After Subspace and Modal Analysis are applied to solve the dynamical equation, some dynamical parameters such as natural frequency,modal shape and displacements are easily acquired. FEM software ANSYS has been used to comprehensively analyze the structural modal and the harmonic response of the pipeline of reciprocating compressor. A comparison made between the results of calculating and measuring with INV-303/306 Intelligent Signal -Acquisition and Analyzer, a fairly satisfactory coincidence has been obtained.The FEM equation of acoustic wave is used to calculate the air-current natural frequency and pressure pulsation in the pipeline. As a sample, FEM has been used to analyze the air-current in the pipeline instead of transfer matrix method. At the same time, several holes have been drilled at the pipeline in order to measure the pressure pulsation in the complicated pipeline. The calculating results have been compared with the measuring results to obtain a fairly satisfactory coincidence.Some methods and criterions are given to appraise the pressure pulsation and the amplitude of the displacement. Many ways such as piping design, compressor design and acoustic filters etc., are helpful to reduce, even eliminate the piping vibration. On the basis of the above ways, the vibration of the complicated pipeline has been controlled under the safe range.