Open AccessA New Method to Identify the Diesel Engine Modal Parameters based on Self-Excitation
Author(s) -
Biao Hou,
Xing Liu,
Jiheng chen,
Feng Liu,
Ye Tian,
Jingsong Tan
Publication year - 2020
Publication title -
iop conference series. materials science and engineering
Language(s) - English
Resource type - Journals
eISSN - 1757-899X
pISSN - 1757-8981
DOI - 10.1088/1757-899x/825/1/012039
Subject(s) - finite element method , modal , diesel engine , modal analysis , vibration , diesel fuel , stiffness , structural engineering , automotive engineering , excitation , modal testing , computer science , engineering , mechanical engineering , acoustics , physics , materials science , electrical engineering , polymer chemistry
At present, the methods to study the dynamic characteristics of diesel engine structure include finite element analysis method and experimental analysis method. Among, 60% of the structural stiffness and 90% of the damping ratio of the whole diesel engine come from the joint part, and the dynamic characteristics of the joint part of the diesel engine are very complex, so it is difficult to establish an accurate finite element model, and the results of finite element analysis methods are often not accurate. For the experimental analysis method, it is mainly divided into the traditional Experimental Modal Analysis method (EMA) and the Operational Modal Analysis (OMA). The EMA it alays needs to measure the excitation force of the diesel engine and the vibration response of the structure, simultaneously. And the influence of motion factors on the structure dynamics cannot be considered. The structure is excitated by the working environment, and only analyzes the modal parameters of the structure with the vibration response. Few scholars analyze the OMA for diesel engines. This paper proposes a new method to identify the modal parameters of diesel engine based on dry run. In this paper, the design and research of the motion law of the air-running self-excitation is carried out, and the validity of the method is verified.