The Design Optimization Of Crankshaft Structure On Marine High-power Reciprocating Compressor

New marine reciprocating compressors must have high power,high pressure ratio,slight vibration and environmentally-friendly with the development of marine natural gas boosting and gathering.Therefore,the effect of each component of the compressors on its overall performance should be investigated in detail.Crankshaft systems of reciprocating compressors have an effective influence on compressor performance,being the main part responsible for vibration production.The high-power reciprocating compressors are designed to run onshore;accordingly,the support of compressors cannot match the crankshaft structure parameters and there are some drawbacks such as loud noise and high vibration intensity caused by gas force,reciprocating inertia force and centrifugal force when it is used offshore.Consequently,the parameters of crankshaft structure should be changed.Combined with the project of Ministry of Industry and Information Technology(Manufacture of Marine High-power Reciprocating Compressor,[2014]506),the optimization of the crankshaft structure is studied in this paper,mainly include the following details.Firstly,the dynamic model of the crankshaft system on marine high-power reciprocating compressor was built by dynamic theory and solved by Newton-Raphson method.Then,the characters of kinematics and dynamics were analyzed.Additionally,the kinematics characteristics was solved by the theory of kinematics,and the dynamic characteristics was tested by the photoelectric rotating speed sensor and torque test system of remote sensing strain-resistor method.Then,the virtual proving ground simulation model was revised by the above result.The satisfied model was gained.Secondly,the feasibility design method with multidisciplinary and multi-objectiveoptimization is applied in the research of lightweight design and NVH performances of crankshaft in high-power marine reciprocating compressor.Opt-LHD is explored to obtain the experimental scheme and perform data sampling.The elliptical basis function neural network(EBFNN)model considering strength property,torsion vibration response and lightweight design of crankshaft is built.Deterministic optimization and reliability optimization for lightweight design of crankshaft are operated separately.Multi-island genetic algorithm(MIGA)combined with multidisciplinary co-optimization method is used to carry out the multi-objective optimization of crankshaft structure.Pareto optimal set is obtained.Finally,the uncertain optimization problem of structures containing random and interval variables is studied.Firstly,the interval expression with random parameters is gained by the confidence level.Additionally,the interval order relation,interval probability,the elliptical basis function neural network technology and multi-objective genetic algorithm are applied to construct uncertain optimization method based on random-interval hybrid parameters.And typical examples are used to demonstrate the effectiveness of the proposed method.Finally,the Opt-LHD is adopted to obtain the experimental scheme and perform data sampling.The elliptical basis function neural network considering strength property and torsion vibration response of the crankshaft is built.The uncertain multi-objective optimization(UMO)is operated on the crankshaft structure of the marine high-power reciprocating compressor.