| The main drive system is the core component of reciprocating compressor, whose performance of dynamics, hydrodynamics as well as heat transfer not only directly affects the reliability and stability of the compressor, also limits the efficiency of transmission system and the no-failure lifetime of the machine. Consequently, the performance analysis on dynamics, hydrodynamics and heat transfer has always been an important part of theoretical basis for the design of the main drive system. For a long time, nearly all studies of the main drive system concerning the behaviors of dynamics, hydrodynamics and thermodynamics, nevertheless, have focused on their respective subject area. Interdisciplinary studies for exploring the coupling among various behaviors of the transmission system, as well as further improvement in the accuracy of the theoretical analysis, accordingly, are of great significance in theory and practice.At the beginning of this dissertation, based on the mass and energy conservation principles, a mathematical model of working process in a reciprocating compressor with certain assumptions, is established and resolved by mathematical programming, and the p-V diagram has been drawn. The influence of the valve’s dynamic parameters such as valve’s stiffness and quality on the variations of gas pressure in air cylinder and indicator diagram have mainly been discussed in this paper.With application of virtual prototype technology, a simulation model for crankshaft ball bearing system is built on the premise of detailing the stress condition in the system, the dynamical behavior of which is worked out with co-simulation of ADAMS and MATLAB. Considering the elastic deformation of V belt, equivalent model based on stiffness of the belt is put forward in order to resolve the difficulties caused by the establishment of dynamics simulation model by ADAMS. The results of simulations reveal that:Firstly, the elastic deformation of crankshaft is relevant to the distribution of radial displacement and radial bearing reaction of main bearings, the regularity of which is influenced by stiffness coefficients of supporting bearing and the vigor imposed on the shaft; Secondly, the influence of elasticity of V belt on horizontal component of radial bearing reaction far outweigh that of vertical component. In addition, the elasticity plays various roles on radial displacement in horizontal directions of the following three cross-sections of crankshaft, which affects the displacement most in the section of the vigor imposed on the shaft, the section of main bearing close to the side of the belt pulley does less, and the same section in the other side does the least.Kinetic experiment of the main drive system has been carried out on the self-developing platform based on a type W reciprocating piston compressor. With the aid of above test data, dynamic characteristics of the transmission system involving axis orbit of crankshaft, radial bearing reaction as well as p-V diagram are thoroughly investigated. The results of simulation agree well with that of tests, saying that the main affecting factors of axis orbit of crankshaft and radial bearing reaction include stiffness coefficients of supporting bearing, elasticity of belt, and gas force.From the views of systems, an integrated scheme of research to explore the mechanisms involved in interaction among dynamics, hydrodynamics and heat transfer of main drive system is presented. Indicative proposal concerning coupling relations and decoupling method of multidisciplinary behaviors of main drive system, incidentally, is developed, which laid the foundation for the settlement of the issue on interdisciplinary coupling analysis. |
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