Systematic Analysis And Device Optimization Of Capacity Regulation System Used In Reciprocating Compressors

Reciprocating compressors are wildly used in chemical and petroleum industries.With on-going changes in petrochemical processes,it's indispensable to apply capacity regulation systems to large-scale reciprocating compressors.Partial unloading capacity regulation method is one ideal means of achieving this for its full range and stepless characteristics.It can cause the power consumption to reduce in proportion to the decrease in capacity.To allow this method to be widely applicable,it's important to analyze the dynamic performance of a reciprocating compressor while its capacity is being regulated.Design optimization of the capacity regulation device is also necessary.In this paper,the dynamic performance of a reciprocating compressor with capacity regulation system was deeply studied,the influences of capacity regulation system to the compressor were evaluated.The conclusions provide a theoretical support for the design of regulation program.Besides,the structure and size of the hydraulic distributor were redesigned,the simulation of oil flow characteristic in the new hydraulic distributor was carried out.Lastly,the new hydraulic distributor's performance was evaluated with experimental methods to verify whether the new hydraulic distributor can meet the requirements of the capacity regulation system.The main study results are summarized as follows:1)The dynamic performance of reciprocating compressor with capacity regulation system was analyzed.Based on an M-type compressor prototype,the gas force in the cylinder was changed when the compressor's capacity was being regulated.Thus,the kinetic parameters for different regulation ratios were calculated for the compressor.Draw the curve of each parameter in one rotation cycle after systematic calculation.The calculated results demonstrate that,compared with the normal condition,the stepless capacity regulation system can meet the demand of safe operation of reciprocating compressors.2)Structural optimization of the new hydraulic distributor and flow field characteristics research.The hydraulic distributor was redesigned.The article completed the calculation and selection of rotary shaft,inner and outer sleeve,bearings,seals,etc.The simulation of oil flow characteristic in the new hydraulic distributor was carried out.The article gave the simulation results of velocity distribution,pressure distribution and path lines in the inner flow channels of new hydraulic distributor.3)Hydraulic performance test of the hydraulic distributor.An experimental platform was built.Data acquisition and monitoring system based on LabVIEW was designed.The performance of the new hydraulic distributor was verified from 3 aspects:the performance under rated oil pressure,the high and low pressure ratios,and the symmetry of the outlet oil pressure.The experiment results showed that the new hydraulic distributor can meet the requirements of the capacity regulation system.