Modification Design And Aerodynamic Layout Method Of Marine Gas Turbine Multi-stage Compressor

With the rapid development of the current economy,marine safety and marine resources have important strategic significance for a country.As the main power equipment of a ship,the performance of gas turbines directly determines the maritime strength of a country,and multi-stage low-pressure gas As the main front-end component of the gas turbine compression system,its aerodynamic performance and stable working range are particularly important.At present,China’s marine gas turbine technology still has many difficulties to be overcome.As an important part of gas turbines,the study of the main performance parameters that have important effects on it is not thorough,such as flow coefficient,load coefficient and reaction degree.It is necessary to study the influence of these parameters.At the same time,the efficiency and surge margin of multi-extrusion compressors are important indicators of compressors.It determines the performance and operating stability of marine gas turbines.Therefore,to improve the efficiency of multi-stage compressors and broaden their stability very important.This article is based on a marine gas turbine multi-stage axial compressor,which has been modified and designed.By changing the one-dimensional load coefficient and reaction of degree of the newly designed compressor at various levels,the distribution of different load coefficients and reaction degree is studied.The effects of interstage matching of multi-stage compressors and the use of the transmissible vane method widened the low-mode surge margin of the modified machine.First,through careful research and analysis of a mature marine multi-stage axial compressor,based on the one-dimensional design,the meridian runner geometry basically consistent with the prototype is obtained,and the S2 twist design and three-dimensional numerical calculation are performed on it.The three-dimensional calculation results repeatedly and iteratively modify the one-dimensional and S2 design parameters of the compressor to obtain a new modified multi-stage compressor.The results show that after the modification of the multi-stage compressor,the surge margin of the design point reached25.565%,which was 3.565% higher than the prototype,and the design point efficiency reached 88.63%,which was 2.13% higher than that of the prototype.The vibration margin has reached 11.278%,which meets the requirements of retrofit design.Then,the flow field,aerodynamic parameters and surge margin of multi-stage compressors with different load coefficient distributions are analyzed.The effects of different distributions of load factors between stages on the performance and stability of multi-stage compressors were studied.Finally,by changing the reaction degree of each stage of the modified design compressor,the effects of low and high reaction of degrees on multi-stage compressor stages and between stages are studied,especially the efficiency and stability of multi-stage compressors.This paper also briefly introduces the transmissible vane method,and uses this method to widen the surge margin of the compressor under low operating conditions.