Simulation Research On Performance Of Marine Intercooled Cycle Gas Turbine

Because of the growing requirement for fighting efficiency of warship, the requirements forpower and electric energy of warship are increasing. The IPS is one of the directions of the futurewarship. Since the capacity of the power system is very small, and the changes of the load aresignificant, the power unit must possess better dynamic characteristic and higher capacity.Because of the higher capacity, less volume, lower weight, higher flexibility of the gas turbine(GT) power system, it has become one of the ideal prime power source for IPS. This paper takesthe intercooled cycle gas turbine as the research object, focusing on the analysis of the dynamiccharacteristic in power generation mode.The main works of this paper are focused on:(1) Based on modular modeling, the nonlinear mathematical model of intercooled gasturbine is established, with the volume inertial, rotation inertia of rotor and thermal inertia ofintercooler fully considered.(2) The structure of intercooler has been optimized by using Aspen Muse software. The finefficiency and heat transfer coefficient of the intercooler core is obtained throughthermodynamic calculations. A simulation model is founded based on the MATLAB/SIMULINKplatform according to mathematical model, and the dynamic characteristic of intercooler isanalyzed.(3) Components of gas turbine and overall simulation models are established based onMATLAB/SIMULINK platform. Some thermal process, such as deflating against surge,extracting air for cooling and mixture for cooling turbine, deflating against overspeed aresufficiently considered. The gas turbine is controlled by means of the speed combined withtemperature. Besides, the calculation for gas turbine on steady and dynamic conditions have beencarried in propelling and power generation mode, while the analysis is emphasized on thebehavior of gas turbine in latter mode.The results of the simulations show that when the gas turbine runs respectively in the twomodes mentioned above, the efficiency for total unit in propelling mode is higher than that in power generation mode in high condition, yet it goes to the opposite side in low condition.Because of the affection of temperature limitation curve, it is necessary to reduce the stable timeand speed fluctuation range of power turbine by multistage loading in sudden loading process; inthe process of sudden reducing load, the operation curve of low-pressure compressor is close tothe surge margin, however, it is just opposite in high-pressure compressor. Under load rejection,surge may happen in low-pressure compressor, yet air bleeding which can control the speed ofpower turbine effectively could avoid the surge occurring.