Numerical Simulation And Experimental Research Of Louver Influence On Marine Gas Turbine Exhaust System

For increasing the defense capability, IR suppressor is widely used inmodern design of marine engine exhaust system. By reducing thetemperature of chimney wall and exhaust gas of ship, marine infraredsuppression system can control infrared radiation of marine exhaust systemand lower the chance of being found by IR-guided(infrared-guided)weapons.Former researches focused on the main structure and flowcharacteristics of a ship IR suppressor, but paid less attention to theinfrared suppression system installing louver. This article researches theinfluence of louver on the performance of marine infrared suppressionsystem.On the one hand, FLUENT software had been used for numericalcomputation. By simplifying actual structure, calculation model had beendesigned. I simulated the flow of marine infrared suppression systeminstalling louvers with different structures at room temperature, selected the best scheme and combination in four programs, analyzed the influenceof louver vane angle on the marine exhaust system, and studied theinfluence of vane angle diversification in one louver on the infraredsuppression system.On the other hand, the research about influence of louvers withdifferent lengths on the infrared suppression system had been done byexperiment in which experimental model was designed according to thereal structure. Using the computer data acquisition system, pressure ofdifferent measuring points had been noted down. Then the mass flow andinlet pressure of whole system was calculated, and the curves about injectratio and pressure loss under louver length change had been drawn.Besides, in order to analysis the influence of louver on marineinfrared suppression system explicitly, I defined a dimensionless parameter—louver index. And the greater louver index is, the better IR suppressionsystem will be.