Proton Exchange Membrane Fuel Cell Ejector Test Platform Design and Ejector Test Analysis

The hydrogen recirculation system is essential to the performance of the fuel cell system; the ejector device plays an important role in the hydrogen recirculation system. In this paper, a test platform which can simulate the fuel cell anode system is integrated for ejector performance testing. Based on the ejector test platform, an ejector device was tested under different operating conditions. The design of the ejector test platform, the test method and test process are introduced in detail. The test results of the ejector are compared with the Computational Fluid Dynamics (CFD) simulation results of different turbulence models. The results show that the standard k-e model is more accurate than other turbulence models at small and medium flow rates. At a large flow rate, the realizable k-e model has a higher simulation accuracy than other turbulence models.

The Research on Characteristics of a New Type of Marine Gas Turbine Exhaust Ejector Device

Marine gas turbine exhaust ejector device is responsible for reducing or eliminating the infrared signatures of exhaust system. In order to optimize the structure of exhaust ejector and shorten the cycle of research, it is essential to study the successful experiences on exhaust ejectors by scholars abroad. In this article two structure innovations were introduced: the nozzle structure changing from circular to rectangular and multi-stage diffuser, then a new type of marine gas turbine exhaust ejector was designed. Through simplifying the ejector model, numerical simulation was used to predict the characteristics of both the single-stage ejector and the multi-stage ejector. The result indicates the effects of structural parameters on the performance parameters. This research result has certain reference value for marine gas turbine exhaust ejector structure innovations and performance optimization.