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Hydrogen recirculation system (HRS) is one of the main subsystems of proton exchange membrane fuel cell (PEMFC) system, and an HRS with high performance and low cost is essential to improve the fuel cell lifetime and efficiency. The ejector is becoming an effective alternative to the hydrogen circulation pump in the hydrogen recirculation system because of its small size, low cost and no parasitic power. However, the conventional ejector can only operate at the limited output power of the fuel cell. In order to improve this drawback, a hydrogen recirculation system with a separator-ejector integrated device is proposed. The hydrogen recirculation system based on the integrated device can make the space more compact, reduce the condensation effect of the piping, improve the fuel cell performance and reduce the cost. The design and integration method of the ejector and gas-water separator in this hydrogen recirculation system are introduced.

Traction batteries are operated in severe working conditions of wide temperature range as the vehicles run in different seasons and regions, which effects battery performance deeply. Investigation on the effect of temperature under such circumstances on battery performance is very significant to promote the application of traction battery. In this paper, some tests are conducted on a ternary-material lithium-ion battery at various temperatures. The cycling performance and some significant parameters are evaluated at the whole temperature range, especially at the extreme temperatures (below -10°C or above 45°C). The results show that the battery performance becomes poor obviously at low temperatures, which is reflected in the decreased terminal voltage and the faded discharge capacity, and at too high temperatures (above 45°C), power and capacity also decrease, which happens in the later period of discharge process.

Three-dimensional steady compressible turbulent flow fields in two types of inlet manifold are numerically simulated using the arbitrary Lagrangian - Eulerian (ALE) method. The effects of turbulence are represented by k-ɛ turbulence model. Intake and outflow boundaries are pressure inflow and outflow. All calculations are performed under the same inflow/outflow boundary condition. Mass flow rates of all manifold exits are calculated and compared to evaluate the manifold designs. The results indicate that the structure types of a multi-cylinder diesel engine inlet manifold have great effects on the engine discharge efficiency and CFD is a powerful tool in intake manifold design.

A Failure Mode, Effect and Criticality Analysis (FMECA) is a methodology used to define, identify and eliminate known and or potential failures in order to enhance the product's reliability and quality. The Criticality Analysis plays an important role in FMECA. A method defines the failures' priority to find the most risk area. Traditionally, in automobile industry, the criticality assessment is based on the severity (S), frequency of occurrence (O), detection (D) of an item failure. The priority of the problems is articulated via the Risk Priority Number (RPN). This number is a product of the occurrence, severity and detection, i.e., the method assumes that the occurrence, severity and detection have same importance. Additionally, the component and system can only be in either of the two states: functioning or failed. However, it does not represent reality. In fact, failure mode is of fuzzy conception.