Simulation of the rolling of stator vanes Harm Wisselink
Contact info: Harm Wisselink Han Huetink Martien van Dijk Andre van Leeuwen h.h.wisselink@wb.utwente.nl j.huetink@wb.utwente.nl ID_eldim@eldim.nl ID_eldim@eldim.nl Introduction ELDIM manufactures among others stator vanes for the compressor of an aero engine (figure 1). These vanes are produced by a cold rolling process. The development of a rolling process for a new type of vane can take several cycles of trial and error, before all requirements are fulfilled. from strips of sheet metal
Analysis of guillotining and slitting, finite element simulations
Guillotining and slitting are two sheet metal cutting processes, which produce long straight cuts and can be seen as stationary processes. The analysis of these two processes is the subject of this thesis. This research project is part of a cluster of IOP projects on sheet metal cutting, originating from industrial requests for more fundamental knowledge, as sheet metal cutting is still mainly based on experience and trial and error. The objective is to develop models of guillotining and slitting to increase the insight and to contribute to the quality and productivity of these shearing processes.
A Critical Assessment on Functional Attributes and Degradation Mechanism of Membrane Electrode Assembly Components in Direct Methanol Fuel Cells
Direct methanol fuel cells (DMFC) are typically a subset of polymer electrolyte membrane fuel cells (PEMFC) that possess benefits such as fuel flexibility, reduction in plant balance, and benign operation. Due to their benefits, DMFCs could play a substantial role in the future, specifically in replacing Li-ion batteries for portable and military applications. However, the critical concern with DMFCs is the degradation and inadequate reliability that affect the overall value chain and can potentially impede the commercialization of DMFCs. As a consequence, a reliability assessment can provide more insight into a DMFC component’s attributes. The membrane electrode assembly (MEA) is the integral component of the DMFC stack. A comprehensive understanding of its functional attributes and degradation mechanism plays a significant role in its commercialization. The methanol crossover through the membrane, carbon monoxide poisoning, high anode polarization by methanol oxidation, and operating parameters such as temperature, humidity, and others are significant contributions to MEA degradation. In addition, inadequate reliability of the MEA impacts the failure mechanism of DMFC, resulting in poor efficiency. Consequently, this paper provides a comprehensive assessment of several factors leading to the MEA degradation mechanism in order to develop a holistic understanding.