This paper demonstrates the design of an electric trike’s energy management system for a goods delivery service via various possible component configurations. A model of the energy management system was first developed based on general engineering vehicles’ equations using Matlab software. Various component configurations, such as the usage of two battery types (lithium iron phosphate (LFP) and lithium nickel cobalt aluminum oxide (NCA)), implementation of three braking strategies (full mechanical, parallel, and series strategies), the presence of a range extender (RE), and various masses of range extenders were simulated by using the model. The driving cycle of the e-trike as input data in the simulation was obtained by driving the vehicle around Bandung City. Speed, distance, and elevation were obtained by using GPS-based software. The simulation results showed that the most efficient and effective component configuration was to use the serial regenerative braking strategy with no RE equipped. This configuration achieved an efficiency of 18.07 km/kWh. However, for a longer route, the usage of a 20-kg RE was required to prevent the state of charge drop below 30%. The NCA with serial regenerative braking and 20-kg RE had an efficiency of 17.47 km/kWh for the complete route.
Proper orthogonal decomposition (POD) is a coherent structure identification technique based on either measured or computed data sets. Recently, POD has been adopted for the analysis of the in-cylinder flows inside internal combustion engines. In this study, stereoscopic particle image velocimetry (Stereo-PIV) measurements were carried out at the central vertical tumble plane inside an engine cylinder to acquire the velocity vector fields for the in-cylinder flow under different experimental conditions. Afterwards, the POD analysis were performed firstly on synthetic velocity vector fields with known characteristics in order to extract some fundamental properties of the POD technique. These data were used to reveal how the physical properties of coherent structures were captured and distributed among the POD modes, in addition to illustrate the difference between subtracting and non-subtracting the ensemble average prior to conducting POD on datasets. Moreover, two case studies for the in-cylinder flow at different valve lifts and different pressure differences across the air intake valves were presented and discussed as the effect of both valve lifts and pressure difference have not been investigated before using phase-invariant POD analysis. The results demonstrated that for repeatable flow pattern, only the first mode was sufficient to reconstruct the physical properties of the flow. Furthermore, POD analysis confirmed the negligible effect of pressure difference and subsequently the effect of engine speed on flow structures.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.