Analisi dell'introduzione di tecniche additive nel processo produttivo di airbox per il settore automotive

Analisi dell'introduzione di tecniche additive nel processo produttivo di airbox nel settore automotive, attraverso lo studio della tecnologia additiva e delle principali tecniche che ne fanno parte. Valutazione delle capacità delle tecniche additive per confrontarle con tecniche di produzione tradizionale, attraverso l'analisi prestazionale, dei costi e dei tempi di produzione.

A Theoretical and Experimental Study of Resonance in a High Performance Engine Intake System: Part 1

The unsteady gas dynamic phenomena in engine intake systems of the type found in racecars have been examined. In particular, the resonant tuning effects, including cylinder-to-cylinder power variations, which can occur as a result of the interaction between an engine and its airbox have been considered. Frequency analysis of the output from a Virtual 4-Stroke 1D engine simulation was used to characterise the forcing function applied by an engine to an airbox. A separate computational frequency sweeping technique, which employed the CFD package FLUENT, was used to determine the natural frequencies of virtual airboxes in isolation from an engine. Using this technique, an airbox with a natural frequency at 75 Hz was designed for a Yamaha R6 4-cylinder motorcycle engine. The existence of an airbox natural frequency at 75 Hz was subsequently confirmed by an experimental frequency sweeping technique carried out on the engine test bed. A coupled 1D/3D analysis which employed the engine simulation package Virtual 4-Stroke and the CFD package FLUENT, was used to model the combined engine and airbox system. The coupled 1D/3D analysis predicted a 75 Hz resonance of the airbox at an engine speed of 9000 rpm. This frequency was the induction frequency for a single cylinder. An airbox was fabricated and tested on the engine. Static pressure was recorded at a grid of points in the airbox as the engine was swept through a speed range of 3000 to 10000 rpm. The measured engine speed corresponding to resonance in the airbox agreed well with the predicted values. There was also good correlation between the amplitude and phase of the pressure traces recorded within the airbox and the 1D/3D predictions.

A Theoretical and Experimental Study of Resonance in a High Performance Engine Intake System: Part 2

The unsteady gas dynamic phenomena in a racecar airbox have been examined, and resonant tuning effects have been considered. A coupled 1D/3D analysis, using the engine simulation package Virtual 4-Stroke and the CFD package FLUENT, was used to model the engine and airbox. The models were experimentally validated. An airbox was designed with a natural frequency in the region of 75 Hz. A coupled 1D/3D analysis of the airbox and a Yamaha R6 4 cylinder engine predicted resonance at the single-cylinder induction frequency; 75 Hz at an engine speed of 9000 rpm.

Besonderheiten bei der Auslegung und Gestaltung lasergesinterter Bauteile

Mit der Entwicklung der losgrößenunabhängigen, additiven Fertigungsverfahren eröffnen sich vollkommen neue Wege zur Realisierung von komplexen Integralbauteilen bei niedrigen Stückzahlen. Bei der Bauteilgestaltung müssen (verglichen mit traditionellen Herstellverfahren, beispielsweise Spritzgießen) weniger Fertigungsrestriktionen beachtet werden. Dennoch ist die Gestaltungsfreiheit nicht unbegrenzt. In diesem Beitrag werden basierend auf dem Gedanken des Fertigungsgerechten Konstruierens Möglichkeiten und Herausforderungen bei der Gestaltung von additiv gefertigten Bauteilen herausgestellt. Darauf aufbauend werden Potenziale aufgezeigt, wie Produktentwickler in Zukunft bei der Auslegung und Gestaltung solcher Produkte unterstützt werden können.