Experimental Study of L-PBF Micro-channel Surface Roughness: An Experimental Study on the Effects of Build Angle on Surface Roughness and Fluid Flow Performance in Laser-Powder Bed Fusion manufactured Micro-channels

Progress in Laser powder bed fusion manufacturing has led to greater use of Additive Manufacturing in combustion chambers/nozzles. This allows for the creation of more intricate and efficient solutions, but generates the need for a better understanding of how surface roughness in micro-channels used for engine cooling relates to build angle and...

Modelling of wall-bounded flows near a cylinder-bed junction in turbulent flow conditions using an IDDES turbulence model to asses initial particle entrainment

Due to the presence of a monopile in a turbulent flow swirling vortices, known as horseshoe vortices, can form upstream of the structure near the cylinder-bed junction. Those vortices then travel downstream of the cylinder as they are being dragged along with the current. The horseshoe vortices can scoop up bed material surrounding the cylinder,...

The feel of 3D prints: An objective and perceptual characterization of FDM surface roughness

Since the expiration of the FDM printing patent by Stratasys in 2009, Fused Deposition Modeling(FDM) printing has taken a large step towards accessible consumer 3D printing. Also, more knowledge is sought in the process of FDM printing and optimizing quality as the layer by layer deposition inevitable results in poor surface quality. This study...

Fatigue Crack Initiation Behaviour of Additive Manufactured Ti-6Al-4V

This master thesis investigates the effect of surface morphology of Selectively Laser Melted Ti-6Al-4V on fatigue performance. The literature study performed here iden- tifies roughness as one of three major causes for the decreased performance of the additive manufactured alloys (along side porosity and residual stresses). In order to eliminate...

Influence of Engineered Roughness on the Flow Instabilities in a Centrifugal Compressor

Centrifugal compressors form an integral part of automotive turbochargers. Strict emission regulations and increased engine downsizing in the automotive industry are pushing the turbocharger centrifugal compressors to provide the charged air at very lower mass flow rates. However, at low mass flow rates, the operation and application of...

Update Offshore Wind Atlas: Implementing a variable sea surface roughness

In 2005 the Energy research Centre of the Netherlands (ECN) published its first version of the Offshore Wind Atlas of the Dutch part of the North Sea [3]. This version has been updated and improved using longer time series and another approach for the calculation of the roughness of the sea surface. In contradiction to other Wind Atlases which...

Update Offshore Wind Atlas: Implementing a variable sea surface roughness

In 2005 the Energy research Centre of the Netherlands (ECN) published its first version of the Offshore Wind Atlas of the Dutch part of the North Sea [3]. This version has been updated and improved using longer time series and another approach for the calculation of the roughness of the sea surface. In contradiction to other Wind Atlases which...