Jan K. Spelt
University of Toronto
ParticleJet (fluid)Finite element methodBrittlenessComposite materialEpoxyMetallurgyMaterials scienceJoint (geology)AbrasiveStrain energy release rateFracture (geology)SolderingMachiningNozzleMechanicsFracture mechanicsStructural engineeringAdhesiveSurface finishStress (mechanics)
231Publications
48H-index
5,694Citations
Publications 198
Newest
#1Joshua Palumbo (U of T: University of Toronto)H-Index: 1
#2Maryam Navi (RyeU: Ryerson University)H-Index: 5
Last. Marcello Papini (RyeU: Ryerson University)H-Index: 40
view all 5 authors...
Inertial microfluidics has been used in recent years to separate particles by size, with most efforts focusing on spiral channels with rectangular cross sections. Typically, particles of different sizes have been separated by ensuring that they occupy different equilibrium positions near the inner wall. Trapezoidal cross sections have been shown to improve separation efficiency by entraining one size of particles in Dean vortices near the outer wall and inertially focusing larger particles near ...
1 CitationsSource
#1Joshua Palumbo (U of T: University of Toronto)H-Index: 1
#2Maryam Navi (RyeU: Ryerson University)H-Index: 5
Last. Marcello Papini (RyeU: Ryerson University)H-Index: 40
view all 5 authors...
Size-based particle separation using inertial microfluidics in spiral channels has been well studied over the past decade. Though these devices can effectively separate particles, they require a relatively large device footprint with a typical outer channel radius of approximately 15 mm. In this paper, we describe a microfluidic device with a footprint diameter of 5.5 mm, containing a helical channel capable of inertial particle separation fabricated using abrasive jet micromachining. The separa...
1 CitationsSource
#1Lucas da Silva Maciel (U of T: University of Toronto)H-Index: 3
#2Jan K. Spelt (U of T: University of Toronto)H-Index: 48
Abstract Discrete element methods (DEM) have been widely used in predicting the behavior of vibrated granular media, including that in vibratory finishing (VF) processes. In VF loose abrasive particles are fluidized by a vibrating container and the particle vibration work on the surface of parts entrained in the granular bed. In the present work, DEM was used to predict the forces exerted by the container walls on the granular media and the results were compared with previous experimental measur...
4 CitationsSource
#1Lucas da Silva Maciel (U of T: University of Toronto)H-Index: 3
#2Jan K. Spelt (U of T: University of Toronto)H-Index: 48
Abstract The bulk flow and local impact velocities of loose abrasive particles in vibratory finishing operations have been explained in the literature in terms of the forces exerted by the vibrating container walls. In the present work, these forces were measured using a force sensor embedded in the walls of a vibrating tub finisher loaded with various amounts of steel media and subject to different vibration frequencies. It was found that wall-media contact forces increased with the depth of me...
2 CitationsSource
#1Xiangyu Luo (U of T: University of Toronto)H-Index: 1
#2Joshua Palumbo (U of T: University of Toronto)H-Index: 1
Last. Jan K. Spelt (RyeU: Ryerson University)H-Index: 48
view all 4 authors...
Abstract To decrease the size of the eroded footprint resulting from abrasive air jet machining, the aerodynamic focusing of an abrasive particle jet was investigated. Using a slot nozzle abrasive jet, the best focusing employed a pair of bounding air jets tilted 60 ° to the abrasive jet, at an impingement height of approximately 10% of the standoff distance from the workpiece. An optimum bounding jet pressure existed to achieve the maximum focusing, resulting in a machined channel width reducti...
4 CitationsSource
#1Michael Teti (U of T: University of Toronto)H-Index: 2
#2Jan K. Spelt (RyeU: Ryerson University)H-Index: 48
Last. Marcello Papini (RyeU: Ryerson University)H-Index: 40
view all 3 authors...
Part I of this two-part paper presented mixing chamber conditions and jet characteristics in a high-pressure abrasive slurry jet micro-machining (HASJM) system. The present paper describes the modeling of the slurry entrainment process within the mixing chamber and mixing tube of the nozzle using computational fluid dynamics (CFD) and shows how the results can be used to explain and predict machining performance. The slurry flow rate into the mixing chamber was found to have a large impact on th...
4 CitationsSource
#1E. van Wijk (U of T: University of Toronto)
#2D.F. James (U of T: University of Toronto)H-Index: 2
Last. Jan K. Spelt (RyeU: Ryerson University)H-Index: 48
view all 4 authors...
The resolution of features machined with abrasive slurry jets is dependent on the diameter of the erosion footprint on the workpiece and on the stability of the jet. Previous work has shown that the footprint size decreases, but the jet oscillation increases, with increasing polymer concentration. The present study investigated the effect of nozzle design on jet stability in abrasive slurry-jet micro-machining of glass using slurries with dissolved polymers. A variety of transparent acrylic nozz...
Source
#1Ryan Brown (U of T: University of Toronto)H-Index: 2
#2Jaleel MoiduH-Index: 2
Last. Jan K. Spelt (U of T: University of Toronto)H-Index: 48
view all 4 authors...
Abstract This two-part paper presents measurements and modelling of creep deformation at relatively low stress of two epoxy adhesives used in opto-electronic applications, one having a relatively high modulus and the other a low modulus. Part I describes the bulk tensile creep tests at various temperatures (75–95 °C) and stress levels representative of those in opto-electronic devices. A novel laser-based method of non-contact creep strain measurement was used to eliminate errors associated with...
1 CitationsSource
#1Ryan Brown (U of T: University of Toronto)H-Index: 2
#2Jaleel MoiduH-Index: 2
Last. Jan K. Spelt (U of T: University of Toronto)H-Index: 48
view all 4 authors...
Abstract The creep deformation of two glass-epoxy adhesive joints, representative of joint designs used in opto-electronic devices, was measured at various temperatures and relatively low stress levels using a novel, ultra-sensitive method employing optical interference fringes. The adhesive creep models obtained in Part I were then used as the constitutive equations in finite element models of the joints with the objective of assessing the accuracy of the predictions of creep deformation at the...
1 CitationsSource
#1J. Schwartzentruber (RyeU: Ryerson University)H-Index: 5
#2Jan K. Spelt (RyeU: Ryerson University)H-Index: 48
Last. Marcello Papini (RyeU: Ryerson University)H-Index: 40
view all 3 authors...
Abstract Abrasive waterjet (AWJ) piercing of composite laminates typically generates interlaminar delamination due to the hydraulic shock (‘water hammer’) associated with liquid jet impact. This paper extends previous liquid jet impact literature by examining the effects of hydraulic shock on an anisotropic carbon-fiber/epoxy laminate using finite element analysis and experiments. A transient fluid-structure interaction model was developed to simulate the AWJ impact process, thereby providing a ...
19 CitationsSource