A hybrid keyboard-guitar interface using capacitive touch sensing and physical modeling

This paper was presented at the 9th Sound and Music Computing Conference, Copenhagen, Denmark.This paper presents a hybrid interface based on a touch- sensing keyboard which gives detailed expressive control over a physically-modeled guitar. Physical modeling al- lows realistic guitar synthesis incorporating many expres- sive dimensions commonly employed by guitarists, includ- ing pluck strength and location, plectrum type, hand damp- ing and string bending. Often, when a physical model is used in performance, most control dimensions go unused when the interface fails to provide a way to intuitively con- trol them. Techniques as foundational as strumming lack a natural analog on the MIDI keyboard, and few digital controllers provide the independent control of pitch, vol- ume and timbre that even novice guitarists achieve. Our interface combines gestural aspects of keyboard and guitar playing. Most dimensions of guitar technique are control- lable polyphonically, some of them continuously within each note. Mappings are evaluated in a user study of key- boardists and guitarists, and the results demonstrate its playa- bility by performers of both instruments

Calibration of lubrication force measurements by lattice Boltzmann simulations

This paper was presented at the 2nd Micro and Nano Flows Conference (MNF2009), which was held at Brunel University, West London, UK. The conference was organised by Brunel University and supported by the Institution of Mechanical Engineers, IPEM, the Italian Union of Thermofluid dynamics, the Process Intensification Network, HEXAG - the Heat Exchange Action Group and the Institute of Mathematics and its Applications.Many experiments explore the hydrodynamic boundary of a surface by approaching a colloidal sphere and measuring the occurring lubrication force. However, in this case many different parameters like wettability and surface roughness influence the result. In the experiment these cannot be separated easily. For a deeper understanding of such surface effects a tool is required that predicts the influence of different surface properties. Here computer simulations can help. In this paper we present lattice Boltzmann simulations of a sphere submerged in a Newtonian liquid and show that our method is able to reproduce the theoretical predictions. In order to provide high precision simulation results the influence of finite size effects has to be controlled. We study the influence of the required system size and resolution of the sphere and demonstrate that already moderate computing ressources allow to keep the error below 1%.This study is funded by DFG priority program SPP 1164

Eccentric Taylor-Couette Flow with orbital motion of the inner cylinder

This paper was presented at the 3rd Micro and Nano Flows Conference (MNF2011), which was held at the Makedonia Palace Hotel, Thessaloniki in Greece. The conference was organised by Brunel University and supported by the Italian Union of Thermofluiddynamics, Aristotle University of Thessaloniki, University of Thessaly, IPEM, the Process Intensification Network, the Institution of Mechanical Engineers, the Heat Transfer Society, HEXAG - the Heat Exchange Action Group, and the Energy Institute.The flow in a Taylor-Couette system is one of the most explored flows today. The behaviour of the flow is characterized by Reynolds number, radii and aspect ratio. By reducing the gap width the Taylor-Couette system can be used as a simplified bearing model which has one additional feature. To cover flow effects of a real bearing the rotating inner cylinder moves on an offset track. Thus the system is also characterized by a varying annulus. That changes the eccentricity which is also related to the critical Reynolds number for the system. There is a higher Reynolds number for a higher eccentricity. This is used as a benchmark to validate the code. Depending on the eccentric position of the rotating inner cylinder one can notice either Taylor Vortex flow or Couette Flow. After testing the code the gap width will be adjusted to realistic bearing geometries. This second part refers to bearing simulations where the gap width is adjusted to real bearing conditions. In Fact the present system is a simplified bearing, which covers not all details of a real one. It becomes more complex in later stages of the project, where oil feedings and notches are implemented as well as the occurrence of cavitation. Furthermore the offset tracks will be much more complex. The final goal is to develop a 3D simulation tool for hydrodynamic journal bearings that resolves effects like cross flow from the oil feedings and also cavitation. Known methods based on the Reynolds equations fail to predict important flow characteristics in complex bearing geometries due to their two dimensional nature. If sufficiently low local pressure areas occur, cavitation- related damages may appear. So the pressure distribution of the flow is of interest

Microcirculatory blood flow: Functional implications of a complex fluid

This paper was presented at the 3rd Micro and Nano Flows Conference (MNF2011), which was held at the Makedonia Palace Hotel, Thessaloniki in Greece. The conference was organised by Brunel University and supported by the Italian Union of Thermofluiddynamics, Aristotle University of Thessaloniki, University of Thessaly, IPEM, the Process Intensification Network, the Institution of Mechanical Engineers, the Heat Transfer Society, HEXAG - the Heat Exchange Action Group, and the Energy Institute

Prediction and evolution of drop-size distribution of an ultrasonic vibrating microchannel

This paper was presented at the 2nd Micro and Nano Flows Conference (MNF2009), which was held at Brunel University, West London, UK. The conference was organised by Brunel University and supported by the Institution of Mechanical Engineers, IPEM, the Italian Union of Thermofluid dynamics, the Process Intensification Network, HEXAG - the Heat Exchange Action Group and the Institute of Mathematics and its Applications.We report in this paper the evolution of a physically-based drop size-distribution coupling the Maximum Entropy Formalism and the Monte Carlo method to solve the distribution equation of a spray. The atomization is performed by a new Spray On Demand (SOD) device which exploits ultrasonic generation via a Faraday instability. The Modified Hamilton’s principle is used to describe the fluid structure/interaction with a vibrating micro-channel conveying fluid excited by a pointwise piezoactuator. We combine to the fluid/structure description a physically based approach for predicting the drop-size distribution within the framework of the Maximum Entropy Formalism (MEF) using conservation laws of energy and mass coupling with the three-parameter generalized Gamma distribution. The prediction and experimental validation of the drop size distribution of a new Spray On Demand print-head is performed. The dynamic model is shown to be sensitive to operating conditions, design parameter and physico-chemical properties of the fluid and its prediction capability is good. We also report on a model allowing the evolution of drop sizedistribution. Deriving the discrete and continuous population balance equation, the Mass Flow Algorithm is formulated taking into account interactions between droplets via coalescence. After proposing a kernel for coalescence, we solve the time dependent drop size distribution using a Monte Carlo Method which is shown to be convergent. The drops size distribution upon time shows the effect of spray droplets coalescence

Flow and particle deposition using an integrated CFD model of the respiratory system

This paper was presented at the 3rd Micro and Nano Flows Conference (MNF2011), which was held at the Makedonia Palace Hotel, Thessaloniki in Greece. The conference was organised by Brunel University and supported by the Italian Union of Thermofluiddynamics, Aristotle University of Thessaloniki, University of Thessaly, IPEM, the Process Intensification Network, the Institution of Mechanical Engineers, the Heat Transfer Society, HEXAG - the Heat Exchange Action Group, and the Energy Institute.In the present study a theoretical investigation on flow, particle motion, and deposition in the respiratory system is reported. An integrated computational model of the respiratory system is developed comprised of nine sequential computational blocks corresponding to the nasal cavity, the pharyngo-trachea, and a series of branches of the pulmonary system. Airflow during steady-state inhalation inside the human respiratory system was determined using computational fluid dynamics (CFD) for inlet velocities, vin = 1-20 m/s, corresponding to inhalation flow rates of 9 to 180 L/min, and particle deposition was examined in detail for particle sizes, D=1-20μm. Local deposition efficiencies as well as spatial distribution of deposited particles were found to be strongly dependent on the particle size and volumetric flow rate

Control of convection by dfferent buoyancy forces

This paper was presented at the 3rd Micro and Nano Flows Conference (MNF2011), which was held at the Makedonia Palace Hotel, Thessaloniki in Greece. The conference was organised by Brunel University and supported by the Italian Union of Thermofluiddynamics, Aristotle University of Thessaloniki, University of Thessaly, IPEM, the Process Intensification Network, the Institution of Mechanical Engineers, the Heat Transfer Society, HEXAG - the Heat Exchange Action Group, and the Energy Institute.Thermal convection in vertical concentric cylinders under the influence of di erent buoyancy force fields is the focus of the experimental project ’CiC’(Convection in Cylinders). The objectives are to investigate thermal convective flow in natural gravity with axial buoyancy and in micro-gravity environment of a parabolic flight with radial buoyancy, and additionally also the superposition of both buoyancy force fields. The radial buoyancy is forced by the dielectrophoretic effect due to applying a high-voltage potential Vapp between the two cylinders. The experiment contains two separately fully automated experiment cells, which differ only in their radius ratio η = b/a. The convective flow is observed with tracer particles and laser light sheet illumination. For the case of natural convection, there exists a stable single convective cell over the whole Rayleigh number domain with Ra ~ ΔT with increasing the temperature difference between the inner and outer cylindrical boundaries. For the case of a pure dielectrophoretic driven convection in micro-gravity environment, stratification effects are described with RaE ~ Vapp with increasing the high voltage potential. The superposition of both buoyancy forces indicates the disturbance of the single convective cell and therewith the onset of instabilities at very low Ra for the smaller η. The presented results demonstrate that the dielectrophoretic effect can be used for flow control and enhancement of heat transfer applications in space as well as on Earth.The “Convection in Cylinders (CiC)” project is funded by the German Aerospace Center DLR within the “GeoFlow” project (grant no. 50 WM 0122 and 50 WM 0822). The authors would also like to thank ESA (grant no. AO-99-049) for funding “GeoFlow” and the “GeoFlow” Topical Team (grant no. 18950/05/NL/VJ)

An experimental study on heat transfer and pressure drop of MTHE

This paper was presented at the 3rd Micro and Nano Flows Conference (MNF2011), which was held at the Makedonia Palace Hotel, Thessaloniki in Greece. The conference was organised by Brunel University and supported by the Italian Union of Thermofluiddynamics, Aristotle University of Thessaloniki, University of Thessaly, IPEM, the Process Intensification Network, the Institution of Mechanical Engineers, the Heat Transfer Society, HEXAG - the Heat Exchange Action Group, and the Energy Institute.A micro-sized shell and tube heat exchanger (MTHE) was fabricated, and its performance in heat transfer and pressure drop was experimentally studied. The single-phase forced convection heat transfer correlation in the tube side of the MTHE was proposed and compared with previous experimental data in the Reynolds number range of 500-1800. The averaged deviation of the correlation in calculating the Nusselt numbers is about 6.59%. The entrance effect in the thermal developing region was discussed in detail. In the same range of Reynolds number the pressure drop and friction coefficients were found to be considerably higher than those predicted by the conventional correlations. The product of friction factor and Reynolds number is also a constant, but about one fold higher than the conventional. The reasons resulting in these physical phenomena have been preliminary discussed.Tianjin Science and Technology Committee Key Project fund, under Grant No. 08JCZDC203

Off-plane motion of an oblate capsule in a simple shear flow

This paper was presented at the 4th Micro and Nano Flows Conference (MNF2014), which was held at University College, London, UK. The conference was organised by Brunel University and supported by the Italian Union of Thermofluiddynamics, IPEM, the Process Intensification Network, the Institution of Mechanical Engineers, the Heat Transfer Society, HEXAG - the Heat Exchange Action Group, and the Energy Institute, ASME Press, LCN London Centre for Nanotechnology, UCL University College London, UCL Engineering, the International NanoScience Community, www.nanopaprika.eu.We investigate the mechanical equilibrium state of an oblate capsule when its revolution axis is initially off the shear plane. We consider an oblate capsule with an aspect ratio of 0.5 and a strain-hardening membrane. The three-dimensional fluid-structure interaction problem is solved numerically by coupling a finite element method with a boundary integral method. The capsule converges towards the same mechanical equilibrium state whatever the initial orientation. This equilibrium depends on the capillary number Ca, which compares the viscous to the elastic forces and on the viscosity ratio between the internal and external fluids. For = 1, the tumbling and swinging motions, observed when the revolution axis is initially in the shear plane, are mechanically stable until Ca 1; when Ca is further increased, the capsule assumes the rolling motion that is observed when its revolution axis is initially aligned with the vorticity axis. When is increased, the tumbling-to-swinging transition appears for higher Ca and the swinging-to-rolling transition for lower Ca. For 5, the swinging regime completely disappears: depending on Ca, it is then either the tumbling or the rolling motion that is the mechanical equilibrium state

Numerical Simulation of Microflows with Moment Method

This paper was presented at the 4th Micro and Nano Flows Conference (MNF2014), which was held at University College, London, UK. The conference was organised by Brunel University and supported by the Italian Union of Thermofluiddynamics, IPEM, the Process Intensification Network, the Institution of Mechanical Engineers, the Heat Transfer Society, HEXAG - the Heat Exchange Action Group, and the Energy Institute, ASME Press, LCN London Centre for Nanotechnology, UCL University College London, UCL Engineering, the International NanoScience Community, www.nanopaprika.eu.A series of hyperbolic moment equations is derived for the Boltzmann equation with ES-BGK collision term. These systems can be obtained through a slight modification in the deduction of Grad’s moment equations, and such a method is suitable for deriving systems with moments up to any order. The systems are equipped with proper wall boundary conditions so that the number of equations in the boundary conditions is consistent with the hyperbolic structure of the moment system. Our numerical scheme for solving the hyperbolic moment systems is of second order, and a special mapping method is introduced so that the numerical efficiency is highly enhanced. Our numerical results are validated by comparison with the DSMC results. Through the numerical solutions of systems with increasing number of moments, the convergence of the moment method is clearly observed