We present preliminary results from two computational magnetohydrodynamic (MHD) studies of magnetic nozzles. The first study models the magnetic nozzle expansion of a plasma into a near vacuum with a resistive MHD solver. Results from resistive MHD simulations suggest that further model development is necessary to replicate experimental results within the desired physical regime. The second stu...

This paper presents the design and characterization of micro-fabricated 0.5 MHz silicon-based ultrasonic nozzles. Each nozzle is made of a piezoelectric drive section and a silicon-resonator consisting of five Fourier horns, each with half wavelength design and twice amplitude magnification. Results of impedance analysis and measurement of longitudinal vibration confirmed the simulation results...

Flow in a generic ventral nozzle system was studied experimentally and analytically with a block version of the PARC3D computational fluid dynamics program (a full Navier-Stokes equation solver) in order to evaluate the program's ability to predict system performance and internal flow patterns. For the experimental work a one-thirdsize model tailpipe with a single large rectangular ventral nozz...

Under the three breakup regimes, the jet surface waves of different nozzles are captured and measured. The nozzles have different length to diameter ratios and contraction angles. The measured wavelengths are compared with the reported conclusions which were obtained by using spatial and temporal linear stability analysis. The results show that the jet wavelengths of different breakup regimes a...

The advantages of using multi-head gantry machines in printed circuit board assembly are flexibility and efficiency combined with a relatively low acquisition price. However, the practical efficiency of this machine type depends on several difficult decisions that have to be made by a machine operator. In this paper two basic problems that have a significant effect on the use of a gantry machin...

Title of Document: Analysis of the Initial Spray from Canonical Fire Suppression Nozzles Ning Ren, Master of Science, 2007 Directed By: Professor André Marshall, Department of Fire Protection Engineering The performance of a fire suppression spray is governed by injector discharge characteristics. An atomization model based on the theoretical evolution of a radially expanding sheet generated by...

The formulation and validation of a novel quasi-one-dimensional particle-in-cell code for the simulation of magnetic nozzles is presented. Quasi-one-dimensional effects are included through virtual displacements of magnetized particles from the axis of symmetry and cross-sectional area variation according to preservation of magnetic flux. A modified, semi-implicit Boris algorithm is developed f...