The concept of a smart skin embodies the philosophy of a multilayer structure that includes sensing elements, actuation elements and a controller. Such an embedded system has been developed for under water vehicle applications where the objective is the control of both near and far field noise. Acoustic/structural characterization is a necessary part of optimal design, however the simulation mo...

Reciprocating compressors of the crosshead design have sealing elements around the piston and piston rod. These seals can be of lubricated or nonlubricated design. This paper will give details about our R&D-work for dry running piston rod sealings or packings for high pressure applications. Starting with an overview of packing design some details are given about tribological tests. Measurements...

The design and dynamic characterization of a free piston compressor is presented in this paper. The free piston compressor is a proposed device that utilizes combustion to compress air into a high-pressure supply tank. The device is configured such that the transduction from thermal energy to stored energy, in the form of compressed gas, is efficient relative to other small-scale portable power...

PISTON is a machine independent software framework for developing scientiic applications on parallel computers. It presents a consistent data-parallel distributed memory model across a wide range of architectures. It has been implemented on the Fujitsu AP1000 as well as on SIMD and SMP machines. This paper brieey describes the implementation of PISTON on the AP1000 and presents timing results a...

A piston motion controller for a free-piston internal combustion engine is presented. To improve dynamic performance in the control of the piston motion and engine compression ratio, the controller response is determined from a prediction of engine top dead centre error rather than the measured value from the previous cycle. The proposed control approach showed superior performance compared wit...

Experiments have been performed to assess the utility of unsteady one-dimensional heat conduction modelling for the calculation of heat losses during a free piston compression process. Heat transfer measurements have been obtained within a gun tunnel barrel using surface junction thermocouple instrumentation. The gun tunnel was operated with a relatively heavy piston such that the shock waves i...

A method of transferring an RF reference frequency through the turbulent atmosphere is presented. Using two optical wavelengths close to each other can compensate for the influence of the atmospheric piston error. The influence of the atmosphere on the phase of the optical signal is calculated together with the remaining error by transferring two carriers. The system was implemented in a labora...

We report results of molecular dynamics simulation of shock wave propagation in silicon in [100], [110], and [111] directions obtained using a classical environment-dependent interatomic potential (EDIP). Several regimes of materials response are classified as a function of shock wave intensity using the calculated shock Hugoniot. Shock wave structure in [100] and [111] directions exhibit usual...

We study the dynamics of three elastic particles in a finite interval where two light particles are separated by a heavy "piston." The piston undergoes surprisingly complex motion that is oscillatory at short time scales but seemingly chaotic at longer scales. The piston also makes long-duration excursions close to the ends of the interval that stem from the breakdown of energy equipartition. M...