A one-dimensional Casimir piston for massless scalar fields obeying Dirichlet boundary conditions in high-dimensional spacetimes within the frame of Kaluza-Klein theory is analyzed. We derive and calculate the exact expression for the Casimir force on the piston. We also compute the Casimir force in the limit that one outer plate is moved to the extremely distant place to show that the reduced ...

We describe the external and internal hydrogen interaction on contacting surfaces in “cylinder–piston rings” friction coupling. Under influence of high temperatures pressure, oil combustion chamber at a temperature up to 1473 K decomposes forms small amounts water. External (H2) is subsequently formed. Hydrogen removal from piston rings reduces heterogeneity structure, residual stresses, uneven...

– An adiabatic piston, separating two granular gases prepared in the same macro-scopic state, is found to eventually collapse to one of the sides. This new instability is explained by a simple macroscopic theory which is furthermore in qualitative agreement with hard disk molecular dynamics. The problem of the so-called adiabatic piston was described in 1960 by Callen [1] and has received a lot...

We consider a massless scalar field obeying Dirichlet boundary conditions on the walls of a two-dimensional L×b rectangular box, divided by a movable partition (piston) into two boxes of dimensions a × b and (L − a) × b. We compute the Casimir force on the piston in the limit L → ∞. Regardless the value of a/b, the piston is attracted to the nearest end of the box. Asymptotic expressions for th...

In a compressor the existence of the clearance volume is inevitable, even rolling piston compressor is a kind of compact structure compressor, overflow is a method to decrease the effect of clearance volume. In this paper, the overflow design on a rolling piston rotary compressor is discussed, which uses the high-pressure gas in the clearance volume, and discuss its effect on the performance of...

This paper presents a small wide-band loudspeaker. Particular efforts have been made to reduce the nonlinearities of the loudspeaker as much as possible. The motor structure is completely ironless, the elastomer suspensions are replaced by ferrofluid seals and a monobloc carbon foam piston substitutes the traditional conic membrane. The circular radiating surface, which is flat, has a diameter ...