This paper reviews the design of a combination variable I fixed-step port unloader system for moderate capacity refrigeration screw compressors. The general specification of an unloader system to meet application requirements and specific issues of port and flowpath design are discussed. The paper demonstrates use of a comprehensive compressor simulation and a commercial pipe flow analysis prog...

A model of a flat triple pendulum with obstacles imposed on its position is used for the modelling of a piston-connecting rod-crankshaft system of a mono-cylinder four-stroke combustion engine. The introduced selfexcited system can be only treated as the first step in more advanced modelling of real processes, but some examples of numerical simulations exhibit well known six stages of the pisto...

We study the dynamics of three particles in a finite interval, in which two light particles are separated by a heavy "piston," with elastic collisions between particles but inelastic collisions between the light particles and the interval ends. A symmetry breaking occurs in which the piston migrates near one end of the interval and performs small-amplitude periodic oscillations on a logarithmic...

In a wet clutch system, a piston is used to compress the friction disks to close the clutch. The position and the velocity of the piston are the key effectors for achieving a good engagement performance. In a real setup, it is impossible to measure these variables. In this paper, we use transmission torque and slip to approximate the piston velocity and position information. By using this infor...

We are developing a technique to measure segment misalignment of large telescopes based on wavefront estimation using phase-diverse (inand out-of-focus) images. We report the current results of an experiment to measure piston errors on the Keck II primary segmented mirror, through atmospheric turbulence, using phase-diverse phase retrieval. The segment piston errorss are separated from the rand...

We study a heavy piston that separates finitely many ideal gas particles moving inside the unit interval. Using averaging techniques, we prove precise rates of convergence of the actual motions of the piston to its averaged behavior. The convergence is uniform over all initial conditions in a compact set. The results extend earlier work by Sinai and Neishtadt, who determined that the averaged b...

we compare two approaches for a markovian model in flexible manufacturing systems (fmss) using monte carlo simulation. the model which is a development of fazlollahtabar and saidi-mehrabad (2013), considers two features of automated flexible manufacturing systems equipped with automated guided vehicle (agv) namely, the reliability of machines and the reliability of agvs in a multiple agv jobsho...

This paper introduces the high efficiency of a horizontal rolling piston type compressor for household refrigerators. In the rolling piston type compressor, excessive compression loss and leakage loss largely affects the efficiency of the compressor. An experimental analysis of the following three items was made to determine that the performance characteristics of the compressor could be improv...

We continue the study of the time evolution of a system consisting of a piston in a cubical container of large size L filled with an ideal gas. The piston has mass M ’ L and undergoes elastic collisions with N ’ L gas particles of mass m. In a previous paper, Lebowitz et al. (1) considered a scaling regime, with time and space scaled by L, in which they argued heuristically that the motion of t...