The selection of lubricant is a key point in developing rotary compressor using R407C as a substitute for R22. The viscosity of oil, miscibility with refrigerant, thermal stability and compatibility with motor materials, etc, are all considerations. Furthermore, by reason of the POEs are more hygroscopic than mineral oils, hydrolytic stability and hygroscopicity of the selected oil must be cons...

Abstract: This paper is focused on the performance of centrifugal compressors for vehicle turbochargers operating at high altitude. The reasons for turbocharged diesel engine power loss increases and bad economy performance caused by exhaust gas energy utilization are investigated. The atmosphere’s impact on the turbocharger centrifugal compressor’s energy distribution characteristics under the...

Research on the various aspects of hermetic compressor design and development has been going on for a long period of time. As old questions get answered, new ones keep coming up. So much work has been done that a beginner in the compressor design field could easily get confused, and might not even know where to start. The purpose of this paper is to present a consolidated and simplified design ...

Flow losses through the valve ports contribute a significant portion to the total energy loss of a high speed compressor. As a result, in the energyconscious world of today, compressor designers are always busy finding methods and techniques to minimize these losses. It can be argued that the various fundamentally different compressor concepts would have different valve flow losses simply as a ...

This paper is intended as a review of the recent research and development of refrigeration and gas compressors in Japan. The review has been carried out by the papers as source material that are reported in the transactions, proceedings, and magazines in mechanical engineering field. Most compressor companies in Japan have long efforted to develop and apply advanced technology for innovative re...

The derivation of a compressor characteristic, and the experimental validation of a dynamic model for a variable speed centrifugal compressor using this characteristic, are presented. The dynamic compressor model of Fink et al. is used, and a variable speed compressor characteristic is derived by the use of energy transfer and loss analysis. It is demonstrated that taking into account the losse...

Until now the rotating and oscillating imbalance in the hermetic compressor has been balanced to and greater or lesser extent, but in addition internal springs were added where this was expedient from a design viewpoint. It is clear, however, that the position of the springs is an important factor in the transmitted vibrations. Generally, it proves in this paper that for a single-cylinder compr...

The primary goal of the work described in this paper was to evaluate and extend a virtual refrigerant charge sensor (VRC) for determining refrigerant charge for equipment having variable-speed compressors and fans. To evaluate the accuracy of the VRC, data were first collected from previous laboratory tests for different systems and over a wide range of operating conditions. In addition, new la...

Despite the generally accepted notion that geometric variability is undesirable in turbomachinery airfoils, little is known in detail about its impact on aerothermal compressor performance. In this work, statistical and probabilistic techniques were used to assess the impact of geometric and operating condition uncertainty on axial compressor performance. High-fidelity models of geometric varia...

The following paper describes the design and development issues with a variable capacity control 2-stage rolling piston compressor. The control mechanism was based on a gas-bypass control strategy. During the development, design issues surfaced that were not significant in the case of the full capacity version of the compressor. When the capacity was reduced, loss generation mechanisms remained...