Surge is one of the two main dynamic instabilities that can occur in compressor systems (the other is the rotating stall) preventing their satisfactory operation and being potential cause of serious damages. In this paper we consider a Close Coupled Valve (CCV) as actuator, and we suggest the use of a second-order sliding-mode (2-SM) technique for the active control of the surge phenomenon. We ...

per is concerned with the control of a three-stage compressor with upstream roots blower. Based on the detailed mathematical model derived in the first part of this contribution, a simplified model for controller design is developed in this part by exploiting the periodicity of the system variables of the piston compressor. Afterwards, a nonlinear multiva-riable control strategy is proposed for...

In this study we analyzed both bending and impact stress of the discharge valve of the rotary compressor using a commercial FEM program MSC/NASTRAN and predicted the amount of maximum stress and the location it occurred. We measured the maximum stress of the valve in bolt case compressor using the resistance type strain gages. Good agreement was made by the comparison between the numerical anal...

A horizontal hermetic scroll compressor has been developed for applications with high heatof-compression gases, including natural gas, air and helium (cryogenics). The compressor is a low profile horizontal design with oil-flooded cooling of the compression process. Combined with components required for oil separation and cooling, this design provides a smooth, continuous compression process fe...

In the design of the small hermetic compressor, the forces acting on the compressor shell are important parameters to study for noise and vibration control. However, the input forces to the shell cannot be measured directly. In this paper, random force spectra on compressor shell has been measured indirectly with in-situ · vibration responses and system information. Three existing techniques of...

This paper describes the concept and the design features of a new, oilfree, reciprocating high pressure compressor for technical gases. The compressor is unique in concept and design, and introduces various new design elements. A magnetic coupling makes the compressor hermetic and allows inlet pressures of up to 16 bar. A new kind of clearance seal in the high-pressure stages allows reliable oi...

The application of carbon dioxide as natural refrigerant in commercial refrigeration systems has attracted higher interest in recent years for its promising energy efficiency and ecological sustainability. This paper presented the development of a low side scroll compressor for the bottle cooler application in the trans-critical cycle. Experimental tests were performed in two different temperat...

Computer simulation of the thermodynamic cycle of the cylinder process of compressors providef' valuable information for compressor engineers. For example, the valve losses and the gas pulsation losses can be estimated from the simulation results. In general, the results of the computer simulation suggest that increasing the discharge port area always reduces the related valve loss and thus hel...

Tris paper, through analy3is to the specific power of the compressor, indicates that to reduce the power loss caused by friction is an important way to reduce the specific power of the compressor, investigates the realizability employing a single piston ring or a piston ring with small elasticity in the high speed double acting compressor, and raises a standpoint for a high speed double acting ...