During hot seasons the inlet temperature of Nitrogen increases, as a result compressor consumes more power for compressing a specific mass ratio of fluid and consequently total energy consumption of the compressor increases as well. In this research, a three stage centrifugal compressor with intercooler was modeled thermodynamically in order to decreases the energy consumption of the compressor...

screw compressors are used to produce the compressed air in the refineries. because of the frequent failures and high prices of these compressors, this research was done to determine the failure causes in one of these compressors. in this study and after about 603 working hours , female rotor compressor had been fractured. metallurgical and other experiments showed that the defect in cooling wa...

The increasing importance of Unicode for text files, for example with Java and in some modern operating systems, implies a possible doubling of data storage space and data transmission time, with a corresponding need for data compression. However it is not clear that data compressors designed for 8-bit byte data are well matched to 16-bit Unicode data. This paper investigates the compression of...

In many industries, reducing the size of compression system represents a significant goal for designers. fact, increasing power density compressor actually means lowering production costs. The chief purpose this study is to compare, in terms aerodynamic performances, centrifugal consisting an impeller and volute, innovative concept based on principle two successive impellers designed work count...

Large scale, high pressure ratio (PR) centrifugal compressors are commonly made up of a radial impeller with vaned diffuser. In research to date, the majority and design has focused on extending operating range or improving compressor efficiency. However, cost weight saving can be achieved by reducing dimensions. This is study diffuser concept aiming reduce overall dimensions without any sacrif...

An experimental rig has been built to test a horizontal scroll compressor and a reciprocating compressor of similar size and capacity. The compressors were tested with refrigerant.R404A operating at varying evaporator and condenser temperatures. The paper provides much needed information regarding the efficiency of the compressors operating under the same conditions with the same system paramet...

Centrifugal compressors are used in many applications, including automotive turbochargers. Surge is an instability that occurs at low mass flow rates often damaging. Even mild surge produces noise characteristics cause problems with customer acceptance. It therefore important to be able predict both and deep onset. In existing literature, models resulting cubic-shaped compressor have been devel...


 Recently,
 there
 has
 been
 a
 growing
 interest
 in
 queryable
 XML
 compressors,
 which
 can
 be
 used
 to
 query
 compressed
 data
 with
 minimal
 decompression,
 or
 even
without
 any
 decompression.
 At
 the
 same
 time,
 there
 are
 very
 few
 such
 projects,
 which
 have
 been
 made
 available
 for
 testing
 and
 comparisons.
In
this
paper,
we
report
our
current
work
on
two
novel
quer...

This paper proposes lossless image compressors that are simpler than existing ones and yet still work well. The compressors process images in raster-scan order, and to code a pixel first estimate that pixel’s value by using a linear function of already-coded pixels. Next the compressors estimate the uncertainty in the first estimate by using a nonlinear function of already-coded pixels. Finally...

In this chapter a general introduction of centrifugal compression systems is presented. The unstable surge phenomenon in compressors is discussed, as well as possible means to avoid or suppress this instability. From an assessment of the current state of the art in control-oriented modeling and identification, the research objectives are formulated. 1.1 General introduction The general topic of...