Refrigeration engineering and technology

4 - 8

Authors: O.V. Olshevska

Heat transfer and air flow aerodynamic characteristics in the microchannel condenser are examined in the paper. These characteristics were calculated in a wide range of air velocities for a particular model of heat exchanger.

16 - 23

Authors: S.V. Gayduk

The article describes the method of creating a cyclic-scheme decision of heat-using compressor refrigerating machine with carbon dioxide as the working substance, based on the thermodynamic analysis of the «method of cycles». The method of creating of the cyclic-scheme decision of the heat-using compressor machinery with carbon dioxide is based on the thermodynamic analysis of the "method of cycles". Through a phased build-up of irreversible in the cycle - sample (consistent «deterioration» of the ideal cycle) caused by the actual conditions of each element work in the composition of the refrigeration machine, reference cycles of valid machines were formed. Based on analysis, minimum elemental composition was defined, which provided real processes of heat transfer, expansion, compression in total with safe machine operation conditions with carbon dioxide. The estimation of the thermodynamic efficiency of cycles for real temperature machine operation modes was made.

32 - 36

Authors: P.A. Kotov

The analysis of the heat regeneration process in the Stirling engine is carried out. The impact of the regeneration on the performance coefficient and capacity of Stirling engine is considered.. How the thermal efficiency of the engine changes in the case of the nozzle design characteristics of the regenerator changing is shown.

44 - 52

Authors: V.L. Bondarenko; T.V. Diachenko; O.V. Diachenko

Designs of straight pipes flow condencers are investigated. The optimization results of devices on specific heat exchanger surface are shown. The energy analysis of reflux condensers for Ne-He mixture receiving is organized, the ways of their settlement are analysed. Methods of flow condensers (reflux condensers) constructive calculating is offered, the results are given and are compared with data, got under operating condition of industrial reflux condensers.

57 - 62

Authors: О.N. Shcherbakov

Procedure of experimental research of injection in the vaneless diffuser of centrifugal compressor is presented in the paper. The test rig, measuring system and calculation procedure are described.

68 - 75

Authors: М.S. Solodovnik

The paper presents analysis of the existing traditional methods of finding the best route for routing in networks. As an alternative to the traditional method, was proposed a neuro-fuzzy approach for the optimization of the routing process with the prediction of failure of the server's hard disk drive. For the prediction we used the package FuzzyTech environment Matlab. The program that is based on the unit neuro-fuzzy logic was written. The initial data are taken data corporation Google, which was published at a conference in Toronto. Based on these data, the predicted probability of failure of the hard disk server, resulting in changes in the architecture of a corporate network, and consequently bring changes in the routing process. Specific advantages of the neuro-fuzzy method over the traditional, namely, accounting expert opinion, the ability to self-learning and the ability to work with non-linear functions.