Avaliação dos modelos semi-empíricos do TOOLKIT ASHRAE para compressores centrífugos e turbinas

Abstract

This work deals with the turbochargers modeling, allowing analysis of mass flow rate and efficiency characteristic for application in refrigeration field. The based model used is the semi-empirical proposed by document ASHRAE -T.C. 4.7 document. The behavior of the ASHRAE model for radial turbines and centrifugai compressors was observed. Results of simulation using ASHRAE model are compared with data obtained from Brazilian manufacturer. In order to improve results, modifications are implemented, mainly in the way parameters used by models are obtained, as well as corrections are suggested taking in to account, compressible effects and losses model, considering that turbo machine fluid flow behave similar to flow in pipes. Results obtained showed improvements in model response, specifically with turbines, however for centrifugai compressor model difficulties were encountered due to lack of data and problems in parameters Identification, even though this work shows improves in compressor model response, especially at high mass flow rates.