Entropy Production Analysis of Steam Ejector under Typical Working Conditions

The ejector widely used in the dead steam recovery process has the disadvantage of low efficiency. Reducing the entropy production rate of the ejector working process is of great significance to improve the efficiency. In this paper, the entropy production rate of steam ejector and the ratio of entropy production in each component are analyzed in typical working conditions. It is found that, under different design conditions, the influence of the entropy production rate of the ejector on the thermodynamic perfection is not consistent. For small expansion ratio and large compression ratio ejector, it is easier to improve the thermodynamic perfection by reducing the entropy production rate, while for the ejector with compression ratio less than 1.64, it is difficult by this way. For the ejectors with small expansion ratio and large compression ratio, the optimization should be carried out according to the priority by reducing the entropy production in the mixing chamber, the entropy production in the nozzle, the entropy production in the diffuser and the entropy production in the suction chamber, while the entropy production in the suction chamber can be reduced to a limited extent.