Compressors aspect ratio

The axial-flow compressors in aero gas turbines are heavily loaded. The aspect ratio of the blades, especially the first few stages, can be as high as 4.0, and the effect of streamline curvature is substantial. The streamline configuration is a function of the annular passage area, the camber and thickness distribution of the blade, and the flow angles at the inlet and outlet of the blades. The... 

Pressure Drop, Mass and Heat Transfer Pressure drop is more important in reactor design than in analysis or simulation. The size of the compressor is dictated by pressure drop across the reactor, especially in the case of gas recycle. Compressor costs can be significant and can influence the aspect ratio of a packed or trickle bed reactor. Pressure drop correlations often may depend on the geometry, the scale, and the fluids used in data generation. Prior to using literature correlations, it often is advisable to validate the correlation with measurements on a similar system at a relevant scale. 

The first step in the dimensioning process is to choose the mixture ratio jx. For the compressor type, which is not considered here, we choose fx = 3.0, i.e., fii, = 9.1 kg/s. Next we have to decide D, the diameter of the tube, i.e., we need a criterion for the choice of velocity of air. A crucial aspect which affects the choice of velocity is the wearing of the tube the higher the velocity is the greater is the wear. On the other hand, the velocity cannot be too low because of the risk of pluming (the velocity difference v - c has to be positive in all parts of the piping). Here we choose = 50 m/s with =1.2 kg/m. This gives D = 0.44 m. 

Also this aspect is closely examined in Chap. 4 and in case studies of Chaps. 6 and 7, but it is anticipated here by the analysis of data reported in Fig. 3.9, where the ratio between the power absorbed by the air compressor used for the tests of Fig. 3.8 and the power supplied by the stack is plotted versus the power supplied by the fuel cell system (FCS power). The results show that an acceptable... 

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