On page Dimensions, panel Shaft/ hub, the required shaft diameter is computed and the hub diameter is determined by the user.

¢ Shaft/Hub

 

 

The main dimensions of a designed impeller - suction diameter dS, impeller diameter d2, outlet width b2 - can be seen on Main dimensions panel. They can be recomputed by pressing the Calculate-button. The computation is based on "Euler's Equation of Turbomachinery", on the continuity equation and the relations for the velocity triangles as well as on the parameters and parameter ratios given in the tab sheets Design Point and Parameters.

 

You may accept the proposed values or you can modify them slightly, e.g. to meet a certain normalized diameter.

In case the checkbox Automatic is activated a new calculation will accomplished after any change of parameter. Then the manual alteration of the main dimensions is not possible.

 

Regarding the impeller size one should try to attain d2 values as low as possible. But there is a limit for a specified task: lower impeller diameters are leading to higher blade loading - up to blade angles β2 which may not be suitable anymore.

 

 

 

In the right panel of any tab sheet an information panel is situated, which holds the computed variables in accordance to the actual state of design, the resulting Meridional section as well as the Cordier-Diagramm with the location of the best point. These three sections can be chosen by the appropriate soft buttons in the heading.

 

 

In the Value section the following variables are displayed for information which result from calculated or determined main dimensions:

 

 

 

The Meridional section is based on the until now designed min dimensions.

 

 

 

The Cordier diagram is based on an intensive empirical analysis of proved turbomachinery using extensive experimental data.

 

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