How JAXA, the Japan Aerospace Exploration Agency, Designed their Rocket Engine Turbopump?

At the present time, Stepanoff’s design methodology based on empiricism using an experimental database is still widely used in pump design.

This design is so popular because based on his experimental investigation of the correlations between many design parameters and pump performance he “strongly suggested” that the optimum blade exit angle was 2β = 22.5 degrees. It is true that designers using Stepanoff’s method can design pumps that demonstrate moderate performance with very cheap design costs.

These facts along with a rich experimental database make this method attractive as a standard design methodology. However, it is also true that Stepanoff’s method can not be applied to breakthrough designs beyond the design range he originally tested.

LE-7 LOX turbopump

“TURBOdesign1 is an intelligent design tool, which gives us fresh insight into the fluid dynamics of the flow through the pump stage”.