Dynamic Shaft Design

This program is used for the mechanical design of complex fluid mixer shafts. The program uses matrix math techniques to solve a set of partial differential equations that describe the rotating elements of a fluid mixer system. The user inputs a complete mathematical description of the shaft system along with the location of forces and masses as well as the shaft rotating speed. The program then solves the partial differential equations and gives outputs such as stress, bending moments, deflection and first and second critical speeds. This program is state of the art and can be used to analyze any fluid mixer rotating elements, no matter how large or how complicated. It can handle changes from solid to hollow shaft and back to solid. It can be used on systems with or without steady bearings and with or without steps (changes in diameter) in the rotating shaft system. The program can output the calculation results to an Excel spreadsheet where multiple analyses can be studied.

The attached screen shot shows the analysis of a mixer shaft that is 2 inches solid from the top bearing to the lowest impeller 148 inches below the upper bearing. The gearbox bearing spacing is 10 inches and there is a bearing in a mechanical seal cartridge 8 inches below the lower gearbox bearing. The upper impeller weighing 50 pounds is 90 inches below the seal bearing and the lower impeller weighing 50 pounds is 40 inches below the upper impeller. The first critical speed of this system is 102.7 rpm and the second critical speed is 745.0 rpm.