Blast off with a revolutionary feature, Rotational Acceleration!

The success of rotating hydraulic systems could revolve around the methods employed, make sure to use only the best when modeling such a system. As the surge of space travel innovation continues, safety always comes to mind.  All too often the hazards of traveling through the colloquial final frontier prove the necessity of double checking calculations and the validity of the adage, units kill.  With the large number of piping networks that can rotate around an axis in the absence of the earth’s typical gravitational pull rotating objects involved in space flight, these systems are no exception to the hard-learned lessons to date.

Rotating hydraulic systems present a unique modeling challenge that must be addressed. It’s a topic that holds everything together when considering the momentum equation, and that is gravity. In the hydrostatic portion of any quality momentum balance, the gravitational impact is considered by the acceleration parameter. Typical piping systems are usually present in Earth’s gravity so this acceleration is well known. However, in the cold reaches of space, this is frequently not the case. As mentioned previously, every detail can count when dealing with mission critical design. So, suppose that a compressible piping system on the surface of a rotating object that has a cylindrical shape must be validated with a hydraulic model. Would your hydraulic modeling tool be able to accurately represent this system with a model? If you are using AFT Arrow, the answer is yes!

As a matured leading software, AFT Arrow attracts some of the biggest names in the aerospace industry for not only its usability, but also the quality nature of the analysis it provides. The Rotational Acceleration feature is one such facet that helps cater to this pioneer-prone science. When the feature is active, centripetal forces can be accounted for in the form of a more accurate hydrostatic calculation. This feature addressed the previously mentioned challenge of what value to use for the acceleration constant. With the required rotational speed input, users are provided with results reflecting the true impact of their system’s operating conditions.

The feature works by using the elevations (still required) throughout the model to calculate an acceleration constant used in hydrostatic pressure results. The elevations would now represent a distance from the axis of rotation. An example being, a junction inlet elevation of one foot is representative of that junction inlet one foot away from the axis of rotation. Increasing elevations effectively increases this distance. As such, it is possible to accurately model pipes with varying acceleration constants for their respective ends.

The feature is very simple to turn on by navigating to the System Properties window of your AFT Arrow model and browsing to the System Data tab. Figure 1 below shows the feature turned on and a specified rotational speed. Note, that while the feature is active the gravitational acceleration is not and cannot be used in tandem with the rotational setting.

Figure 1 Rotational Acceleration feature active

Rotating satellites, although perhaps the easiest example to visualize, are not the only instance that a compressible system may be rotating. One other example would be a rotating component of a turbomachinery configuration. Regardless of the need, safety will remain a staple in any project. AFT Arrow can clearly help provide the most accurate model possible in this regard.