Overview
Every component of an hydraulic system has physical dimensions and other properties that influence its hydraulic behaviour. When you draw an object on the ARTS design sheet you are essentially creating a virtual version of a real world object. For example, once you draw a pipe on the screen you can then display its properties. Every hydraulic object that is placed on the design sheet has properties associated with it. These properties are accessible via dialog boxes known as Property Pages. If you look at the ARTS property pages of a pipe, you will find that the pipe has a length and a diameter associated with it, as well as other parameters relevant to its hydraulic performance. The same holds true for all other objects. Thus, the system drawn on the design sheet is not just a bare graphic, such as a similar image drawn on paper, but is backed up by a full complement of parameter values. These values can be readily edited, thereby replacing the initial values with actual values of the pipe you are modelling.

Pipe property pages

Property pages come replete with graphic images, object shape options (circular or rectangular sedimentation tank, channel shape, etc.), editable initial parameter values, and, most importantly, a comprehensive computational capability related to the internal hydraulic behaviour of the object. Property pages also include scaled interactive graphics and tooltips which display the range within a particular parameter can be changed, providing a quicker, easier and more accurate method of data entry. The object's full range of properties pages can be accessed by clicking the tabs located at the top of the properties page. The tab order generally reflects the required sequence of data input by the user.

Typical examples of object property pages are shown above and below:

Pump property pages

It will be noted that the Head property page for a pump (above) is in the form of a graph of head (H) as a function of flow (Q). This curve is generated by ARTS from the H/Q values entered for three points on the curve. The user selects each point, in turn, edits its values and then clicks on the Recalculate Curve button; ARTS replots the H/Q curve. The Power and NPSH characteristic curves for pumps are entered in the same manner.

The use of the property page technique for data input simplifies the process and makes it more reliable and less time-consuming. With this method, it is very easy to evaluate the influence of each parameter on the hydraulic behaviour under evaluation. The user simply edits a single parameter value and re-runs the analysis. For example, if it required to determine the influence of varying pump speed on the performance of a booster pump in a pipe network, the user has only to edit the pump speed value on the main property page for the pump and then re-run the analysis.