Fluid materials can be referenced by the 1D flow tube Property or by the Convection loads.

Advanced fluid materials are used to define complex convection correlations. Access to this advanced convection correlation lib can be found under the MSC Sinda icon, located at the top right of Patran menu bar, or inside the convection load input forms. This convection correlation lib facilitates the use of both basic and advanced fluid materials.

The convection correlation lib includes one initial form and 44 convection correlation forms.

The initial form consists of 2 sub-forms: the correlations sub-form and the basic fluid sub-form. You can choose the correlations by clicking the icons on the correlation sub-form, or input the convection id, and then return. These icons are filtered by three switches (Internal, External, or Natural) and three toggles (Laminar, Turbulent, and Transitional). The basic fluid sub-form is used to create/edit basic fluid materials with correlation id = 0 or empty.

Each correlation form consists of a view sub-form and a variables sub-form. The view sub-form illustrates and describes the convection situation, and shows the formulas and notes/restrictions. The variable sub-form includes several data boxes for the correlation. The convection coefficient preview calculates the convection coefficient based on the parameters in the form. An additional pop-up window may be needed to input fluid temperature, time, wall temperature, or the gravitational constant. Each correlation corresponds to one type of advanced fluid material. You can view/edit this fluid material in Material/Create/Fluid by clicking the existing materials. The correlation variable sub-form contains a fluid material list box and the temperature or time (or both) dependent field list box. Clicking the basic fluid material in the list box will upload the basic material parameters into corresponding data boxes (except the mass flow rate and convection coefficient) but keep the correlation id and other correlation related parameters the same as before. Clicking the advanced fluid material in the list box will change/update the variables sub-form.

Clicking the browser button will switch back to the initial sub-form depending on which sub-form was last shown.

When the convection correlation lib is called from the convection loads, clicking the OK or Apply button uploads the newly created/edited fluid material into the load input form and into the fluid material list box. Please note: Inside fluid materials, only the convection coefficient is considered a load variable. Therefore, the convection coefficient inside the basic fluid material, or the convection coefficient calculated from advanced fluid material will be used, and the remaining parameters will be ignored. For a coupled advection load, the valid mass flow rate is from the fluid material referred by the 1D flow tube property, not from the material in the load input form. In MSC Sinda for Patran the convection coefficient is a load variable and mass flow rate is a material variable.

Depending on the convection correlation type, if temperature or time function is referred by some variables, the Convection Coefficient Preview button may open a new window that allows the user to fill in some temporary data and then calculate the Coefficient value. This is useful to see what value MSC Sinda will use before making the run, and helps the user to verify if they are using the correct correlation and fluid properties.