Results Post Processing using MSC Acumen Francis BARREAU

Results Post Processing using MSC. Acumen Francis BARREAU - Snecma Moteurs Antoine SOEIRO - MSC. Software

Acumen Résultats • It is an application developed by MSC. Software for Snecma Moteurs. • It is developed using MSC. Acumen. • It allows post processing of the results calculated by Samcef (main mechanical analysis program at Snecma Moteurs).

Why Acumen Résultats ? • Post processing with Patran : – is adapted for all type of results, – allows a great variety of displays. • But : – It remains complicated to use, especially for an inexperienced user. – It is not easy to automate some displays. – It is missing some essential functions like units management. – It allows to obtain different values depending on the options chosen. Which value is the right one ?

Why Acumen Résultats ? • Acumen Résultats allows : – To display results calculated with Samcef. – Simplification of post processing tasks by offering an easy-tounderstand Graphic user interface even for an inexperienced user. – Display of results in a reliable manner : to get only the right values. – Automatic chaining of different Patran commands to get a complex display. – Automation of some post processing. – Addition of some missing functions (managing units) or improvement of existing ones ( titles, XY plots).

Acumen Résultats menus Main buttons. The different steps of post processing. Selection area. Input area. To go to the next or the previous step. Icons box.

Step 1 : to get the finite element model. • • “Wizard” like user interface. Acumen start. User identification. Selection of the MSC. Patran database. Finite element model definition. Immediate start of post processing or loading of Samcef Results. Other choices : – – Units used for calculation. Units for display. Language for the titles. Make use of the HTML report.

Steps 2 and 3 : utilities functions. • Step 2 : managing the model. – Managing groups and lists to display results on a part of the model. – Managing the coordinate systems used to display results. – Managing the viewport. • Step 3 : managing results. – To rename or delete existing results. – To create new results by linear combination. – To create new results by calculating the maximum, the minimum, the average of a set of existing results.

Step 4 : displaying results. To guide the user in order to get the display.

Step 4 : displaying results. • Only to allow options that correspond to the finite element model, the result quantity and the display. Examples : – To display 2 D tensors only for 2 D models. – To display a deformed plot only for displacement results. To display a vector plot for all types of vector results (displacement, loads, … ). – To display the results on the top, middle and bottom surface only for shell models.

Step 4 : displaying results. • To automatically select the Samcef result “code” number which correspond to the result quantity to display. Example : – – – ð Shell model. Stress display. Average stress at the center of the elements. Top surface stresses. Von Mises stresses. Result « Code number » Samcef : 3431.

Step 4 : displaying results. • To propose simple choices for the element results display : – To display the average value at the center of the elements. – To display an extrapolated value at the element nodes : • With discontinuities at the nodes. • With an average at the nodes. • With the largest difference of the values at the same node : this will help the user to check the quality of his calculation. • Example : for the average value at the center of the elements : MSC. Patran / Results equivalent options :

Step 4 : displaying results. • To merge a set of different Patran commands into one Acumen display. Examples : – Image captures with an automatic switch between black and white background colors. – XY Plots with automatic scaling and titles. – Stress tensors having traction values with a red arrow and compression values with a blue arrow.

Step 4 : XY plots • • • Automatic titles. Element, component, local coordinate system used. Automatic axis title : result displayed, units. Automatic axis scales with “whole” values. Automatic curve color and style.

Step 4 : tensor display. • Patran : – – – – – Results : Create / Marker / Tensor. Results : Select Result Case(s). Results : Select Tensor Result : « Code 3411 » . Results : Show As : « Principal » . Results : Show as Spectrum : Create : 3 colors : black, red, blue. Results : Show Tensor Box : scale = 0. 0. Results ; No tensor Label Results : Average Domain : None. Results Average Method : Average / Derive. Results : Extrapolation : Shape fn. Results : Apply. Ranges : create : 2 values. Ranges : Fit results and Calculate. Ranges : From/To : 0. 0 for intermediate values. Ranges : Apply. Ranges : Assign Target Range to Viewport. Set Range : don ’t overwrite range values. Results : Apply. • Acumen résultats : – – – – Spatial post processing. Result selection. Stress display. On 2 D elements. Average stress at the center of elements. Tensor display. Display options : no label.

Step 4 : displaying results. • To display results in reliable manner : to show only the relevant values. • Example : fringe plots of von Mises stresses at the center of the elements. Maximum value displayed : – Patran : • 2 « codes résultats » Samcef available (3411 ou 3310) x 2 « Averaging Domain » ( « None » ou « All » ) : at least 4 different maximum values can be displayed. – Acumen Résultats: • Automatic selection of Samcef « result code » 3411 and automatic choice of the display options : one maximum value is displayed in accordance with Snecma Moteurs’ post processing methods.

Step 5 : reproducing results. • To automatically reproduce the current display on other results : – Superimposed plots of deformation and stress fringe. – Image and animation capture. • To repeat the current display with different result units or title language. • To insert the current display into an HTLM report.

Step 5 : reproducing results. • • Example : modal calculation with stresses. Goal : to display the deformation and the von Mises stress fringe for all the modes and to capture all these images. • First part : step 4 : create this display for the first mode. • Second part : step 5 : reproduce this display : – – – Possible change of the units. Select the modes to display. Validate : Acumen does the plot and capture for all the selected modes.

HTML report. • • • Description of the model. Description of all the modifications of the results. Automatic insertion of all the graphic outputs.

Conclusion • MSC. Acumen has allowed us to create a new application for post processing Samcef results. • At least, 95% of Snecma Moteurs’ needs are fulfilled. • Post processing is now simpler, more reliable and can be automated. • A new application for defining Element properties, loads and boundary conditions for Samcef calculations is being developed by Snecma Moteurs and MSC. Software.