Category: Chapter 3: Model Analysis in OpenVSP

Introduction

The VSPAERO Results Manager provides a convenient way to interact with and visualize VSPAERO solution data. Convergence histories for each case or condition may be examined either as the Log of the residual or as the actual value for many different metrics. The spanwise load distribution of a variety of results may be plotted collectively or on a per-case basis. If multiple cases were run, the sweep of these parameters may be plotted together by choosing any two variables from the menu. For example, a drag polar can be plotted by choosing CDtot as the X axis and CL as the Y axis. Any solution slices defined for a run may be visualized in the Cp Slice tab where the delta-Cp will be drawn for thin-surface VLM runs and Cp is drawn for thick-surface panel runs. Any unsteady VSPAERO cases, such as those for pitch response or rotating propeller blades, will have the time history of the results displayed in the Unsteady tab.

The previous results from a VSPAERO analysis may be loaded into the Results Manager without requiring a case restart by clicking the “Load Previous Results” button in the VSPAERO GUI. The Results Manager window will automatically display once a run is complete or results are loaded but may be manually launched by clicking the “Show Results Mgr” button. Each VSPAERO result output file is written to the relevant directory. However, if desired, users may save a collective results file by clicking “Export to *.csv” in the VSPAERO GUI.

Introduction

The VSPAERO Viewer provides visualizations of VSPAERO simulations for thin-surface, thick-surface, or hybrid cases. The Viewer features contours of pressure or vorticity, case legends, trailing wake visuals, and cut planes for volumetric flow properties among many other capabilities. This tutorial provides an overview of these capabilities and how to interact with the Viewer.

Introduction

The reference area and lengths for a VSPAERO case are defined under the Overview tab in the GUI. These values may be input manually or from any Wing component in the model. These reference values are used to nondimensionalize the aerodynamic loads from a VSPAERO run. Note that the reference span (bref) is used with the rolling and yawing moment coefficients (CMx and CMz) and the reference chord (cref) is used with the pitching moment coefficient (CMy).

Introduction

This tutorial provides a general overview of the VSPAERO GUI including the information and settings found within each tab. Case selection, flow conditions, and reference values are within the Overview tab while more advanced settings such as for propellers/rotors, stall estimation, wake behavior, and stability analyses are under the Advanced tab. The VSPAERO GUI also contains a terminal window which displays the solver status or “echo” of each run.