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First session#

The first time EnSim starts it opens an example project, a small kerolox sounding rocket, so that every page has something to show.

The Engine page after a run

Engine page. Inputs on the left, results on the right, the navigation rail at the far left.

The layout#

  • Navigation rail. Five pages: Engine, Vehicle, Flight, Analysis and Log. Ctrl+1 to Ctrl+5 jump between them.
  • Inputs. Each page keeps its own inputs on the left. Values are stored in the project as soon as you leave a field.
  • Run. The orange button at the bottom of the inputs, or F5, runs the page's main calculation. Esc cancels whatever is running.
  • Header. Project name, a one-line summary of the last engine result and how long it took.
  • Status line. Messages, and a thin progress line while something runs.

Calculations never block the window: you can switch pages, resize, or start something else while a Monte Carlo study is running.

Five minutes with the example#

  1. On Engine, press F5. The metrics fill in and the plots show pressure, temperature and Mach number along the wall contour.
  2. Change Chamber pressure to 30 bar and run again. Analysis → Compare can pin both results side by side.
  3. Open Vehicle. The drawing shows the centre of gravity with full and empty tanks and the centre of pressure. A static margin between 1 and 2 calibres is a comfortable target.
  4. Open Flight and press F5. With the example's 4 m/s westerly wind the rocket weathercocks to the west on the way up and drifts back east under its parachutes.
  5. In Flight → Dispersion, run 100 cases to see where the rocket might land.

Units and appearance#

View switches between SI and US customary units, and between the dark and light palettes. Values in the project are always stored in SI, so switching units never changes a design. View → Reduce motion turns off the short transitions.

Files#

Projects are .ensim files (plain JSON, see project files). File → Export report writes a Markdown summary; Export results as JSON writes every number the session computed. Right-click any plot to save it as PNG or SVG, or to export its data as CSV.