The joy of smoke and fire, from a test stand I helped analyze. J Below is a photo of a test of the gas generator off of a vintage F1 engine. There's more info and a video on the NASA website.
Below is a photo of the test stand being modified for the test, followed by a screenshot of the model. There isn’t much room to move around, with all of the piping systems twisting around the structure, test article, and each other.
Here is a section of the LOX system, followed by analysis of the new LOX support structure.