Super bummed! I thought I hit the jackpot with another TWO finds in one video, but the clips are such bad quality, are too short, and have a watermark over them. I found the short clips in the middle of a video about...you guessed it...the Los Alamos scientific laboratory, where they were explaining the uses of the facility's Cray-1 supercomputer.
Here's the video, with the computer graphics starting at 8:55:
Here are the graphics I've matched to Trek. The first was seen in both TMP and TWOK, and according to the video is a simulation of airflow in a tornado.
The second is a simulation of two nuclei colliding:
Some of the other simulations look like they may have also been used in the movies, but I've been unable to place any other ones.
I've futilty tried to find full, decent quality clips of those graphics based on what the video says they are, but I've had zero luck. I knew it had to run out sometime! I'm tempted to contact Los Alamos and ask them to send me all their vintage computer graphics...for, erm, education purposes