Comment by chaostaco

I'm no expert in this field, but my understanding is that it would occur in the concentrating vortex core. The orange part would become narrower and narrower (the OpenAI article says "like spaghetti"), and the velocity in that concentrating region would grow without bound as the finite blowup time is approached. The rendered flow never literally shows "infinity" because every snapshot before the blowup time is still finite.