One of the topics we discussed on the Gaugeone3Dcircle weekly zoom call today was torpedo ventilators.
The outside is easy enough to model but we then realised we didn't actually know what the inside was like. One participant was able to say that he had once seen inside one and it wasn't as expected, but we also noticed they are not aligned along the carriage as theory expects. Google has not immediately yielded a picture of one in bits nor a drawing.
can anyone help?

The classic operation is supposedly that the torpedo is in line with the airflow ie along the carriage, and so the air flowing between the torpedo and the outer ring (rain guard) has to flow faster. Faster air is at lower pressure so then making holes in the torpedo in the middle should allow air to flow from the inside into this low pressure area. Simple.
But apparently not in practice.
Still need someone in a preserved railway repair shop to take one apart and be the first to post a picture on the internet. (or maybe ask a chatbot as they are in the news again today).

Well done finding the patent MG.

Another view of the underside 'pattress' here on the Altrincham group's restoration.
Perhaps the airflow side on to the torpedo produces low pressure above and below as with an aircraft wing and the slot described in the patent exploits that. The airflow due to the rainshield outer part though would make the currents complex.