Boiling in a tube bundle

Boiling in a tube bundle

Research and Development… they’re the same thing, aren’t they? Well, no.

Research is about investigating nature by thinking up and actually doing experiments (disproving and improving theories). You can’t plan scientific research any farther than the next experiment. Werner Von Braun said research was what he was doing when he didn’t know what he was doing.

Development (a.k.a. Technology, Engineering) is about applying research results in a highly controlled way to deliver some benefit to people.

Anyway, this image is of an experiment designed to discover what happens within an industrial boiler. It was the subject of my Ph.D. Thesis, which answered the question, open since before the Rainhill Trials in 1829, about which arrangement of tubes provides the most effective heat transfer to the fluid. Despite the industrial flavour of the work, it was definitely scientific research.

It turns out that there is very little difference between an array of tubes arranged as shown and rotational variants of that configuration.

The mundane issue of cleaning the tube bundle dominates in practice…vertical ‘lanes’ between tubes are easier to clean and are therefore preferred, since heat transfer performance is so dependent on surface condition.

(See P.R. Andrews and K. Cornwell, “Cross-sectional and longitudinal heat transfer variations in a tube bundle section”, Chem. Eng. Res. Des., 65, 127-130, 1987).