Hot stuff stays where it’s needed at Seawork

If you look closely, you will see that the two coloured sections have an unusual ceramic coating. Developed by Zircotec, the coating keeps the heat (even on an ‘ordinary’ turbocharger) very localised.

Matt Waterman of Turbo Dynamics explained that this localisation of heat helps everything run smoothly. ‘It means, for one, that the thermal energy from the turbocharger remains associated with that section, instead of heating the surrounding area, such as the intake on the engine itself.’

He added that since the engine input can do with a relatively low air temperature, making it as dense and oxygen rich as possible, stray heat from the other end of the turbocharger can really stress the both the engine coolers and intercoolers.

He also said that since the turbocharger uses the energy from the exhaust gases, you need to keep these gasses hot for efficiency’s sake. By maintaining this temperature, which can be around 700° C, you increase the drive on the exhaust wheel, and there’s less energy lost through heat dissipation. This means the whole turbo doesn’t need to work as hard, which again helps it maintain its reliability.

‘The drop between the two needs to be quite phenomenal, since one end runs best at 700° to 800° C, while the other end, which is after all usually only about a foot away, is best kept at something under 100°, said Mr Waterman. ‘Even a relatively small difference, such as 20°, will make a change to the efficiency of the engine.’

There is also the safety element. While merely touching a turbocharger casing might well result in a very serious injury, this coating reduces such an incident to the level of nasty, but not dramatic. As Mr Waterman said, ‘You can brush against it without cooking yourself, although I still wouldn’t recommend leaning on it!’

This benefit of keeping the heat where it’s needed can be applied to most turbochargers, not just the large frame Garrett GT42 model, and might well find applications on other equipment where temperatures need to be kept localised. Given the colouring possibilities, there may well be a new trend that sees the addition of interesting and aesthetically pleasing pipework displayed onboard commercial craft as well as Seawork display stands. Turbo Dynamics will be on the one numbered 158 at Seawork 2010.