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I am looking for a range of temperature of the exhaust stubs of a turboprop engine, typically a P&W one.

However, I am not able to find such information on P&W's technical documentations available on the internet. On this stackexchange, the closer topic I coud find was that one on the EGT range of a jet engine. I would expect a temperature around 500 - 600 °C, but I am not sure about it.

Many thanks in advance for any information you would have. Cheers!

KrKAlex
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1 Answers1

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The P&W PT6, which is probably the most common turboprop/turboshaft engine in the world, has a maximum continuous EGT of ~600°C and maximum instantaneous of 760°C.

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(source: EASA)
(note: the respective document for a regular PT6 doesn't list the EGT, but only the inter-turbine temperature, ITT, which is generally used to manage the PT6 engine. Since the PT6T has the same parts, just twice, the same ITT will result in the same EGT.)

Since EGT is the terminal temperature, after all the turbine stages, it's not going to drop much while going into the exhaust. Plus, consider a slight permitted overtemperature.

Generally, if you're installing it in your plane, it's best to use materials that can handle at least 760°C for 30 seconds (where the engine might still remain in the B-area, safe to fly after inspection) and 650°C continuously (might be pushed there in a OEI contingency), with 550-600°C typical service.

This is still titanium range, but calling for high-temperature alloys such as 1100, rather than basic structural Ti-6Al-4V. Any factory exhaust will be designed for appropriate temperature.

Therac
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  • Thank you for your reply. Yes, a PT6 is the most widespread so this was the one I was thinking about. Many thanks for sharing the EASA document, this is exactly the type of information I was looking for. Now it's time for me to run my simulation! Also, sorry I cannot upvote your reply since I do not have enough reputation ... but it really helped me. – KrKAlex May 09 '23 at 10:55
  • @KrKAlex There's the tick mark below the answer - you'll start building up your rep after clicking it. Happy to be of help. – Therac May 09 '23 at 11:35
  • the ITT limit is the same, and so should be the EGT sounds confusing, you could rephrase to explain the ITT (also explain what ITT means; Inter-Turbine Temperature) is a measure for the EGT, the only thing is that a turbine is in between the ITT and the EGT, so the ITT is higher than the EGT. – 0scar May 10 '23 at 10:34
  • @0scar, in my case I am interested in the EGT. I consider EGT as the temperature of the air at the exit of the exhaust stubs. Therefore, I assume it is significantly lower than the ITT. – KrKAlex May 10 '23 at 11:52
  • @KrKAlex Yes, the ITT is up to 1090°C. Same for PT6 and PT6T (dual installation). ITT and EGT correlate almost perfectly, except for low-speed turbine wear, which gradually increases the EGT. The PT6 engine is thermally limited at the ITT stage, so EGT is more of an informational point. – Therac May 10 '23 at 19:18
  • @Therac Thank you for the explanation, once again. – KrKAlex May 11 '23 at 06:44