Talk:Closed-cycle gas turbine

Comparison to Stirling engine

Isn't this just a modified Stirling engine? Dennis Brown (talk) 16:30, 7 December 2011 (UTC)

AFAIK, no; the Stirling doesn't use a turbine and then there's the matter of Stirling cycle vs Brayton cycle. -- Limulus (talk) 19:21, 7 December 2011 (UTC)

Then I will need to read up a bit, as I'm confused as to how a closed system can use the Brayton Cycle. I'm no expert, but I thought the Brayton cycle required burning fuel between the compression section and turbine, ie: being necessarily an open system. I know there is the Ericsson Cycle and other closed heat engines, but just not familiar with this one. Dennis Brown (talk) 20:44, 7 December 2011 (UTC).

Apparenly not; the refs I'm finding (e.g. [1]) say that Brayton can be open or closed, it's just that open is much more common in usage. -- Limulus (talk) 22:51, 7 December 2011 (UTC)

Another ref: [2] "Thermodynamic analysis of a closed-cycle, Brayton gas-turbine plant with a heat exchanger powered by the sun has been studied. A Brayton cycle is simpler than a Rankine cycle and has an advantage in places where water is scarce and expensive." Also this one: "helium gas turbines have been extensively investigated for reactor applications, particularly with respect to achieving high efficiency in electricity generation based on a closed Brayton cycle as a replacement for the conventional steam Rankine cycle." -- Limulus (talk) 01:24, 8 December 2011 (UTC)

Why are normal steam turbines excluded ?

Why are normal steam turbines excluded ? Is it because there is a phase change (to water) in part of the cycle ? - Rod57 (talk) 13:05, 9 July 2019 (UTC)

Why are these considered for nuclear power plants and not for coal/oil/gas power plants ?

Why are these considered for nuclear power plants and not for coal/oil/gas power plants ? Is it to do with the temperatures, pressures, or something else ? - Rod57 (talk) 13:17, 9 July 2019 (UTC)

in nuclear power plants you have the issue that you cannot produce steam at arbitrary temperatures as you can with combustion. So if you run a gaseous coolant like helium through the core (to avoid the critical temperature of water as would be the working temperature in a supercritical water reactor), it makes sense to run it thru a gas turbine. If you burn a chemical fuel (coal, gas, oil, hydrogen...) you can cool it with water and heat that to whichever temperature your material survives... Hobbitschuster (talk) 13:01, 18 April 2022 (UTC)

Working fluid = primary coolant?

So in - for example - a helium cooled reactor using a closed cycle gas turbine, would the helium that flows thru the core be the one that drives the turbine or would there be a heat exchanger between the two? In the former case, would it be a "combined cycle" with a secondary water loop driving a steam turbine with the "waste heat" of the primary cycle? Hobbitschuster (talk) 13:03, 18 April 2022 (UTC)