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Dont have?Is there a reason why Turkey's aircraft carrier doesn't have an angled runway?
Because we need to use the whole length of the ship to launch some of our planes as we will not have catapults on the first incarnation of the ship. We do have an angled runway but it is angled inwards not outwards.Is there a reason why Turkey's aircraft carrier doesn't have an angled runway?
See this and let's talk again:On the AC turbine propulsion:
A possible marine version of the upcoming Kaan engine will likely have more power than the GE LM2500 engines so a shift from 4 turbine engines to 2 turbines like the HMS QE2 can be possible given the amount of time there is to the building timeline of the MUG.
What do you mean, diesel versus turbine efficiency?See this and let's talk again:
View attachment 67649
SFOC curve of gas turbines is not linear, there is a reason why we have combined propulsion units instead of a single engine to do it all. To operate engines most efficiently at two desired RPM and power output. At cruise speed (maximum range) 2 50 MW GT would consume more than 4 25 MW (according to the given graph) thus lowering the available range.What do you mean, diesel versus turbine efficiency?
Turbines work with their best efficiency between 90% and 100+% throttle but for some reason the UK went for a twin RR engine. Probably because it is UK made instead of American. Same applies to us if we can have our own engines we can mix and match as we wish. Smaller engines with large engines and diesel with turbine. We need to make marine diesel engines for whips as well. There was an initiative about it which we haven't heard about in years.SFOC curve of gas turbines is not linear, there is a reason why we have combined propulsion units instead of a single engine to do it all. To operate engines most efficiently at two desired RPM and power output. At cruise speed (maximum range) 2 50 MW GT would consume more than 4 25 MW (according to the given graph) thus lowering the available range.
There is also LM6000 (however i doubt if it is for military use) and Navies would have opted for this if they needed less engines.
It has 2 x GT, 4 x DE and IEP, none of these are driving propellers mechanically.Turbines work with their best efficiency between 90% and 100+% but for some reason the UK went for a twin RR engine. Probably because it is UK made instead of American. Same applies to us if we can have our own engines we can mix and match as we wish. Smaller engines with large engines and diesel with turbine. We need to make marine diesel engines for whips as well. There was an initiative about it which we haven't heard about in years.
And I believe we will possibly see CODELAG / COGELAD (some refers to as CODLAG) propulsion system as the design evolves, definitely not IEP but semi-IEP with generators either spared for propulsion or to supply electric generation. This eases exhaust funnel design as well, and provides safer propulsion (with diesels-only) at certain geographic areas of interest.It has 2 x GT, 4 x DE and IEP, none of these are driving propellers mechanically.
They better make something good.And I believe we will possibly see CODELAG / COGELAD (some refers to as CODLAG) propulsion system as the design evolves, definitely not IEP but semi-IEP with generators either spared for propulsion or to supply electric generation. This eases exhaust funnel design as well, and provides safer propulsion (with diesels-only) at certain geographic areas of interest.
Battery is simply ineffective for ship propulsion (too much space for too little propulsion - minimum 20 MW of electric motor will be needed on each propeller, do the computation from there), its best use could be for EMALS if they ever implement it. The cause of conversion will be separating funnels of generators and direct propulsion units and easing IR management and cooling systems. Collecting all the funnels and air intakes at one spot first increases IR greatly and complicates the deck arrangement. The ship will require enormous amount of generator.They better make something good.
If there is battery power in the propulsion system this can also be used for powering DC electric powered magnetic catapults among other things. I would suggest exploring the possibility of explosive powered and compressed air powered catapult systems as an alternative. Not that I have seen examples of them but those systems can remedy the lack of electric powered catapults and maybe even outperform them.
For propulsion battery maybe under-powered but considering all the onboard systems they will have to accommodate some battery capacity I guess. EMALS is pretty much the way to go as we have a number of different unmanned systems that can benefit from them. Below are some but there must be more coming in many different sizes over time. While many carrier borne planes weigh 25 to 30 tons our intended planes are much lighter so it shouldn't be too hard to make a catapult system even in time for initial commissioning of the ship.Battery is simply ineffective for ship propulsion (too much space for too little propulsion - minimum 20 MW of electric motor will be needed on each propeller, do the computation from there), its best use could be for EMALS if they ever implement it. The cause of conversion will be separating funnels of generators and direct propulsion units and easing IR management and cooling systems. Collecting all the funnels and air intakes at one spot first increases IR greatly and complicates the deck arrangement. The ship will require enormous amount of generator.
Batteries can't power EMALS. You need supercapacitors for that.They better make something good.
If there is battery power in the propulsion system this can also be used for powering DC electric powered magnetic catapults among other things. I would suggest exploring the possibility of explosive powered and compressed air powered catapult systems as an alternative. Not that I have seen examples of them but those systems can remedy the lack of electric powered catapults and maybe even outperform them.
Supercapacitor batteries then.Batteries can't power EMALS. You need supercapacitors for that.
Actually:Supercapacitor batteries then.
Technically a battery is a batch of cells that carry charge, so.
Q: What’s the power-supply chain look like?
A: The pulse-power and overall energy needs of the linear motor are well beyond what batteries or a conventional generator could deliver. Instead, the power produced by the generators is stored kinetically in rotors spinning at 6,400 rpm. To launch, this rotor-based kinetic energy is drawn off and converted to electrical power in a two- to three-second pulse. As the kinetic energy is drawn from the rotors, they slow down and their remaining available energy drops. The generator needs 45 seconds between launches to “recharge” the rotors by spinning them back up to capacity, ready to deliver another burst of power.
OK I know that part, I did my refresher reading yesterday but that is only the American way. Americans are using an alternating current system while Chinese are making a direct current system which can safely be assumed to be using supercapacitors or a combination of supercapacitors and chemical batteries. EMALS can launch up to 45.000 kg, way above what we initially want for our ship. The Chinese way is more suitable for our low power needs. It would be ideal to use magnetic catapults given that acceptable recharge times are achieved. However there could probably be other ways to achieve faster cycle times like compressed air or compressed gas as well.Actually:
Americans have been working on this for longer than Chinese (and we do not know of their R&D stage), they have fielded it while Chinese are still on trials. We will see which one works better.OK I know that part, I did my refresher reading yesterday but that is only the American way. Americans are using an alternating current system while Chinese are making a direct current system which can safely be assumed to be using supercapacitors or a combination of supercapacitors and chemical batteries. EMALS can launch up to 45.000 kg, way above what we initially want for our ship. The Chinese way is more suitable for our low power needs. It would be ideal to use magnetic catapult given that acceptable recharge times are achieved. However there could probably be other ways to achieve faster cycle times like compressed air or compressed gas as well.
Americans are expecting to get to their targeted failure rates and overall maturity of their system by 2030.Americans have been working on this for longer than Chinese (and we do not know of their R&D stage), they have fielded it while Chinese are still on trials. We will see which one works better.