Next Generation DDG and FFG thread (after 055, 052D, 054B)

[leibowitz]

Rumored 20,000-ton cruiser

What kind of increased munitions and sensor loadout could be done with the extra 8000 tons of displacement?

 

[tamsen_ikard]

What kind of increased munitions and sensor loadout could be done with the extra 8000 tons of displacement?

ship-launched df-26, hq-29, ship-launched drone perhaps

 

[Tomboy]

What kind of increased munitions and sensor loadout could be done with the extra 8000 tons of displacement?

Orca says it might be a Threatre BMD/Anti air cruiser, massive X-band or even MMW radar capable of accurately telling apart decoys from actual RVs/gliders and possibly direct energy weapons. Extra displacement for more VLS and potentially larger VLS for mid-course interceptors. 200-250MW total electrical capacity is within the expectations of such a cruiser.

 

[ACuriousPLAFan]

(Please note that all the power output values of gas turbine engines mentioned below are obtained at ISO conditions.)

For reference, the 055 DDGs (full-load displacement of ~13000 tons) are propelled by 4x CGT-25 marine gas turbine engines in COGAG configuration. Each CGT-25 engine has a power output of ~27 MW, meaning a combined power output of ~108 MW for propulsion.

In the meantime, as of today - China has successfully developed (or getting to the completion of developmental works) of more powerful marine gas turbine engines, namely the CGT-30, QC-400, CGT-40 and QC-500. There are also likely to be a CGT-50 and even a CGT-60, but due to the lack of more discernible information on these two marine gas turbine engines, they will be excluded from this discussion.

Comparing the propulsion configuration setting of the 055 DDGs with other settings using other marine gas turbine engines, assuming that all the gas turbine engines within their respective configuration settings are of the same model:

Gas Turbine Engine Model	Individual Power Output	Number of Gas Turbine Engines	Combined Gas Turbine Engine Power Output
CGT-25	~27 MW	4	~108 MW
CGT-30	~33 MW	4	~132 MW
QC400	~40 MW	4	~160 MW
CGT-40	~42 MW	4	~168 MW
QC500	~50 MW	4	~200 MW

In addition to the marine gas turbine engines, there is also the stated 10x diesel-electric engines, which together with the gas turbine engines, form the IEPS that is said to be capable of powering CVs (per SOYO) or CGs (per Cute Orca).

And when combining the above gas 4x turbine engines with the following 10x diesel-electric engines in IEPS configuration settings:

Gas Turbine Engine Model	Individual Diesel-Electric Engine Power Output	Number of Diesel-Electric Engines	Combined Diesel-Electric Engine Power Output	Combined IEPS Power Output
CGT-25	~3 MW to ~6 MW	10	~30 MW to ~60 MW	~138 MW to ~168 MW
CGT-30	~3 MW to ~6 MW	10	~30 MW to ~60 MW	~162 MW to ~192 MW
QC400	~3 MW to ~6 MW	10	~30 MW to ~60 MW	~190 MW to ~ 220 MW
CGT-40	~3 MW to ~6 MW	10	~30 MW to ~60 MW	~198 MW to ~228 MW
QC500	~3 MW to ~6 MW	10	~30 MW to ~60 MW	~230 MW to ~ 260 MW

Summing up, excluding the CGT-25-based setting - I do believe that both proposals by SOYO (meant for a CV) and Cute Orca (meant for a potentially BMD-capable CG) do have their respective merits, judging by the immense power output values where the above IEPS configuration settings are able to exert.

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However, it must be noted that the possibilities of the two pairs of gas turbine engines in the aforementioned IEPS configuration settings do not share the same power output should not be discarded (whereby one pair of gas turbine engines have higher/lower power output values than the other pair), for reasons such as (mainly) fuel-economy measures. With this in mind, the combined IEPS power outputs of such configuration settings would lie somewhere between the 4x CGT-25-based IEPS configuration setting and the 4x QC500-based IEPS configuration setting.

Orca says it might be a Threatre BMD/Anti air cruiser, massive X-band or even MMW radar capable of accurately telling apart decoys from actual RVs/gliders and possibly direct energy weapons. Extra displacement for more VLS and potentially larger VLS for mid-course interceptors. 200-250MW total electrical capacity is within the expectations of such a cruiser.

For reference: The Kirov-class CGN with a standard displacement of ~24000 tons and a l full-load displacement of ~28000 tons has a combined propulsion power of ~102 MW from its 2x nuclear reactors and 2x boilers, alongside the electrical power generation capability of ~18 MW from its 8x steam and gas turbine generators for shipboard hotel load.

Unfortunately, the power values for propulsion and electricity generation for the CG(X) is rather hard to come by, given how the program was cancelled before any final design has been formulated. However, from what we do know, the CG(X) has displacements ranging from ~20000 tons to ~25000 tons. Propulsion-wise, both conventional and nuclear-powered options were considered for the CG(X), with preference slanted for the latter. On the other hand, the hotel load power requirements of the CG(X) due to its expected role and responsibility are expected to be immense, including Theater Ballistic Missile Defense radars for BMD roles which is stated to consume ~31 MW.

Though, for the CG(X), since Cute Orca is about to write an article on the subject matter after the 9-3 parade (and the article is likely to be limited to paid readers/followers, sadly), hopefully there are people who can share what he wrote here.

So I suppose it depends on what kind of radar, sensor, computing and weapon systems and platforms that the purported CG is meant to field.

 

[Tomboy]

For reference: The Kirov-class CGN with a standard displacement of ~24000 tons and a l full-load displacement of ~28000 tons has a combined propulsion power of ~102 MW from its 2x nuclear reactors and 2x boilers, alongside the electrical power generation capability of ~18 MW from its 8x steam and gas turbine generators for shipboard hotel load.

Unfortunately, the power values for propulsion and electricity generation for the CG(X) is rather hard to come by, given how the program was cancelled before any final design has been formulated. However, from what we do know, the CG(X) has displacements ranging from ~20000 tons to ~25000 tons. Propulsion-wise, both conventional and nuclear-powered options were considered for the CG(X), with preference slanted for the latter. On the other hand, the hotel load power requirements of the CG(X) due to its expected role and responsibility are expected to be immense, including Theater Ballistic Missile Defense radars for BMD roles which is stated to consume ~31 MW.

Though, for the CG(X), since Cute Orca is about to write an article on the subject matter after the 9-3 parade (and the article is likely to be limited to paid readers/followers, sadly), hopefully there are people who can share what he wrote here.

So I suppose it depends on what kind of radar, sensor, computing and weapon systems and platforms that the purported CG is meant to field.

He did mention the original CG(X) proposal's electrical capacity as being "lackluster" in his original reply.

 

[taxiya]

Ok, your right but you also forgot that you could simply run a single turbine at high capacity to get around half power with diesels which according to you is what ships run at 80 percent of the time. Single large turbine do in fact have better efficiency than smaller turbines running at similar load, CGT25 only have a maximum efficiency of 36 percent while even the CGT30 improves this to 39.3 percent with larger models like CGT40 reaching 40+ percent. So, with two turbines you lose some power granularity since you'll lose the efficiency peak at 1/4 turbine power but I'm not so sure if ships often need that power level since for anything like low level cruise etc they could run on pure diesel with a IEPS design.

You still don't get the idea of granularity. I suggest you read the two papers that I provided. There is a dedicated thread for marine propulsion, it would be helpful if you surf through it.

 

[AndrewS]

On the other hand, the hotel load power requirements of the CG(X) due to its expected role and responsibility are expected to be immense, including Theater Ballistic Missile Defense radars for BMD roles which is stated to consume ~31 MW.

If we look at the Type-55, it has 6 x 5MW diesels to produce electricity.

So if we have 10 diesels, logically that implies at least 50MW of electricity generation. There's no point in going with a smaller sized diesel.

So that would match up with an additional 31MW requirement for a Theatre BMD radar (X-Band?)

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Another thought. With that much power, it would have a greater detection range against stealth aircraft and also be able to provide a weapons grade track for CEC.

Just for comparison, an E-7 has 300KW available. So 31MW implies 3.2x greater detection and targeting range.

 

[ACuriousPLAFan]

He did mention the original CG(X) proposal's electrical capacity as being "lackluster" in his original reply.

If we look at the Type-55, it has 6 x 5MW diesels to produce electricity.

So if we have 10 diesels, logically that implies at least 50MW of electricity generation.

So that would match up with an additional 31MW requirement for a Theatre BMD radar (X-Band?)

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Another thought. With that much power, it would have a greater detection range against stealth aircraft and also be able to provide a weapons grade track for CEC.

Just for comparison, an E-7 has 300KW available

Hence, if the aforementioned propulsion configuration setting is indeed meant for a CG, then it'd be really intriguing to see what sort of fuel-guzzling systems and equipment are getting fielded by said CG.

 

[AndrewS]

Chinese (conventional) Kirov here we come? 055 is already 13,000 tons, and seeing how usually warship classes gradually increase in size, it's not unreasonable to expect a 055 successor to be anywhere from 15,000 to even 20,000 tons.

Is it going to be a successor class to the Type-055? Or will it complement the existing force structure and sit above the the Type-055.

After all, you would only need 1-2 such ships in any surface group, given a Theatre BMD or anti-stealth radar role.

 

[AndrewS]

Hence, if the aforementioned propulsion configuration setting is indeed meant for a CG, then it'd be really intriguing to see what sort of fuel-guzzling systems and equipment are getting fielded by said CG.

The setup just looks weird for a carrier.

For a carrier, propulsion is what drives the power requirement. So it's either barely any power required or everything to operate at maximum speed. For a conventional carrier, fuel and endurance is a big issue. So operating radars with significant electricity and fuel consumption is best avoided.

So 6-8 gas turbines plus 2-6 diesels would be a better setup. Assuming that the same size diesels and gas turbines are used.