Like I said before, with these new higher power gas turbines and the higher power diesels as used in the latest Type 054B a Type 052 replacement cruiser with two diesels and two gas turbines would have similar displacement to the 10,000 ton Type 055.
Chinese Marine Propulsion
- Thread starter jobjed
- Start date
Yes, 2x 30MW-class or 2x 40MW-class gas turbines and 2x 7MW-class diesel engines for a 052D/DG-successor in a CODOG or CODLOG arrangement, and 2x 40MW-class gas turbines + 2x 25MW-class or even 2x 30MW-class gas turbines for a 055-successor in a COGAG or COGLAG arrangement.
My rather ambitious hopes will need to be based on more realistic grounds.
According to @勤劳朴实罗素里 on Weibo, the next-generation DDG class that come after the 055 is very likely to discard the COGAG system of the 055 DDG in favor of utilizing the CODLAG system.
That means instead of the 4x CGT-25M gas turbine engines for propulsion and 8x diesel engines for power generation on the 055 DDGs (1st illustration), the next-gen DDGs are very likely to be equipped with only 2x CGT-40M gas turbine engines and 2x 4-7MW diesel engines for propulsion, plus another 4-6x diesel engines for shipborne power generation (2nd illustration).
The main propulsion engines of the CODLAG system is also likely to have similar arrangements as those on the Arleigh Burkes (distributed alternatingly along the centerline), instead of the 055s (concentrated at amidships).
As for the IEP system - We may only see it on larger warships due to size and complexity concerns of DDGs (of which the 076 LHD might be the first in the PLAN to have IEP, although this remains speculation for the time being).
The 712th, 703rd and (the most recently, 3rd and 4th photos) 701st Institutes have published academic papers and patent applications on CODLAG propulsion systems.
In that case, I do hope that the next-generation DDG class which succeeds the 052D/DGs will also utilize the CODLAG system (and discards the CODOG system on the 052D/DGs), but this time with 2x CGT-30M gas turbine engines and 2x 4-7MW diesel engines for propulsion, plus 2-4x diesel engines for shipborne power generation.
Last edited:
Every system has its pluses and minuses. In the case of CODLAG the GTs are still not connected to the grid and cannot provide extra juice for power-hungry GaN radars, lasers, coil guns, HPMs, EA, and other fancy electronics. But it certainly would be a step up from the 055's current all-or-nothing COGAG where one lucky hit on the transmission will totally immobilize the ship.
In addition to your points:
CODLAG system also provides a healthy boost towards the warship's endurance, given that lower speed cruising (which is basically what DDGs typically spend significant amount of time doing while at sea) can be done with only *two 4MW electric motors that are powered by the 6-8x 6-7MW diesel engines*. When high-speed dash is needed, the two CGT-40M gas turbines would be used in addition to those two electric motors. This is a massive fuel saving when compared to only using the fuel-hungry gas turbine engines for propulsion on the 055 DDGs.
In fact, with each CGT-25M having an output of 24.3MW at navy conditions (at 25-27 °C with certain loss of exhaust, etc), the 055 DDG only requires two of its four CGT-25Ms to reach 28 knots (48.6MW), and three of its four CGT-25Ms to reach 30 knots (72.9MW), per table below. Simply put, the 055 DDGs have too much propulsion power.
Such speeds can be achieved with only two CGT-40Ms (38+MW x 2 = 76+MW at navy conditions) in addition to the two electric motors.
Moreover, the spaces freed up inside the warship's hull from the reduction of the number of larger-sized gas turbine engines onboard the warship can be utilized for more and/or larger diesel engines and power generators, thus allowing the greater amount of electrical power generation for the electric motors and ship-based facilities (radar and sensor systems, computing systems, weapon platforms, etc).
(** = Also as correction for my previous post, namely 2x electric motors and not 2x diesel engines.)
A few days ago, @勤劳朴实罗素里 on Weibo discussed about the future of marine propulsion systems on PLAN warships. I figured that it'd be great to share it here for referencing purposes.
Translated article below the horizontal line here. Note that the translation may not be 100% accurate.
Since the 12th Five-Year Plan (2011-2015) period, China has officially launched the research and development of a new generation of marine propulsion systems. By the end of the 14th Five-Year Plan (2021-2025) period, significant progress has been made in various systems, and it is expected that the next generation of surface ships will begin to be equipped with these systems starting in the 15th Five-Year Plan (2026-2030) period at the earliest.
The characteristics of the new generation of domestically developed marine propulsion systems can be summarized in six key aspects: "Integration" (联), "Electric" (电), "Large" (大), "Quiet" (静), "Mechanical" (机), and "Compact" (小). Here’s a detailed explanation of each key aspect:
1. Integration (联):
The new generation of propulsion systems mostly feature integrated power systems. These systems not only combine multiple engines of the same type but also achieve cross-type integration—combining diesel engines, electric motors and gas turbines. This includes both "soft integration" (such as diesel-electric, gas-electric and propulsion motor combinations) and "hard integration" (such as diesel engines, electric motors, gas turbines and gearbox combinations). Representative products have already been developed, such as diesel-electric-diesel systems (used in new law-enforcement vessels) and integrated power systems (e.g., the 076 LHD).
2. Electric (电):
The new generation of propulsion systems boasts enhanced power generation capabilities, providing stronger power supply to shipboard grids. For instance, integrated power systems can deliver 20 MW or more to the warship's grid. Hybrid systems like diesel-electric-diesel and diesel-electric-gas can also supply power to the grid via shaft-driven generators. The power output of domestically produced shaft-driven generators is expected to meet the maximum electrical load of medium-sized FFGs like the Type 054/054A, and they can be integrated with the warship's independent power generation units. This will significantly support the deployment of high-energy equipment and weapons.
3. Large (大):
The new generation of propulsion systems will utilize advanced indigenous power units capable of delivering higher single-shaft output power. By the end of the 14th Five-Year Plan period, the single-shaft output power of medium-sized DDGs and FFGs was 10-25 MW, while that of large DDGs was 48-49 MW. The next generation of domestic warships will be larger in scale, requiring more powerful propulsion systems. It is expected that medium-sized DDGs and FFGs will need single-shaft power of 16-32 MW, while large warships will require single-shaft power exceeding 40 MW.
4. Quiet (静):
Due to changes in maritime defense requirements, Chinese research institutes and departments have set high standards for the noise reduction capabilities of the new generation of propulsion systems. Whether it is electric propulsion, mechanical propulsion or hybrid systems, all must have enhanced vibration damping and noise reduction capabilities. Compared to the previous generations of propulsion systems, the new propulsion systems feature meticulous design improvements in sound insulation, vibration damping and internal transmission mechanisms, which will enhance the stealth and anti-submarine capabilities of next-generation warships.
5. Mechanical (机):
The new generation of propulsion systems will continue to widely use mechanical combined-gearboxes and will incorporate advanced gearbox sets in electric propulsion systems. Since ultra-high energy weapons are not yet ready for deployment, the power demand for next-generation medium-sized DDGs and FFGs will not exceed 16 MW. Existing advanced diesel-electric units can already meet this demand. Therefore, the next generation of medium-sized DDGs and FFGs, which will be produced in large numbers, will adopt lighter mechanical transmission/hybrid systems. These systems will use shaft-driven generators and advanced diesel-electric units to provide 12-16 MW of power (equivalent to 3-4 times the power generation on the 052D DDGs). To address the large size and weight of current propulsion motors, the next generation of electric propulsion systems will introduce high-speed motors and combined gearboxes. High-speed motors are smaller and lighter, and combined gearboxes will facilitate the transmission and integration of motors and propulsion shafts, further reducing the footprint of electric propulsion systems.
6. Compact (小):
Compared to the previous generation of propulsion systems, the new generation of propulsion systems will have higher power density and a smaller footprint for the same power output, freeing up more internal space on warships. For example, the 052D DDG currently uses a combined diesel and gas (CODAG) propulsion system with four diesel-electric units (two forward and two aft), with a total power output of approximately 57 MW at maximum capacity. If upgraded to a diesel-electric-gas integrated system, the total power output could reach 72 MW, representing a 24% increase in available propulsion power and a 360% increase in power generation capacity. At the same time, the number of intake and exhaust ducts would be reduced by two, and the volume of the smokestack could be reduced by 15% or more. The transmission mechanisms of the new systems are designed with high compactness in mind, improving their adaptability and benefiting medium and light surface ships. With the introduction of high-speed motors and combined gearboxes, the overall volume of electric propulsion systems will be significantly reduced, making them suitable for small and medium-sized unmanned vessels and enhancing their overall performance.
Additionally, some specialized ships will still use cross-type alternating propulsion systems. These systems are typically custom-designed based on the ship's mission requirements and are not widely applicable, so they will not be discussed further here.
Translated article below the horizontal line here. Note that the translation may not be 100% accurate.
Since the 12th Five-Year Plan (2011-2015) period, China has officially launched the research and development of a new generation of marine propulsion systems. By the end of the 14th Five-Year Plan (2021-2025) period, significant progress has been made in various systems, and it is expected that the next generation of surface ships will begin to be equipped with these systems starting in the 15th Five-Year Plan (2026-2030) period at the earliest.
The characteristics of the new generation of domestically developed marine propulsion systems can be summarized in six key aspects: "Integration" (联), "Electric" (电), "Large" (大), "Quiet" (静), "Mechanical" (机), and "Compact" (小). Here’s a detailed explanation of each key aspect:
1. Integration (联):
The new generation of propulsion systems mostly feature integrated power systems. These systems not only combine multiple engines of the same type but also achieve cross-type integration—combining diesel engines, electric motors and gas turbines. This includes both "soft integration" (such as diesel-electric, gas-electric and propulsion motor combinations) and "hard integration" (such as diesel engines, electric motors, gas turbines and gearbox combinations). Representative products have already been developed, such as diesel-electric-diesel systems (used in new law-enforcement vessels) and integrated power systems (e.g., the 076 LHD).
2. Electric (电):
The new generation of propulsion systems boasts enhanced power generation capabilities, providing stronger power supply to shipboard grids. For instance, integrated power systems can deliver 20 MW or more to the warship's grid. Hybrid systems like diesel-electric-diesel and diesel-electric-gas can also supply power to the grid via shaft-driven generators. The power output of domestically produced shaft-driven generators is expected to meet the maximum electrical load of medium-sized FFGs like the Type 054/054A, and they can be integrated with the warship's independent power generation units. This will significantly support the deployment of high-energy equipment and weapons.
3. Large (大):
The new generation of propulsion systems will utilize advanced indigenous power units capable of delivering higher single-shaft output power. By the end of the 14th Five-Year Plan period, the single-shaft output power of medium-sized DDGs and FFGs was 10-25 MW, while that of large DDGs was 48-49 MW. The next generation of domestic warships will be larger in scale, requiring more powerful propulsion systems. It is expected that medium-sized DDGs and FFGs will need single-shaft power of 16-32 MW, while large warships will require single-shaft power exceeding 40 MW.
4. Quiet (静):
Due to changes in maritime defense requirements, Chinese research institutes and departments have set high standards for the noise reduction capabilities of the new generation of propulsion systems. Whether it is electric propulsion, mechanical propulsion or hybrid systems, all must have enhanced vibration damping and noise reduction capabilities. Compared to the previous generations of propulsion systems, the new propulsion systems feature meticulous design improvements in sound insulation, vibration damping and internal transmission mechanisms, which will enhance the stealth and anti-submarine capabilities of next-generation warships.
5. Mechanical (机):
The new generation of propulsion systems will continue to widely use mechanical combined-gearboxes and will incorporate advanced gearbox sets in electric propulsion systems. Since ultra-high energy weapons are not yet ready for deployment, the power demand for next-generation medium-sized DDGs and FFGs will not exceed 16 MW. Existing advanced diesel-electric units can already meet this demand. Therefore, the next generation of medium-sized DDGs and FFGs, which will be produced in large numbers, will adopt lighter mechanical transmission/hybrid systems. These systems will use shaft-driven generators and advanced diesel-electric units to provide 12-16 MW of power (equivalent to 3-4 times the power generation on the 052D DDGs). To address the large size and weight of current propulsion motors, the next generation of electric propulsion systems will introduce high-speed motors and combined gearboxes. High-speed motors are smaller and lighter, and combined gearboxes will facilitate the transmission and integration of motors and propulsion shafts, further reducing the footprint of electric propulsion systems.
6. Compact (小):
Compared to the previous generation of propulsion systems, the new generation of propulsion systems will have higher power density and a smaller footprint for the same power output, freeing up more internal space on warships. For example, the 052D DDG currently uses a combined diesel and gas (CODAG) propulsion system with four diesel-electric units (two forward and two aft), with a total power output of approximately 57 MW at maximum capacity. If upgraded to a diesel-electric-gas integrated system, the total power output could reach 72 MW, representing a 24% increase in available propulsion power and a 360% increase in power generation capacity. At the same time, the number of intake and exhaust ducts would be reduced by two, and the volume of the smokestack could be reduced by 15% or more. The transmission mechanisms of the new systems are designed with high compactness in mind, improving their adaptability and benefiting medium and light surface ships. With the introduction of high-speed motors and combined gearboxes, the overall volume of electric propulsion systems will be significantly reduced, making them suitable for small and medium-sized unmanned vessels and enhancing their overall performance.
Additionally, some specialized ships will still use cross-type alternating propulsion systems. These systems are typically custom-designed based on the ship's mission requirements and are not widely applicable, so they will not be discussed further here.
Last edited:
lcloo
Captain
From Chinese news media:-A developmental prototype of a new high-speed, high-power marine diesel (D180-20) has been fired up for the first time.
According to reports, as the first high-power high-speed diesel engine at this stage, the D180-20 diesel engine fills the gap of domestic independent high-speed diesel engine products of more than 4000kW, and CRRC Dalian Company said that the product indicators have reached the international leading level.
The official product features of the D180-20 diesel engine are as follows:
More economical: With the integrated high-pressure common rail injection system, the fuel consumption rate is significantly reduced.
More environmentally friendly: The emission level meets the EU V standard, and the pollutant emission is greatly reduced.
More efficient: The power density and reinforcement coefficient have been comprehensively improved, and the lightweight design is in line with the development trend of locomotives and EMUs.
Safer: The intrinsic safety concept and mature universal design ensure the safety of railway transportation.
Smarter: Equipped with an intelligent control PHM system to create comprehensive value throughout the life cycle.