Re:
Pardon me, but, as an engineer with some nuclear background, these statements do not make sense. If anything the original piping designs (including pumps) selected using standard design principles of the time proved to be a major noise source, and the subsequent designs used LARGER pipes to reduce it.
That is not correct. What the intent is to achieve is to reduce friction flows to enhance natural circulation. The longer the pipes, the greater the friction. Its not a question of using larger pipes but less pipes.
There are also 3 different piping systems in the powerplant. 1st there is the reactor loop that transfers the heat from the reactor core to the (2nd) steam loop via a heat exchanger. The second loop uses the heat from the first loop to generate saturated steam which drives the turbine to propel the submarine. Waste heat from the 2nd loop is expelled to the 3rd via another heat exchanger, called the condenser (because it condensing any remaining steam into water). The 3rd loop is the cooling loop where the heat from the condenser is transferred to sea water and discharged. Each loop has its own pipes and pumps.
If I'm not wrong, a PWR has an added loop compared to a BWR. Each type of reactors works differently. There is such a thing as loop arrangement.
Thank you for this reference you provided.
https://netfiles.uiuc.edu/mragheb/w...wer Engineering/Nuclear Marine Propulsion.pdf see pages 8 and 9. The S5G prototype and S8G production design have a significantly different engineering compartment layout in order to achieve natural convention flow at reduced power levels.
That is what's written. However, the assumption is that the S9G does not actually use natural circulation technology. Actually in commercial power generation, most if not all gen III nuclear reactors all use natural circulation as a key feature of the reactor.
Lastly, we are discussing a replacement for the Ohio class SSBN, which the S8W was designed for, not the Los Angeles SSN [S6G], Sea Wolf SSN [S6W], or Virginia class SSN [S9G]. Comparison between the Los Angeles class and Virginia class noise levels at 25 knots give little indications about their comparison to the noise level of an Ohio at 12 knots.
Yup, and the argument why the S9G can't be used has not been argued. The LA class S6G uses a surface ship D2W nuclear reactor core.
The S8G suffers from a refuel requirement which increases added cost. The land based version's core got replaced with the sea wolf's S6W core. Its also a 30 year old reactor.
Reactors like engines need to fit the ship. Instead of arguing for the sake of arguing, I merely wish to address your original contention is that the S8W reactor could be used to reduce development cost. This is still not tenable in view of the refuel requirement. In fact, I have suggested that the S9G reactor would have formed a better argument on the same basis.
The argument that it is a reactor used for a SSBN or a SSN is irrelevant. Its like arguing an aircraft engine should never be put into a tank. The relevant issue is whether the S9G reactor can be used for a boomer. Still haven't read anything that says it can't.
As to the sound requirement, the minute you can highlight what is the noise level of a virginia, I'd gladly indicate whether that is sufficient for a boomer. If you can't, then the arguments about noise level of the S9G is again specious and just merely arguing for the sake of argument ie non-factual.
