Design Report Guided Missile Submarine SSG(X) - AOE - Virginia ...

SSG(X) Design – VT Team 3 Page 13
Sustained Speed and Propulsion Power –
The goal sprint speed for SSG(X) is 22 knots, with a threshold of 15 knots. For the propulsor to accomplish this
speed, preliminary calculations were made by varying the hull characteristics to create a best and worst case
scenario for hull resistance. The power requirement was also calculated to propel the SSG(X) at 12 knots under
snorkel. The propulsive power requirement varies from 1750 KW to 5560 KW. SSG(X) has a threshold endurance
range of 4000 miles for snorkel transit, threshold endurance duration of 20 days at 5 knots for AIP transit, and sprint
duration of 1 hour also under AIP at a velocity no less than 15 knots.
Ship Control and Machinery Plant Automation –
One of the main goals for SSG(X) is to keep manning requirements to a minimum. To achieve this goal, a high
level of automation is required. Utilizing Commercial off the Shelf (COTS) hardware will reduce cost, improve
logistics support and provide larger customer base for improvements and upgrades.
Propulsion Engine and Ship Service Generator Certification –
Because of the criticality of propulsion and ship service power to many aspects of the ship’s mission and
survivability, this equipment shall be Navy-qualified, Grade A shock certified, and non-nuclear. To reduce
signatures a shrouded prop and an Integrated Propulsion System (IPS) is proposed.
3.1.2.2 Machinery Plant Alternatives
Propulsion system trade-off alternatives are selected to be consistent with speed, endurance, payload, and
mission requirements. From this a hierarchy of machinery alternatives is created. An excel spreadsheet is created
and filled with characteristics of data on each power plant from the manufacturer and technical papers. Table 6 lists
the data collected for each propulsion configuration. Table 7 - Table 8 display this data for the SSG(X) propulsion
options. [Pearson and Walters, Warship ’99: Naval Submarines 6]
SSG(X) Concept Exploration considers fuel cells and closed cycle diesel engines for AIP alternatives. The
propulsion system will either be an open cycle diesel or a closed cycle diesel that can run open cycle while
snorkeling. The battery options are limited to low to moderate risk Lead Acid, Ni-Cd, and Zebra batteries.
Depending on the pressure hull design, hydrocarbon fuels, oxygen, and argon will be stored inboard or outboard of
the pressure hull. Hydrogen will be stored outboard.
Table 6 – Propulsion System Data [AIP Selection]
Acronym Description
Kwsnork Kilo-watt power snorkel (kw)
Kwaip Kilo-watt power AIP (kw)
VH2C Volume Hydrogen Consumption (l/kw*hr)
VH2S Volume Hydrogen Stowage (l/kw*hr)
VO2C Volume Oxygen Consumption (l/kw*hr)
VO2S Volume Oxygen Stowage (l/kw*hr)
VArC Volume Argon Consumption (l/kw*hr)
VArS Volume Argon Stowage (l/kw*hr)
VBMaip Volume Machinery Box AIP (l/kw)
VBMdg Volume Machinery Box Diesel (l/kw*hr)
MH2C Mass Hydrogen Consumption (kg/kw*hr)
MH2S Mass Hydrogen Stowage (kg/kw*hr)
MO2C Mass Oxygen Consumption (kg/kw*hr)
MO2S Mass Oxygen Stowage (kg/kw*hr)
MArC Mass Argon Consumption (kg/kw*hr)
MArS Mass Argon Stowage (kg/kw*hr)
MBMaip Machinery Box Mass AIP (kg/kw)
MBMdg Machinery Box Mass Diesel (kg/kw)
SFC Specific Fuel Consumption (kg/kw*hr)