CUVX Design Report - the AOE home page - Virginia Tech

CUVX Design – VT Team 2 Page 15power greater than 8000 kW MFLM. The IPS options must provide 30000-60000 kW pulse power for aircraftlaunch. The propulsion engines should have a low IR signature, and cruise/boost options should be considered forhigh endurance.LPD-17 Machinery Plant – Based on the ADM requirement to consider an LPD-17 modified-repeat as one of thedesign options, the LPD-17 machinery plant shall be one of the CUVX machinery plant alternatives.Sustained Speed and Propulsion Power - The ship shall be capable of a minimum sustained speed of 20 knots inthe full load condition, calm water, and clean hull using no more than 80% of the installed engine rating (maximumcontinuous rating, MCR) of the main propulsion engine(s) or motor(s), as applicable for mechanical drive plants orelectric propulsion plants. For integrated electric propulsion plants, the power required to achieve this speed mustnot be greater than 80% of the installed generator set rating following deductions for at-sea ship service powerrequirements and electric plant growth margins. To satisfy this requirement, and assuming a full load displacementof 20000 to 30000 MT, machinery plant options with total propulsion brake horsepower in the range of40000 to 80000 SHP shall be considered.Range and Endurance- The ship shall have sufficient burnable fuel in the full load condition for a minimum rangeof 4000 nautical miles at 20 knots. Endurance options up to 12000 nautical miles shall be considered. The totalfuel rate for the propulsion engines, generator sets, and auxiliary boilers to be used in determining the endurancefuel requirements shall be calculated using methods described in DDS 200-1. Fuel efficient propulsion optionssuch as diesel engines and ICR gas turbines shall be considered.Ship Control and Machinery Plant Automation – In order to reduce manning from prohibitive CVN levels, anintegrated bridge system shall be provided in the Navigating Bridge to incorporate integrated navigation, radiocommunications, interior communications, and ship maneuvering equipment and systems and shall comply withABS Guide for One Man Bridge Operated (OMBO) Ships. Propulsion control shall be possible from the shipcontrol console (SCC) on the Navigating Bridge and the main control console (MCC) at the Enclosed OperatingStation (EOS). In addition to compliance with ABS ACCU requirements for periodically unattended machineryspaces, the machinery centralized control system shall be designed to continuously monitor auxiliary systems,electric plant and damage control systems from the SCC, MCC and Chief Engineer’s office, and control thesystems from the MCC and local controllers.Propulsion Engine and Ship Service Generator Certification – Because of the criticality of propulsion and shipservice power to many aspects of the ship’s mission and survivability, this equipment shall be Navy-qualifiedand Grade-A shock certified.Temperature and Humidity – Design environmental conditions shall be based on the requirement for extendedvessel operations in the Persian Gulf. For internal combustion engines which draw combustion air from theweather, the propulsion engine ratings shall be based on the ship operating temperatures listed in Table 8.Table 8. Ship Operating TemperaturesCondition Summer WinterOutside Dry Bulb 40 degrees C -18 degrees COutside Wet Bulb30 degrees CSeawater 35 degrees C -2 degrees CFor IC engines that draw combustion air from the surrounding machinery space, engines shall be rated at the airtemperature of the machinery space and sea water temperature based on the summer conditions in Table 8.Fuel - The machinery plant shall be designed for continuous operation using distillate fuel in accordance withASTM D975, Grade 2-D; ISO 8217, F-DMA, DFM (NATO Code F-76 and JP-5 (NATO Code F-44).Steam - Steam shall not be used as a means of providing power for main propulsion. Auxiliary steam may beconsidered for catapult launch in mechanical drive alternatives.3.2.3.2 Machinery Plant AlternativesFourteen machinery plant alternatives are considered in the CUVX trade-off study. These alternatives areshown in Figure 4. Alternatives 1-5 are mechanical drive systems and Alternatives 6-14 are electric drive systems(IPS). Alternatives 1-3 are single shaft configurations that require two gas turbine engines with greater than 20000BHP each with single reduction gears. The fourth alternative is the same as the configuration used in the LPD-17,and the fifth alternative is a two shaft CODAG configuration, combining the efficiency of a diesel and the power ofa gas turbine. Alternatives 6-9 are single shaft IPS configurations that have the same propulsion engines asAlternatives 1-3, but Alternatives 6, 7 and 9 only require two generators instead of three because they use the