UNDERWATER VEHICLE RESEARCH PROJECT

Mechanical details:

LOA 12.23 m.

Beam 2.71 m.

Height 3.82 m.

Draft 0.5 m.

Hull Thickness 15mm.

Freeboard 0.35 m.

Maximum operating depth 50 m.

Max speed 5 Knots

Dry weight 27 Tons

Hull diameter 1.8 m.

Hatch diameter 0.8 m.

Main thrusters 2x11.5 Kw

Vertical Thrusters 2x5 Kw

Lateral Thrusters 1x5 Kw

Power source

Rechargeable Lead Acid batteries

480 VDC - 300 Ah

24 VDC - 300 Ah(Main)

24 VDC - 300 Ah(Emergency)

Mission Duration 5 Hrs.

Passenger capacity 6 persons

Crew 3 persons

Classification agency ABS/LLOYDS OR AS REQUESTED

Forward viewport 1xhemispherical acrylic 900 mm DIA.

Water Ballast

Forward Trim tanks (port +stbd) 2x0.33 cu.m

Aft Trim Tanks (port+stbd) 2x0.33 cu.m

Variable Payload 1300 Kg

Air System

Main air 100 Liters @150bar

Reserve air 100 Liters@150bar

Total 300 Liters@150bar

Life Supports

Main Oxygen 100 Liters@150 bar

Reserve Oxygen 200Liters@150bar

CO2 Absorbent 0.125 cu.m

Monitors O2, CO2, Temp., Humidity, H2, Cabin Pressure

Emergency Life Support Minimum 72 Hrs./persons

Other Features

Navigation equipment 1xDepth Gauge

1xFluxgate Compass

1xTrim + Heel indicators

Internal light White, Red LED

External lights 24x250w

Emergency Drop Weight 500 Kg.

Emergency equipment Lifejackets

Bibs masks

First Aid Kit

Fire Extinguisher

Emergency Power supply 24VDC Supply

Scrubbers, Comms., Internal lights

Under Water Telephone 3km. range

VHF

Figures 1. General Arrangement

Figures 2. Exo-Structures

Pressure Hull

The pressure hull made from Lloyd’s Grade A(yield 38 kg/mm2) or equivalent and 15mm. thickness 7x1m. Stiffener ring, Viewports (600mm.) located on front side of the pressure hull

The main hull contains the primary pilot control and life supports control functions

Figures 3. Pressure Hull Construction

Hull Protection

A painting system together with sacrificial anodes are used to provide protection from seawater corrosion. The paint system for the pressure hull painted by

1xcoat Rea-Galvex

1xcoat Intergard Primer(EGA085/089) white

1xcoat intergard Primer(EGA 085/089) white

1xcoat interracing orange finish

Sacrificial aluminum anode are fitter to the main pressure hull and to the ballast tanks and air receivers

Figures 4 Pressure Hull and Exo-Structures Painting

Exo-Structure

The exo-structures of underwater vehicle consists basically of steel fairing supports frame and fairing, Skid, Drop weight, Thruster Supports

Figures 5 Exo-Structures Equipments

Drop Weight

Drop weight performs manual function. It located under the main pressure hull and nearly CG. The weight can be ejected from the crew by operating the manual hydraulic eject hand pump

Fairing

The fairing is manufactured from GRP(Glass Reinforced Plastic) and serves two primary purposed. Firstly for hydrodynamic purposed, to afford optimum performance of the vessel with respect to available thruster power. Secondly to minimize entanglement risk by enclosing the many protruding items of machinery, piping works and cabling associated with the vessel systems.

Figures 5 Fairing

Air Storage Cylinders

Four high pressure air storage cylinders are fitted to the outside of the pressure hull. Each cylinder is 50 liters capacity, and charged to 150 bar. The air storage cylinders are divided into two groups. Three normal ballast air storage, and one emergency air storage.

Oxygen Storage Cylinders

Six oxygen storage cylinders are fitted to the outside of the pressure hull. All cylinders are charged to 150 bar. The cylinders will be painted externally, to the same standard as the pressure hull, in order to prevent corrosion. The oxygen storage cylinders are divided into two groups. Two cylinders for normal operation and four cylinders for emergency

Penetrations

The pressure hull and hard ballast tanks are fitted with penetration, to provide air, oxygen, ballast water and electrical services.

A. Electrical Penetrators.

The electrical penetrators used on the underwater vehicle are either smooth shank, or shank threaded, with an O-ring sealing onto the external face . The external cable is bonded onto the external side of the hull penetrator

B. Air and Oxygen Penetrators

The hull penetrators for the air and oxygen systems, are all hull stopped by valves, immediately on entry into the main pressure hull. All pipework connected

Propulsion and Control

The underwater vehicle have 2x5Kw / 380 VAC /3PH /0-50Hz direct vertical drive, variable speed, bi-directional fixed thrusters in the vertical and one bow lateral positions. The verticals are housed in vectored tunnels within the fairing to afford maximum thrust with minimum entanglement potential. The lateral thruster is mounted transversally across the lower bump rail section of the exo-structure.

The main propulsion will be 2x11.5Kw /380VAC/3PH /0-50 Hz variable speed, bi-directional thrusters. All thrusters can be tuned ‘in situ’ for optimum performance in their respective operating positions under real load conditions.

All thrusters are driven by CT, DC/AC invertor controllers with fully programmable digital control. Thruster are controlled via a single 3-axis joystick with trim controls in each axis and a ‘friction set’ throttle control joystick. Steering also included. The pilots control feedback is via flat screen computer monitor readout of all control parameter

Figures 6 Main Thruster(left) and lateral Thruster(right)

Motor Controllers

Motor controllers have three controls in put option, 0-10vdc, +5vdc to -5vdc or 4-20 mA current loops. There are also digital and analog outputs to drive analog or digital meters / displays to relay motor and controller performance to the pilot’s console. Each controller has a remote motor enable / disable function making thruster isolation simple and effective

Steering

Steering is controlled using one of the three function incorporated in the 3-axis joystick controller. Joystick steering signals are buffered via the propulsion control computer and fed to the steering servo valve drive controller.

Steering is effected primarily by the main aft thruster training in the horizontal axis on aft mounted rudder pedestal, assisted by the laterally mounted lateral thruster rotary movement of the rudder pedestal is effected by a top mounted electronically controlled servomotor

Power

The vessel is powered via 240x2VDC Batteries. This main power is supplied to the main PDU(Power Distribution Unit) within the machinery space, where it is bussed together to provide the main 480 VDC propulsion power source.

Control and emergency 24 VDC battery banks are also located within the same battery box enclosures. Control and emergency power is supplied to the 24VDC ‘Main’ PDU within the controls sphere

Batteries used are Lead / Acid Heavy duty traction cells. All battery banks are fuse protected. Battery capacity is sufficient to enable 5 Hrs. of operation under normal operating condition

Lighting

The UWV(Underwater Vehicle) incorporates forward and side mounted, fixed Halogen or High Power (HP) 5600k LED light units for maneuvering purposes. Facilities to power four extra dedicated flood Power supplies and control for one 24 VDC electrical pan and tilt unit.

Communications

Surface communication are effected using a Marine Band VHF radio within the control sphere

Sub-surface communication are UWT(Under Water Telephone) operating at 10 kHz and 27 kHz in the control sphere

Life Support

UWV carries sufficient consumables to effect life support for a mission time of nine hours, plus emergency life support for 72 Hrs. for each passenger. Life support equipment includes; CO2 scrubbers, metered O2 CO2, Temperature, Humidity and barometric monitoring. BIBS(Built in breathing system) with full-face masks. Emergency, water, food, life jackets and standby soda lime storage for three persons.

Environmental Controls

UWV has and environmental control system that monitor and controls the internal atmosphere of the UWV. The system maintains the levels of oxygen, carbon dioxide, and humidity at normally accepted levels. Life supports system has been designed for an operational dive time of 5 hours with 9 persons. Plus 72 hours of emergency reserve

Oxygen System

The oxygen system on UWV is divided in to two separate sub-system Normal Oxygen and Emergency Oxygen. Oxygen cylinders are secured to the outside of the UWV pressure hull below the main deck. This allows the system to be re-charged and serviced while the UWV remains in the water. An oxygen monitor with an electro-chemical fuel cell sensor continuously monitors the o2 percentage inside the UWV. The monitor is connected to the 24VDC power supply. Two external gauges located in front of the pilot’s viewport display the normal and emergency oxygen supply pressure

Carbon Dioxide Removal

The removal of carbon dioxide from inside the submarine is achieved by re-circulating the air through CO2 scrubbers. These are filled with the CO2 absorbent SodaSorb or Soda Lime which is changed after every diving operation. The CO2 scrubbers have two power supplies available 24 VDC normal and 24 VDC emergency with a dedicated change over circuit breaker. The CO2 level is continuously monitored by The pilot, using a infrared(0 to 3000 ppm CO2) analyzer

Temperature Control

The UWV is effected by a single air conditioning unit.

Ballast Control

The UWV incorporates three ballast system; Fixed, Main and Variable

Fixed: The Fixed ballast system consists of lead ingots distributed within the exo-structure to effect neutral buoyancy of the submarine in accordance with certifying bodies documented requirements.

Main : The Main ballast system or (Soft) Ballast system consists of a collar of air filled ballast tanks situated within the fairing to provide clearance or freeboard when surfaced facilitating safe opening of the hatch whilst at sea The soft ballast can also be used as an emergency sufacing aid.

Variable: The Variable ballast or (Hard) Ballast system consists of a pressure resistant tank which can be emptied or filled the water to adjust the trim of the UWV which may change as a result of changes in payload from mission to mission.

Control of the Main and Variable ballast systems is affected via a pneumatic control panel situated within the control sphere. Externally stored HP and LP air storage cylinders located within the fairing, supply the air needed to effect ballast control. All used air is vented externally via an overboard dump valve, resulting in no cabin pressure charge.

Navigation

The UWV is piloted and navigated from the pilot’s compartment where all thruster controls ballast valves and navigation equipment are located. The pilot can navigate visually by using the front viewports. To Assist the pilot a number of navigation and safety aids will be fitted: Depth Gauges, Fluxgate Compass, Trim and heel indicator and External Lights

Fluxgate Compass

An electronic fluxgate compass allows the pilot to control the heading of The UWV. Power supplied from 24 VDC panel

Trim and Heel Indicator

The trim and heel indicator provide the pilot with an accurate indication of the attitude of the UWV. The trim angle gives the number of degrees nose up or nose down. The heel angle gives the number of degrees that the submarine is heeling to port or starboard

Instrumentation

The electrical instrumentation items in The UWV that are used to display information are the LED type with low power consumption. Battery voltages and thruster current are displayed on analogue instruments

Emergency Equipment

The emergency equipment on board The UWV comprised the following

Emergency Breathing System: This system described in the section describing H.P. Air

Emergency Lifting Point : The UWV has one lift points that can be used in an emergency. Located on the top of the hull beneath removable hatches in the fairing

Emergency Buoy Release : The UWV is fitted with an emergency marker buoy that can be released from inside the submarine. The buoy is released by selecting the Emergency Buoy Release valve opening the appropriated hull stop and operating the hydraulic ejection hand pump

Emergency Drop Weight : This system is described in the section describing the exo-structure

Emergency Life Support

Life support (Oxygen and CO2 absorbent) for a duration of 72 Hrs. is carried onboard The UWV at all time. See section describing the Environmental system. Emergency food and water should also be carried, to cover 72 hour period. A first aid kit is available inside The UWV

Emergency 24VDC Battery System

Emergency 24 VDC power is supplied to the following system, UWT, VHF, internal lights and Scrubbers. When the emergency 24 VDC supply is switched on a warning light and buzzer is activated on each panel.

Design, Construction and Inspection

Harbor Test(HAT)