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TMR4225 Marine Operations, 2006.02.02. Lecture content (see Course info sheet): Examples of submarines, ROVs and AUVs Work tasks for ROV and AUV in offshore operations Submarine motion equations What are you expecting to learn from todays lecture?
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TMR4225 Marine Operations, 2006.02.02 • Lecture content (see Course info sheet): • Examples of submarines, ROVs and AUVs • Work tasks for ROV and AUV in offshore operations • Submarine motion equations • What are you expecting to learn from todays lecture? • Responses are collected in a separate word document
TMR4225 Marine Operation • My objectives for this lecture: • Establish a commen knowledge on operational parameters for different types of underwater vehicles • Obtain a commen understanding of critical phases in a mission for an underwater vehicle • Documented basic understanding of dominant flow regimes during different phases of a mission for underwater vehicles
TMR4225 Marine Operations, 2006.02.02 Examples of: Submarines AUVs ROVs Work tasks for AUVs and ROVs
Lecture notes: Submarines, AUV – UUV and ROV • Notes includes web links, some may be rotten, some may be static and a few good ones are dynamic • If you know of other web sites that have relevant content on subsea vehicles, send me an e-mail • One vehicle will be used as a reference case for AUVs (HUGIN 3000) • Reference case for ROVs will be based on MIRANDA 7500 (NTNU’s own ROV)
Underwater Drilling System Submarine Drilling Vessel Bottom Template
Submarine Drilling Vessel Submarine Support Vessel Transport Container Transport Container Triton class ROV Cargo deck Consumable Replenishment System
SHEFEX recovery mission • During a sounding rocket campaign at Andøya Rocket Range in October 2005 the 300 kg payload SHEFEX was lost • Estimated impact zone was 70,3443 North and 12,1508 East • Water depth at impact zone is approximately 2700 m • Prepare a plan for the recovery mission
Lecture form • Presentations • Buzz groups • Short questions • 2-3 minutes discussions • Oral presentation of buzz group results (keyword form)
Nomenclature • SNAME H-10 Panel • ITTC standard notation for manoeuvring • Forces and moments: X,Y,Z K, M, N • Yv force coefficient for sway speed • Yvv is sway force due to sway speed, a linear damping force due to angle of attack of the vehicle • A more compact notation can be obtained by using a vector/matrix formulation of the equations of motion
Axis systems • Earth fixed system • Vehicle fixed system • Right handed system • X-axis forward • Z-axis downwards • Positive deflection of control flaps/rudders are clockwise
Buzz groups Question 1 • Inwhat layers of the ocean space are each of the vehicle types used? • Manned submarine • AUV • ROV
Buzz groups Q1 answer: • Manned submarines: • 300 m waterdepth ( large military ones operates at larger depths) • 11000 m extreme pressure vessel design (Trieste), sea space exploration • 3000 m exploration of sea bed
Buzz groups Q1 answer: • AUVs • 500 meters • Military use, mine search 150-200 m • Offshore, mapping 3000 – 4000 m
Buzz groups Q1 answer: • ROVs • Use close to structures • Not used in the wave zone • Depth limited by umbilical, down to 1000m? • Near the bottom, 1000 – 5000m
Flow characteristics for standard operations • Submarine in transit • Streamlined body • Mostly turbulent flow • Constant transit speed • Small perturbations, i.e. Sway/yaw/heave/pitch/roll speeds and angles of control planes • Close to surface (periscope depth), in the wave zone • Close to the seabed (interaction effect?)b
Flow characteristics for standard operations • AUV • Streamlined body • Constant transit speed • Small perturbations, i.e. Sway/yaw/heave/pitch/roll speeds and small angles of control planes Or: • Zero/very low speed • Large angles of attack from current • Thrusters for hovering/position keeping
Flow characteristics for standard operations • ROV • Non-streamlined body • Mostly turbulent flow due to separation on edges • Low speed • Large angles of attack; have to be able to operate in cross current • Different characteristics for up and down motion • Complex flow due to interacting thrusters • Umbilical drag can be high for operations at large depths • Tether management system can be used to remove umbilical induced motion of ROV
Types of submarines • Military submarines • Norway Ula class (dimensions?) • Typhoon type • Viking project – Nordic submarine • Cargo carrying submarines • Bulk carriers (coal, LNG, oil) • Intervention vehicles for subsea oil and gas production • Russian Lazurit project • Tourist submarines • Tropical waters • Amusement parks
Buzz groups Question 2 • Discuss why no submarine bulk carriers have been realized? • Groups 1, 3, 5, … • Discuss why non of the concepts for subsea oil and gas production submarines have been realized? • Groups 2, 4, 6, ….
Buzz group Q2 answer: • Bulk carriers • Great risks, consequences if something happens (rescue) • Environmental problems, especially if nuclear powered • More power then for surface vessels due to larger wet surface (for large slow speed bulk carriers 80-90% of resistance is viscous) • Load carrying capacity restricted due to increased steel weight • Too expensive to build and operate (high quality steel, redesign of shipyards, scraping costs, ….) • Separate terminals, high investment costs • Complex loading/unloading systems • Maintenance process must be modified • No need for this solution for ice free waters
Buzz group Q2 answer: • Submarines for oil and gas subsea structure installation and maintenance • No advantages compared to ROVs • Not useful as diver platform for large depths • High costs, both for vessel design/production and initial structure design to fit capacities of submarine • No oil company is willing to be first user of a system based on submarine intervention
Submarine summary • Submarines are hydrodynamically well designed • Commercial use of submarines is at present no alternative for subsea oil and gas production • Development of military submarines will continue, but not at the same level as before • Submarines for tourism will expand • Manned vehicles will be used for exploration of the ocean space
Submarine motion equations • 6 degrees of freedom equations • Time domain formulation • Simplified sets of linear equations
EUCLID Submarine project MARINTEK takes part in a four years multinational R&D programme on testing and simulation of submarines, Euclid NATO project “Submarine Motions in Confined Waters”. Study topic: Non-linear hydrodynamic effects due to steep waves in shallow water and interaction with nearby boundaries.
TMR4225 Marine Operations, 2006.02.02 • Sum up the 3 most important learning outcomes of todays lecture • Have your expectations been fulfilled? • If not, why not? • Feedback is written up in a separate Word document