Examius

🇮🇳 GATE Marine Engineering · subject

GATE Marine Engineering Naval Architecture and Ocean Engineering Syllabus

The Naval Architecture and Ocean Engineering syllabus for GATE Marine Engineering in full: 9 chapters and 71 topics, every one listed below, plus 50 Naval Architecture and Ocean Engineering flashcards with answers.

9Chapters
71Topics
50Flashcards

Naval Architecture and Ocean Engineering syllabus: all 9 chapters

Expand any chapter to see its topics and sub-topics.

  1. Ship geometry and physical fundamentals

     8 topics
    • Archimedes’ principle
    • Buoyancy and weight of ship
    • Laws of flotation
    • Heel and trim
    • Stable and unstable equilibrium of ships
    • Importance of streamlined hull shape
    • Ship main particulars
    • Hydrostatic calculations

  2. Stability and trim of Ships

     14 topics
    • Statical stability at small angles of heel
    • Inclining experiment
    • Shift of centre of gravity due to addition or removal of mass
    • Transverse movement of mass and effect
    • Free surface effect
    • Effect of suspended mass
    • Stability at large angles of heel
    • Angle of loll
    • Curves of statical stability
    • Dynamical stability
    • Probabilistic and deterministic Damage Stability
    • Different Characteristic curves of dynamic stability
    • Floodable length calculations and curves
    • Loss of stability due to grounding, docking stability

  3. Resistance and Propulsion

     19 topics
    • Components of ship resistance
    • Form factor
    • Hull roughness
    • Model testing and ship resistance prediction methods
    • Tank wall effects
    • Determination of ship resistance
    • Different series test results
    • Resistance of advanced vehicles
    • Appendage and added resistance
    • Geometry of screw propeller
    • Propeller theories
    • Hull-propeller interactions
    • Different propulsive efficiency definitions
    • Propeller cavitation and effects
    • Propeller design and series
    • Open water and self-propulsion model tests
    • Different types of propellers and their working principles
    • Propeller material, strength and manufacturing
    • Unconventional propellers

  4. Ship Manoeuvring and Motions

     9 topics
    • Ship path keeping and changing
    • Equations of motion
    • Linearised equations and control fixed stability indexes
    • Model tests
    • Stability and control in the horizontal and vertical planes
    • Definitive manoeuvres and sea trials
    • Rudder hydrodynamics, design and operation
    • Influence of propeller, hull, appendages etc. on rudder performance
    • Experimental methods for the determination of hydrodynamic derivatives

  5. Ocean waves

     2 topics
    • Regular, irregular, trochoidal
    • Wave spectrum, encounter frequency

  6. Ship Structures and Strength

     12 topics
    • Shipbuilding materials, joining techniques
    • Ship structural and framing systems
    • Bottom, side, deck, bulkhead, end structures, and structural connections
    • Primary and secondary structural members
    • Superstructure, hatch covers, machinery foundations, cargo handling systems and support structures
    • Loads acting on ships in seaway
    • Longitudinal and transverse strength considerations and estimation methods
    • Strength of hull girder, stiffened plate analysis
    • Torsion of hull girder, deformation and stresses
    • Local strength analysis
    • Reliability analysis and ultimate strength of hull girder
    • Structural vibrations, fatigue and fracture

  7. Physical Oceanography

     2 topics
    • Physical properties of seawater
    • Different types of ocean waves - tides and wind waves, and their importance

  8. Offshore Structures

     3 topics
    • Fixed offshore platforms - Jackets, Gravity platforms
    • Floating platforms - semi-submersibles, jack-ups, TLPs, FPSOs
    • Mooring, station keeping

  9. Port and Harbour Engineering

     2 topics
    • Ports and Harbours
    • Port structures - Jetties, Dolphins, Liquid berths, Dredging, Navigation

GATE Marine Engineering Naval Architecture and Ocean Engineering flashcards — 50 questions with answers

  1. State Archimedes' principle as applied to a floating or submerged body.

    A body wholly or partially immersed in a fluid experiences an upward buoyant force equal to the weight of the fluid it displaces. In symbols, $F_b = \rho g V$, where $\rho$ is the fluid density, $g$ is gravitational acceleration, and $V$ is the displaced (immersed) volume.

  2. For a freely floating ship in equilibrium, what is the relationship between buoyancy and weight, and where do their forces act?

    Buoyancy equals weight: $F_b = W$. The weight $W$ acts vertically downward through the centre of gravity $G$; the buoyancy acts vertically upward through the centre of buoyancy $B$ (the centroid of the immersed volume). In equilibrium $B$ and $G$ lie on the same vertical line.

  3. State the law of flotation.

    A floating body displaces its own weight of fluid. Thus the weight of the body equals the weight of fluid displaced: $W = \rho g V_{disp}$, where $V_{disp}$ is the immersed volume.

  4. Define the centre of buoyancy ($B$) and explain how it moves when a ship heels.

    The centre of buoyancy is the centroid (geometric centre) of the underwater volume of the hull, the point through which the total buoyant force acts. When the ship heels, the shape of the immersed volume changes, so $B$ shifts toward the lower (immersed) side.

  5. Distinguish between heel and trim of a ship.

    Heel is the transverse (athwartships) inclination of a ship about its longitudinal axis (port/starboard list). Trim is the longitudinal inclination about the transverse axis, i.e. the difference between forward and aft drafts: $\text{Trim} = d_{F} - d_{A}$.

  6. Define metacentre ($M$) and metacentric height ($GM$).

    For small angles of heel, the metacentre $M$ is the point where the line of action of buoyancy intersects the ship's centreline. The metacentric height is the vertical distance from the centre of gravity to the metacentre: $GM = KM - KG$, where $K$ is the keel.

  7. State the condition for stable, unstable, and neutral equilibrium of a ship in terms of $GM$.

    Stable: $GM > 0$ (M above G), the ship returns upright. Unstable: $GM < 0$ (M below G), the ship continues to heel/capsizes. Neutral: $GM = 0$ (M coincides with G), the ship stays at the heeled position.

  8. Describe the location of $M$ relative to $G$ for stable versus unstable equilibrium and the resulting moment.

    Stable equilibrium: $M$ is above $G$, producing a righting moment that restores the ship. Unstable equilibrium: $M$ is below $G$, producing an upsetting (capsizing) moment that increases the heel.

  9. Why is a streamlined hull shape important for a ship?

    A streamlined hull minimizes resistance by reducing form (pressure) drag and wave-making resistance, allowing smoother water flow around the hull. This lowers the required propulsive power and fuel consumption, increases attainable speed, and reduces turbulence and flow separation.

  10. Name the principal types of ship resistance that hull form affects.

    Frictional (viscous skin) resistance, wave-making resistance, eddy/form (viscous pressure) resistance, and air resistance. Total resistance $R_T = R_F + R_W + R_E + R_{AA}$; a streamlined hull chiefly reduces wave-making and form resistance.

  11. Define the ship main particulars: LOA, LBP, beam, and draft.

    LOA (Length Overall): extreme length end to end. LBP (Length Between Perpendiculars): distance between fore and aft perpendiculars. Beam (B): maximum breadth. Draft (T or d): vertical distance from waterline to the lowest point of the keel.

  12. Define freeboard and depth of a ship.

    Depth (D) is the vertical distance from the keel (baseline) to the freeboard (uppermost continuous) deck at the side, measured amidships. Freeboard is the vertical distance from the waterline to the freeboard deck: $\text{Freeboard} = D - T$, where $T$ is the draft.

  13. Define the block coefficient $C_B$ and give its formula.

    The block coefficient is the ratio of the underwater hull volume to the volume of a circumscribing box of length $L$, beam $B$, and draft $T$: $$C_B = \frac{\nabla}{L \cdot B \cdot T}$$ where $\nabla$ is the displaced volume. It indicates hull fullness.

  14. Define the waterplane area coefficient $C_W$.

    The ratio of the actual waterplane area to the area of its circumscribing rectangle: $$C_W = \frac{A_W}{L \cdot B}$$ where $A_W$ is the waterplane area, $L$ the waterline length, and $B$ the beam.

  15. Define the midship section coefficient $C_M$ and prismatic coefficient $C_P$.

    Midship coefficient: $C_M = \dfrac{A_M}{B \cdot T}$, the immersed midship area over its circumscribing rectangle. Prismatic coefficient: $C_P = \dfrac{\nabla}{A_M \cdot L} = \dfrac{C_B}{C_M}$, relating displaced volume to midship area times length.

  16. Distinguish between displacement and deadweight tonnage.

    Displacement ($\Delta$) is the total weight of water displaced, equal to the ship's total weight: $\Delta = \rho g \nabla$. Deadweight (DWT) is the carrying capacity = loaded displacement minus lightship weight (cargo, fuel, stores, crew, water).

  17. What is TPC (Tonnes Per Centimetre immersion) and how is it calculated?

    TPC is the mass that must be loaded or discharged to change the mean draft by 1 cm. $$\text{TPC} = \frac{A_W \times \rho}{100}$$ with $A_W$ in $\text{m}^2$ and $\rho$ in $\text{t/m}^3$ (the 100 converts metres to centimetres).

  18. What information do hydrostatic curves (hydrostatic particulars) provide?

    They give hydrostatic properties as functions of draft: displacement, volume, TPC, position of $B$ (KB and LCB), KM (transverse and longitudinal), waterplane area, LCF, MCT 1 cm, and the various form coefficients.

  19. How is the transverse metacentric radius $BM$ calculated?

    $$BM = \frac{I_T}{\nabla}$$ where $I_T$ is the second moment of area (moment of inertia) of the waterplane about the longitudinal centreline axis and $\nabla$ is the displaced volume.

  20. For a box-shaped vessel, give the formula for the transverse $BM$.

    For a rectangular waterplane $L \times B$ at draft $T$, $I_T = \dfrac{L B^{3}}{12}$ and $\nabla = L B T$, so $$BM = \frac{I_T}{\nabla} = \frac{B^{2}}{12 T}.$$

Show the other 30 Naval Architecture and Ocean Engineering flashcards

  1. Give the formula relating $KM$, $KB$, and $BM$.

    $$KM = KB + BM$$ The height of the transverse metacentre above the keel equals the height of the centre of buoyancy above the keel plus the metacentric radius.

  2. Write the formula for the righting moment (moment of statical stability) at small angles of heel.

    $$\text{Righting moment} = \Delta \cdot GZ = \Delta \cdot GM \sin\theta$$ where $\Delta$ is the displacement, $GZ$ the righting arm, $GM$ the metacentric height, and $\theta$ the angle of heel.

  3. Define the righting arm (lever) $GZ$ and give its small-angle expression.

    $GZ$ is the horizontal distance between the lines of action of weight (through $G$) and buoyancy (through $B$). For small angles of heel: $$GZ = GM \sin\theta.$$

  4. What approximation defines 'small angles of heel' and what assumption underlies the $GZ = GM\sin\theta$ formula?

    Small angles are typically up to about $10^\circ$–$15^\circ$. The key assumption is that $M$ remains fixed (does not move) over this range, i.e. the metacentre stays at a constant position as the ship heels.

  5. What is the purpose of the inclining experiment?

    To determine the ship's vertical centre of gravity ($KG$) and metacentric height ($GM$) in the lightship (or known) condition, by measuring the angle of heel produced by moving a known mass a known transverse distance.

  6. Give the formula used in the inclining experiment to find $GM$.

    $$GM = \frac{w \cdot d}{\Delta \cdot \tan\theta}$$ where $w$ is the shifted mass, $d$ the transverse distance moved, $\Delta$ the displacement, and $\theta$ the resulting angle of heel.

  7. In the inclining experiment, how is the angle of heel $\theta$ measured using a pendulum (plumb line)?

    A pendulum of length $\ell$ is suspended; the horizontal deflection $a$ of its bob is measured. The heel angle is given by $$\tan\theta = \frac{a}{\ell}.$$

  8. List key precautions for a valid inclining experiment.

    Calm water and weather, ship freely floating (moorings slack), minimal free surfaces (tanks empty or pressed full), no loose weights, all known weights accounted for, only essential personnel aboard at fixed positions, and accurate draft/density readings.

  9. State the formula for the vertical shift of the centre of gravity when a mass $w$ is added on board.

    $$GG' = \frac{w \cdot d}{\Delta + w}$$ where $d$ is the vertical distance between the centre of the added mass and the original $G$, and $\Delta$ is the original displacement. $G$ moves toward the added mass.

  10. State the formula for the shift of the centre of gravity when a mass $w$ is removed from a ship.

    $$GG' = \frac{w \cdot d}{\Delta - w}$$ where $d$ is the distance from the removed mass to the original $G$. The centre of gravity moves directly away from the position of the removed weight.

  11. In which direction does the ship's centre of gravity move when a mass is added, removed, or shifted?

    Added mass: $G$ moves toward the added weight. Removed mass: $G$ moves away from the removed weight. Shifted mass: $G$ moves in the same direction as, and parallel to, the shift of the mass.

  12. Give the formula for the transverse (horizontal) shift of $G$ due to moving a mass $w$ a distance $d$ across the ship.

    $$GG_H = \frac{w \cdot d}{\Delta}$$ where $d$ is the transverse distance the mass is moved and $\Delta$ is the displacement. $G$ moves parallel to the shift, causing the ship to heel.

  13. What heel angle results from a transverse shift of mass, expressed via $GM$?

    The ship heels until $G$ is again vertically below $M$. The angle satisfies $$\tan\theta = \frac{GG_H}{GM} = \frac{w \cdot d}{\Delta \cdot GM}.$$

  14. What is the free surface effect (FSE) and how does it affect stability?

    A free surface of liquid in a partly filled tank shifts toward the low side as the ship heels, moving the liquid's centre of gravity and causing a virtual rise of the ship's $G$. This reduces $GM$ and the righting arm, decreasing stability.

  15. Give the formula for the virtual rise in $G$ (loss of $GM$) due to free surface effect in one tank.

    $$GG_v = \frac{i \cdot \rho_t}{\Delta} = \frac{i \cdot \rho_t}{\rho_s \nabla}$$ where $i$ is the second moment of the free surface area about its own centreline, $\rho_t$ the density of the tank liquid, $\rho_s$ the sea-water density, and $\nabla$ the displaced volume. This $GG_v$ is the free surface correction subtracted from $GM$.

  16. For a rectangular tank of length $l$ and breadth $b$, what is the free surface moment of inertia, and how does subdividing the tank help?

    $i = \dfrac{l b^{3}}{12}$. Since FSE depends on $b^{3}$, fitting one or two longitudinal divisions (subdivisions) drastically reduces it: with $n$ equal divisions the effect falls to $1/n^{2}$ of the undivided value.

  17. What is the effect of a suspended mass on a ship's stability?

    A suspended mass (e.g. a load on a crane hook) acts as though its weight is located at the point of suspension, not at its actual position. This raises the effective centre of gravity, causing a virtual rise of $G$ and a reduction in $GM$.

  18. Give the expression for the virtual rise of $G$ when a mass $w$ is suspended a distance $h$ above its stowed position.

    $$GG_v = \frac{w \cdot h}{\Delta}$$ where $h$ is the height of the point of suspension above the original position of the mass and $\Delta$ the displacement. $G$ effectively rises to the suspension point the instant the load is lifted.

  19. Why does the small-angle stability formula $GZ = GM\sin\theta$ fail at large angles of heel?

    At large angles the metacentre $M$ no longer stays fixed because the waterplane shape changes significantly, deck edge immersion and bilge emergence alter the buoyancy distribution. $GZ$ must instead be obtained from cross curves of stability or wall-sided/Atwood's formula.

  20. State the wall-sided formula for the righting arm $GZ$ at moderately large angles.

    For a wall-sided ship: $$GZ = \left(GM + \tfrac{1}{2} BM \tan^{2}\theta\right)\sin\theta.$$ The $\tfrac{1}{2}BM\tan^{2}\theta$ term accounts for the rise of the metacentre and is valid until the deck edge immerses.

  21. What is the angle of loll and what condition causes it?

    The angle of loll is the angle at which a ship with a small initial negative $GM$ (unstable upright, $GM < 0$) comes to rest, heeled to one side but in stable equilibrium. It arises because as the ship heels, $BM$ increases until $GZ$ becomes zero with positive slope.

  22. Give the formula for the approximate angle of loll for a wall-sided vessel with negative $GM$.

    Setting $GZ = 0$ in the wall-sided formula (with $GM$ negative): $$\tan\theta_{loll} = \sqrt{\frac{-2\,GM}{BM}}.$$ The vessel lolls to this angle on either side.

  23. How does a ship at an angle of loll behave, and how should it be corrected?

    It floats heeled and can flop suddenly to the same angle on the opposite side, which is dangerous. Correction: lower the effective $G$ (restore positive $GM$) by removing free surfaces, then add low weight or ballast on the centreline / low side first, never the high side.

  24. What is a curve of statical stability ($GZ$ curve)?

    A graph of the righting arm $GZ$ (vertical axis) against the angle of heel $\theta$ (horizontal axis) for a given displacement and $KG$. It characterizes a ship's stability over the full range of heel.

  25. From a $GZ$ curve, how do you read the initial metacentric height $GM$?

    $GM$ equals the slope of the $GZ$ curve at the origin. Practically, erect a vertical at $\theta = 1$ radian ($57.3^\circ$); the height of the tangent at the origin intercepted there equals $GM$ (since $GZ \approx GM\theta$ for small $\theta$).

  26. List the key features read from a curve of statical stability.

    Initial slope (= $GM$), maximum $GZ$ and the angle at which it occurs, the range of stability (heel range where $GZ > 0$), the angle of vanishing stability (where $GZ$ returns to zero), the deck-edge immersion point of inflection, and the area under the curve (dynamical stability).

  27. Define the range of stability and the angle of vanishing stability.

    The range of stability is the span of heel angles over which $GZ$ is positive (the ship still rights itself). The angle of vanishing stability is the heel angle at which $GZ$ falls back to zero; beyond it the ship will capsize.

  28. What are cross curves of stability (KN curves) and how are they used?

    Cross curves plot the righting lever (KN or GZ assuming an assumed $KG$) against displacement for several fixed heel angles. They are used to derive the $GZ$ curve for any actual loading using $GZ = KN - KG\sin\theta$.

  29. Define dynamical stability and state how it is obtained from the $GZ$ curve.

    Dynamical stability is the work done in heeling the ship to a given angle against the righting moment, i.e. the energy needed to incline it. It equals the displacement times the area under the $GZ$ curve up to that angle: $$\text{Dynamical stability} = \Delta \int_{0}^{\theta} GZ \, d\theta.$$

  30. How is the area under the $GZ$ curve commonly computed, and what stability-criteria areas are specified by IMO?

    The area is computed numerically using Simpson's Rule. IMO intact stability criteria specify minimum areas: at least $0.055\ \text{m·rad}$ up to $30^\circ$, $0.090\ \text{m·rad}$ up to $40^\circ$ (or downflooding), and $0.030\ \text{m·rad}$ between $30^\circ$ and $40^\circ$, with $GZ \geq 0.20\ \text{m}$ at $30^\circ$ and minimum $GM \geq 0.15\ \text{m}$.

GATE Marine Engineering Naval Architecture and Ocean Engineering FAQ

What is in the GATE Marine Engineering Naval Architecture and Ocean Engineering syllabus?

GATE Marine Engineering Naval Architecture and Ocean Engineering is split into 9 chapters: Ship geometry and physical fundamentals, Stability and trim of Ships, Resistance and Propulsion, Ship Manoeuvring and Motions, Ocean waves, Ship Structures and Strength, Physical Oceanography, Offshore Structures and Port and Harbour Engineering. Together they contain 71 topics.

How many chapters are in GATE Marine Engineering Naval Architecture and Ocean Engineering?

9 chapters, containing 71 topics. The largest chapter is Resistance and Propulsion, with 19 topics.

Are there flashcards for GATE Marine Engineering Naval Architecture and Ocean Engineering?

Yes — a 50-card Naval Architecture and Ocean Engineering deck, printed in full in the flashcards section of this page and available in the Examius app with spaced repetition. The free plan covers one exam of your choice, including its flashcards; Examius Pro, a one-time purchase, unlocks every other exam and deck.