List of top Naval Architecture and Ocean Engineering Questions on Naval Engineering

A steel deck plate of a tanker is supported by two longitudinal stiffeners as shown in the figure. The width of the plate is \( a \) and its length is 5 times the width. Assume that the long edge is simply supported, and the short edge is free. The plate is loaded by a distributed pressure, \( p = p_0 \sin\left(\frac{\pi y}{a}\right) \), where \( p_0 \) is the pressure at \( y = a/2 \). The flexural rigidity of the plate is \( D \). The plate equation is given by 

Consider the matrices 
\( M = \begin{pmatrix} 2 & 1 \\ 0 & 2 \end{pmatrix} \)

\( N = \begin{pmatrix} 1 & 0 & 0 \\ 1 & 2 & 0 \\ 1 & 1 & 0 \end{pmatrix} \)

Which one of the following is true?

A ship with a standard right-handed coordinate system has positive \(x\), \(y\), and \(z\) axes respectively pointing towards bow, starboard, and down as shown in the figure. If the ship takes a starboard turn, then the drift angle, sway velocity, and the heel angle of the ship for a steady yaw rate respectively are: 

The GZ curve for a stable ship is shown in the figure, where \( P \) is a point of inflection on the curve. Match the labels in Column 1 with the corresponding descriptions in Column 2. 

Consider an ideal Rankine cycle as shown in the figure, where \( T \) and \( S \) represent the temperature and entropy respectively. The overall efficiency of the cycle can be improved by: 

 

The arc length of the one arch of the cycloid given by \( x = t - \sin t \) and \( y = 1 - \cos t \) is ………..

Identify the type of flow from the time series plots of instantaneous fluid velocity (\( u \)) at a point.

A. \[ \begin{array}{l} I - \text{unsteady turbulent flow}; \\ II - \text{steady turbulent flow}; \\ III - \text{steady laminar flow}; \\ IV - \text{unsteady laminar flow}. \end{array} \]
B. \[ \begin{array}{l} I - \text{steady turbulent flow}; \\ II - \text{unsteady turbulent flow}; \\ III - \text{unsteady laminar flow}; \\ IV - \text{steady laminar flow}. \end{array} \]
C. \[ \begin{array}{l} I - \text{steady turbulent flow}; \\ II - \text{unsteady turbulent flow}; \\ III - \text{steady laminar flow}; \\ IV - \text{unsteady laminar flow}. \end{array} \]
D. \[ \begin{array}{l} I - \text{steady turbulent flow}; \\ II - \text{unsteady laminar flow}; \\ III - \text{unsteady turbulent flow}; \\ IV - \text{steady laminar flow}. \end{array} \]
 

A 10 m long pipe with inlet and outlet diameters of 40 cm and 20 cm respectively, is carrying an incompressible fluid with a flow rate of \( 0.04 \, \text{m}^3/\text{s} \). The ratio of the velocity at the outlet to that at the inlet is ………….. (rounded off to one decimal place).

An 80 m long barge with a rectangular cross-section of 12 m beam and 4 m draft floats at even keel. The transverse metacenter (KM) above the keel is ………. m.
 

A 100 m long ship has a cruising speed of 25 knots. A geometrically similar model of 4 m length is used for resistance prediction in a towing tank. The corresponding speed of the model is ………….. knots.

A cube-shaped pontoon with 200 tonnes of mass placed on it floats with a freeboard of 1 m in fresh water. When the mass is removed, the pontoon floats with a freeboard of 3 m. The length of the pontoon is ………. m (rounded off to two decimal places).
 

A simply supported beam is subjected to a concentrated moment \( M \) at the mid-span as shown in the figure. The magnitude of the bending moment at a distance of \( L/4 \) from the left support \( A \) is equal to: 

Consider a fluid between two horizontal parallel flat plates 5 mm apart as shown in the figure. The top plate of dimensions 0.5 m \( \times \) 2 m is towed with an applied horizontal force \( F \) of \( 0.01 \, \text{N} \), while the infinitely long bottom plate is kept fixed. The horizontal velocity profile between the plates is assumed to be linear. If the dynamic viscosity (\( \mu \)) of the fluid is \( 0.89 \times 10^{-3} \, \text{N}\text{-}\text{s}/\text{m}^2 \), then the towing velocity of the top plate is ………… \( \text{m/s} \) (rounded off to three decimal places). 

Consider a two-dimensional ship section as shown in the figure. About the point \( O \), let the sway added mass components be \( a_{22} \) and \( a_{24} \) and roll added moment of inertia be \( a_{44} \). The clockwise roll angle is considered positive. The roll added mass due to roll, about \( P \), which is at a distance \( z_p \) above \( O \), is given by: 

The open water characteristics of a propeller is shown in the figure. Match the labels in Column 1 with the corresponding descriptions in Column 2.