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This study aims to investigate the effect of the simultaneous usage of active and passive methods (which in this case are rotational oscillation and attached splitter plate, respectively) on the flow and temperature fields to find an optimum situation which this combination results in heat transfer increment and drag reduction.

The method of the solution was based on finite volume discretization of Navier–Stokes equations. A dynamic grid is coupled with the solver by the arbitrary Lagrangian–Eulerian (ALE) formulation for modeling cylinder oscillation. Parametric studies were performed by altering oscillation frequency, splitter plate length and Reynolds number.

Oscillation in different frequencies was found to be complicated. Higher frequencies provide more heat transfer, but in the lock-on region, they bring remarkable increment to the drag coefficient. It was observed that simultaneous usage of oscillation and splitter plate may have both positive and negative effects on drag reduction and heat transfer increment. Finally F = 2 and L = 0.5 were chosen as an optimum combination.

In this study, the laminar incompressible flow and heat transfer from a confined rotationally oscillating circular cylinder with an attached splitter plate are investigated. Parametric studies are performed by changing oscillation frequency, splitter plate length and Reynolds number.

The purpose of this current study is to identify the optimal stable position of airship, with reference to spatial variation of atmospheric wind flow, so as to reduce the vibrations and thus aid in the development of control mechanism of airship dynamics.

Study of uniform flow under steady‐state conditions was carried out through the measurements of pressure and velocity in a wind tunnel at low Mach numbers on airship model (in order of size, 1:13) inclined to the uniform air stream at various angles. The measurements have been made for a range of angles of incidence, in both vertical and horizontal planes, with a Reynolds number, based on the free stream velocity and a body cross‐sectional dimension, of order of four and six, respectively. Steady‐state numerical simulations were performed, serving comparative investigation with experimental data for the specific case of the model inclined to the free stream, with orientation of side‐slip (yaw) angle β=0 and angle of attack (pitch) α=0.

The numerical results showed similar trend as found by experimental analysis. In this study, several factors such as the pressure (C_p), lift (C_L), drag (C_D) coefficients, pressure and air velocity were taken into account for comparative analysis. The analysis paved the way in identification of constructively stable position of airship model with orientation of β=0 and α=0, with respect to air flow direction.

The current findings aid in the development of control mechanism of airship dynamics.

The experimental analysis of the airship model is presented along with computational fluid dynamics analysis of optimised shape of airship model in different orientations with respect to direction of airflow.