In the current application of flat nosecones in the missiles
the disadvantages such as low front space use efficiency
difficulties in the manufacturing
and poor transmission performance bring about a great demand for the integration of a class function/shape function transformation technique(CST) based flat nosecone to an axis-symmetrical front-tip with a ‘front-tip-down angle’. The ‘front-tip-down angle’ was used to realize the smooth transition of the merging region. The computational fluid dynamics calculation results were obtained for the axis-symmetrical nosecone
the flat nosecone
and the integrated nosecone at ‘front-tip-down angle’ varying from 0 to 5 degree. The results showed that the maximum lift-drag ratios of the axis-symmetrical nosecones
the integrated nosecones at zero angle of front-tip-down
and the ones at non-zero angle of front-tip-down were 8158%
8616%
and 8946%
respectively
to that of the flat nosecone. An optimization was processed in order to obtain the maximum lift-drag ratio and lift coefficient in the integrated nosecones at 2 and 3 degrees of “front-tip-down angle”. In the 2 and 3 degrees of “front-tip-down angle” cases
lift-coefficient pareto-optimal fronts increased by 599% and 416%
lift-drag ratio pareto-optimal fronts decreased by 1996% and 1839%
respectively
while the terminal radius of the axis-symmetrical front-tip increased from 150 mm to 210 mm. Furthermore
when the terminal radius was less than 165 mm
the lift-drag ratio in the configuration with 2 degrees of “front-tip-down angle” was larger (peak value could reach up to 9779% to that of flat nosecone). While the terminal radius was larger than 165 mm