PSI - Issue 54

Wojciech Skarka et al. / Procedia Structural Integrity 54 (2024) 498–505 Bartosz Rodak/ Structural Integrity Procedia 00 (2019) 000 – 000

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3. Aerodynamic optimization methods Aerodynamic optimization is the process of finding the shape of an object that provides the minimum aerodynamic drag. Aerodynamic drag is the force that opposes the movement of an object through the air. The lower the aerodynamic drag, the faster and more efficiently an object can move. In this case, the finite element method was used in the ANSYS Fluent environment in combination with the optimization module. The methods they used were design of experiments [2] and gradient method [3], [4]. The idea of optimisation of the particular fragment is to solve the partial fragment of the shape decisive in the opinion of the designer or aerodynamicist about critical aerodynamic features such as drag or lift force. Examples of such important parts of the structure are, for example, the front wheel surrounding in the car [5], the exterior mirror in the car, or the mounting of the gondola under the wing or fuselage. Such fragments can be solved with certain restrictions independently of the rest of the structure. such verified computational methodologies can be used and developed in models developed in accordance with the MBD (Model Based Design) methodology [6] or for the development of generativemodels [7]. 4. Profile optimization by Design of Experiments method Full aerodynamic simulation of the element connecting the wing to the nacelle was carried out in the ANSYS Fluent environment. The dimensions of the individual points and their allowable values in the design of experiments [2], [3] module are shown in Table 1. Instead of the first point, a rounding was used on the leading edge with a radius that was an input parameter. The height of the connecting element in this test is fixed at 50mm

Table 1. Summary of node dimensions and their limits.

Direction

Nominal dimension

Maximum dimension

Minimum dimension

Point

0 0 2

X Y X Y X Y X Y

0 0

0 0

0 0

40mm

36mm

44mm

2 3 3 4 4 Edge round

13mm 130mm 4mm 200mm 0 1mm

11,7mm 117mm 3,6mm 180mm 0 0,5mm

14,3mm 143mm 4,4mm 220mm 0 8mm

Air velocity: 30m/s After simulation, the aerodynamic drag for the input geometry was calculated to be 0.0681N Once the simulation of the connecting element with the base geometry was done, the optimization process proceeded. The first step in optimization using the design of experiments method is to create an optimization plan based on the input parameters. The experiment plan was created in the design of experiments module in ANSYS software. The maximum and minimum values of the coordinates of each spline node, i.e. the input parameters, were taken into account. The experiment plan was to obtain the maximum entropy for the input parameters. For each experiment, an identical simulation was performed as for the base geometry. Table 2 below shows which input parameters gave the best result in terms of the smallest output parameter value.

Table 2. Coordinates of spline nodes, forming the optimal geometry.

Direction

Nominal dimension

After optimization dimension

Point

0

X

0

0