In order to overcome the disadvantages of the computational fluid dynamics(CFD)method such as high computational cost and the inability to reuse the computational results
a steady prediction model of pressure and velocity fields for NACA0018 airfoil in α=2°-8°
Re=0.1×10
6
-1.6×10
6
is established based on deep-learning method using 132 sets of two-dimensional flow data. The energy conservation equation of incompressible flow at low velocity is used as the constraint condition. Considering the correlation between lift drag and surface pressure
an activation function is proposed. The results show that for pressure field prediction the average e
rror of the traditional neural network is about 2.77%
but for velocity field prediction that of the traditional neural network is 11% and the maximum is 26.993%
while the average error of the improved neural network is only 2.77%. Compared with the traditional activation function
the improved activation function neural network is more accurate in predicting airfoil velocity field and the flow field transition is more uniform. Compared with the traditional CFD method
the neural network can obtain the flow field in a few seconds
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