The process of grid generation and flow field simulation in CFD calculation can be automated to enhance the efficiency of CFD simulation, which has a great potential for applications. An Auto-CFD technology framework based on the tie-dye algorithm which can generate grids automatically and initiate inviscid supersonic flow field calculation quickly without geometry clean-up after inputting solid models. A 2D numerical example verifies that the calculation accuracy of this technology is comparable to that of the unstructured finite volume method, but with a significant improvement in calculation efficiency. An Auto-CFD software that can start the calculation in real time based on hand-drawn models was developed in theory, which can automatically simulate any two-dimensional irregular shape. The Auto-CFD technology was also extended from 2D to 3D space, and the irregular point cloud obtained by laser scanning the car was used as the solid model to demonstrate the adaptability of this technology to complex shape problems. The Auto-CFD technology framework developed based on the tie-dye algorithm is compatible with mainstream difference schemes and has good mesh adaptability, which is expected to solve the technical problems existing in existing Auto-CFD software.