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<div><p>The axial misalignment and tip clearance of the double spiral seals are important indexes affecting the sealing performance of the double spiral seals. In practical engineering applications, the sealing ability of double spiral seals is greatly affected by axial misalignment and tip clearance, and the coupling of assembly parameters and structural parameters of double spiral seals leads to the difficulty of seal design and use. A numerical model of spiral seals was established, and the velocity field, pressure field and critical sealing ability of double spiral seals were simulated and calculated. The influence of different axial misalignment displacements and different tip clearances on the sealing ability of double spiral seals was analyzed. The influence of axial misalignment displacement, tip clearance and rotor speed on the sealing performance of double spiral seals is obtained. The above research results provide a design basis for the engineering application of double spiral seals.</p></div>