Spherical particles velocity in a supersonic jet flowing out from an ejector nozzle used in cold spray

摘要

The paper proposes a simplified method for calculating the velocity of spherical particles, based on a quasi-one-dimensional model, in jets flowing out from an ejector nozzles used in cold spray. The essence of the technique consists in replacing the real ejector nozzle with some imaginary Laval nozzle, in which the integral flow characteristics corresponding to the real ejector nozzle are simulated. Comparison of the velocity dependences of aluminum and bronze particles on the air pressure in the prechamber showed that they are close enough to the experimental ones (the difference is 10 - 15%). Thus, the values of the particles velocity in a jet flowing from the ejector nozzle can be calculated with good accuracy using a simplified model of their acceleration in the imaginary Laval nozzle.