The analytical and experimental studies of the aircraft’s supersonic air intakes have been carried out. An integrated approach to the gas-dynamic designing of aircraft’s supersonic air intakes that eliminates the scale effect problem of a wind tunnel with a small-sized testing area is proposed. The designing approach accelerates the development process and reduces the resource intensity due to the rational distribution of tasks between numerical and physical experiments. The results of the unique tests of the scaled ramjet’s air intake physical model in the supersonic wind tunnel are presented.

The paper investigates the process of force interaction of a vibrating roller with a layer of asphalt concrete mixture. To describe the stress-strain state of the compacted layer during the interaction of the latter with a vibration roller, the Kelvin body was used. On the basis of the law of behavior of the Kelvin body, a simulation model has been developed, the result of which is a phase trajectory in the coordinates “force–displacement” for the system “drum–asphalt concrete mixture”. An analytical study of the characteristic points of the phase trajectory was carried out, as a result of which the relationship between the properties of the asphalt concrete mixture and the force effect in the area of contact of the roller with the compacted layer was established. In addition, a condition was obtained for continuous rolling of the asphalt-concrete layer with a vibrating roller, the observance of which makes it possible to increase the resource of the roller by reducing the wear of the latter. The results obtined can be used to establish the relationship between the operating modes of the vibratory roller and the properties of the compacted layer of the asphalt concrete mixture.

An important parameter of the compaction process of asphalt concrete mix by a vibrating roller is the resulting force exerted by the shaft on the compacted material. The magnitude and direction of this force determine the rolling efficiency and depend on the design parameters of the roller and the physical and mechanical characteristics of the compacted material. To establish these dependencies, a theoretical study of the stress-strain state of the asphalt concrete mixture in the contact zone with the vibrating roller was carried out using rheological modeling tools. Based on the obtained analytical dependences of the resulting force and the angle of deviation of the vector of the resulting force, a simulation model of the oscillatory system “roller – asphalt concrete mixture” was developed. Based on the simulation results, recommendations are given for adjusting the angle of deviation of the vector of the resultant force from the vertical. The use of these recommendations will increase the efficiency of compaction of asphalt concrete mix by reducing the number of passes of the roller, and, as a result, reducing the operating time.

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