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Using modern panoramic optical measurement methods, a comprehensive experimental study of the flow structure and heat transfer in a submerged impact jet with and without chevrons was carried out. A detailed study of the influence of the presence of a flat athwart-oriented surface on the structure of the chevron jet flow on convective heat transfer was carried out. In the case of a jet with chevrons, the velocity values at the surface are shown to exceed the values of the standard round jet, and the pulsations are more intense and more uniform near the impact surface, which, accordingly, affects the heat transfer on the target. The increment in the average intensity of heat transfer of the chevron jet reaches 24%, compared with the round jet. The reason for the increment in the heat transfer coefficient is due to an increase in the number of chevrons.

The aim of this work is to study the effect of different forms of passive change in the shape of the flow on the intensity of heat transfer in the impact jet. In this work, a cycle of experiments was performed to investigate an axisymmetric jet flowing normally onto a heated surface. The jet was located both in natural conditions and during swirling of the flow (S = 0.4; 0.7; 1.0). It is shown that the intensity of heat transfer on a heated target in the case of a chevrons jet has little effect on the character, but significantly intensifies heat transfer. In the case of a swirling jet, the intensity distribution on the wall changes its character and locally increases at small distances between the nozzle and the heater.

This study investigates the development of flow and mixing processes in the stationary and impulsive transverse jets with a small degree and frequency of blowing pulsation. Velocity field measurements were carried out using the TR PIV technique. The fields of statistical moments are obtained. It is shown that when a cross flow is injected, the main flow is turbulized, while the rise of the pulsating jet depends on the outflow mode. It is shown that with an increase in the frequency of pulsations of the transverse jet, it is more strongly “pressed” against the lower wall, maximum values of the intensity of pulsations of the transverse velocity component exceed by more than 1.5 times the values of pulsations of the transverse component.