DEVICE FOR FORMING A STRATIFIED LIQUID FLOW IN MICRO- AND MINI-CHANNELS Russian patent published in 2023 - IPC F28D13/00 F28F13/02 F28D1/03 H05K7/20 

FIELD: energy; heat engineering.

SUBSTANCE: invention can be used in cooling systems for equipment in solar energy and relates to the creation of a device for forming a stratified fluid flow in micro- and mini-channels in order to significantly intensify heat transfer and increase the cooling efficiency in systems with mini-channels. It is achieved by the fact that the device for forming a stratified liquid flow in micro- and mini-channels includes a flat mini- or microchannel of rectangular cross section with a two-phase flow of liquid and gas or vapour simultaneously supplied to the channel from parallel inlet nozzles, a substrate that forms the bottom channel wall, with one or more electronic fuel elements embedded in the substrate in its centre. Along the channel on the surface of both of its side walls, in their central part, there are longitudinal microgrooves forming a stratified mode of fluid flow, dividing the flow area of the channel into the gas phase region and the liquid phase region. The microgrooves have the shape of a triangle or a rectangle and are made in such a way that the angle between the plane of the side wall of the channel and the side of the microgroove is 90 ≤ α ≤ 135 degrees. On the inner surface of the side walls of the channel in the gas phase region, the upper wall of the channel and on the surface of the grooves, a continuous hydrophobic nanocoating is additionally applied, which limits the flow of liquid, while the size of the nanostructures is 1-500 nm, and the difference between the equilibrium contact angle of wetting on the hydrophobic surface and the equilibrium the contact angle of wetting on the hydrophilic surface, which is the surface of the liquid flow, is 10-175 degrees.

EFFECT: creation of a device for forming a stratified fluid flow in micro- and mini-channels in order to significantly intensify heat transfer and increase the cooling efficiency in systems with mini-channels.

2 cl, 3 dwg