Progress in research
Flow Engineering engineers have developed a technological approach for the physical modeling of the company's products in the laboratory of Bauman Moscow State Technical University
Fig. 1 Original complete model of the air distribution unit
Our research objects are a series of ventilation air distribution units of the diffuser type. The main elements of this unit are, as a rule, an inlet pipe – a diffuser type connected to an air chamber of static pressure, inside the flow part of which there is a transverse plate and an outlet nozzle part, in the form of a narrowing linear channel.
The physical model of the air distribution unit is connected to the supply air source, as a rule, a channel centrifugal fan with a wide flow range and a minimum supply of 50 m3/h is used.
Two typical scenarios are possible for conducting a series of physical experiments to simulate the gas-dynamic properties of a product. In the first case, it is possible to use the original sample of the ventilation unit manufactured in the factory. In this example, the subject of diagnostics and measurements can be the parameters of full and static pressure in the flow part of the product, in those places where it is possible to install pressure selectors, and also, it is possible to use a thermoanemometer to find the parameters of an air flooded jet behind a section of a linear nozzle section. In the second case, a special transparent polymer model with a similar geometry is being prepared for the use of a modern world-class diagnostic complex widely known as PIV (Particle Image Velocimetry).
In this example, a complex of optical equipment is involved, consisting of a dual pulsed laser and a cross-correlation camera.
Fig. 2 Example of a model of similar geometry for optical diagnostics
In Figure 2, the numbers indicate: 1 – the inlet pipe of the diffuser type (manufactured using FDM 3D printing), 2 – the static pressure air chamber (SPAC), 3 – a transverse distribution plate, 4 – a narrowing linear outlet section. Positions 2,3,4 in Figure 2 are made using a CNC CO2 laser from plexiglass or plexiglass sheets. The fastening of all elements together is often carried out by means of an adhesive joint.
Fig. 3 Examples of real products prepared for optical diagnostics
Figure 3 shows products for optical diagnostics made with various features. Models for the experiment can be made either entirely of transparent polymers, or in combination with structural elements of the original metal product to achieve the best reliability and similarity of the data obtained.
Some results of optical diagnostics as an example.
Fig. 4 The outflow of a submerged jet from a polymer model
Fig. 5 Air flow in the flow part of the polymer model
Figures 4.5 show some results of optical diagnostics of the flow part of the polymer model of the ventilation air distribution unit.