International Scientific Journals
of Scientific Technical Union of Mechanical Engineering "Industry 4.0"

We present and explain the mathematical apparatus used in a numerical simulation model created with АNSYS СFX Software. The purpose of the model is to perform computations of fog parameters in different points of artificially generated fog sprays, which are then used to calibrate a novel type of fog sensors. By changing the distance between the nozzle and the measuring laser beam of the sensor, we can assess how the number flow rate and diameter distribution of fog droplets are varied within in the spray. This work is related to improving European security by introducing systems for quick counteraction to terrorist attacks, industrial accidents and natural disasters. These systems use artificial fog generation to collect and deposit on the ground harmful aerosols dispersed in air, especially CBRN agents. Our newly developed fog sensors operate on the basis of the electromagnetic echo effect to control the decontamination process. In order to optimize the work of the sensors, it is crucial to investigate fogs and their ability to absorb harmful substances from air. The most important fog parameters that influence the efficiency of the cleaning process are the number of droplets and their size.

Automated optical scanning systems for analysis of solid surfaces are presented in this work. The prototypes are capable of detecting various parameters and irregularities related to the surfaces of solid bodies by measuring the amplitude of modulated signals of the Electromagnetic Echo Effect. The systems allow various sizes of all kinds of surfaces to be scanned and the results to be visualized on a computer screen. The aim of this work is to present two prototype versions (which use analogue and digital measuring devices) and to show their capabilities. Their general purpose is to scan different areas of specimens and visualize their sensitivity to the Electromagnetic Echo
Effect onto a plot of coordinates but they are also capable of providing valuable information about structural, mechanical and electrical surface parameters.

In this work a new device for measuring the parameters of a fog is described. It is developed by our team and is called Fog Detector Indicator 1 (FDI-1). It is a part of a sensor system for control of the parameters of a fog which is used for decontamination of objects polluted by different circumstances. FDI-1 is a custom indication unit used in various systems for evaluation of fog parameters that gives the operator a visual result for the change of the input voltage. The main function of the indicator is to show the measured voltage applied on its coax input. Usually, this measurement can be done with a regular voltmeter, but the nature of the measurement of a fluid (fog) density, droplet diameter or contamination assumes very rapid changes of the measured values and also very short peaks of the maximum and the minimum of the measured variable. FDI-1 is can be used namely in such cases.

The current work is related to improving security by developing a new type of fog sensors and devices. We investigate fogs and their ability to absorb and clean various pollutants from air, including chemical, biological, radiological and nuclear (CBRN) agents. Fog can be used very effectively for counteraction to terrorist attacks and weapons of mass destruction, as well as for prevention of industrial accidents and disasters. It is crucial to study the specific sizes of fog droplets, which optimally collect dangerous substances. We present a computational fluid dynamic model for estimating droplet number flow rate through a laser beam. It shows, that we can make a quantitative assessment of both the number flow rate and the droplet diameter distribution. After we have confirmed that it is possible to monitor these parameters, we proceed and investigate how they are varied, when the laser beam’s distance from the nozzle is changed. Thus, by selecting the distance between the laser beam and the nozzle, it will be possible to measure the diameters and the number of fog droplets. Different nozzles can be simulated easily by entering their output parameters (mass flow rate, diameter distribution, orifice diameter) in the setup.

The current work is related to improving security by developing a new type of fog sensors and devices. We investigate fogs and their ability to absorb and clean various pollutants from air, including chemical, biological, radiological and nuclear (CBRN) agents. Fog can be used very effectively for counteraction to terrorist attacks and weapons of mass destruction, as well as for prevention of industrial accidents and disasters. We present a device developed by us – Fog Detector 3 (FD-3), which main purpose is to continuously monitor the atmospheric air and to produce analogue signal proportional to the density of any present aerosols, including water fog. The main components of the device, as well as their connections and way of operation are described.

А relatively inexpensive instrument (for fog density control), which works in the visible specter, is presented. Its purpose will be to alert the occurrence of fog or visible pollution in the air. It can also detect, if the cleaning fog has reached all areas. This equipment can be used to assess the density of fog. The device is designed for continuous monitoring of the atmospheric air and detection of dispersed agents in the form of aerosols. The total concentration of aerosols is measured and if it exceeds the pre-set threshold, an indication is given via a LED and the information can be exported to external systems. The principle of operation of the device is based on the spectrophotometric method. A beam of monochromatic light is passed through the investigated environment and its intensity is attenuated by the presence of pollutants. The hardware of the device is described, as well as its construction, software and the measuring procedure.

The current work is related to development of sensors for contamination detection, and systems, which use fog as a cleaning agent, in order to prevent disasters and accidents, and to help acting against terrorist attacks and weapons of mass destruction. Investigations in laboratory conditions of several types of mist generators are presented. For this purpose, various products, which create aerosols, were researched. The diameter distributions of the droplets, produced by them, were experimentally determined. For development purposes, several simple devices for easy fog generation are chosen. This study is related to the development of sensors for fog with different characteristics. The obtained results allow a proper selection of sprayers to be made, so that the necessary conditions for the development of sensors are ensured.