Shadow Photography Method Research Articles

Оценка качества распыления комбинированного препарата для лечения инфекционно-воспалительных заболеваний горла методом теневой фотографии

Using the method of shadow photography, we diagnosed the atomization of aerosol-spray forms of Inhalypt preparations of different manufacturers by key indicators of atomization quality: dynamic characteristics and disperse composition. Comparative analysis of dynamic characteristics and disperse composition of atomization of preparations for topical application did not reveal a leader in terms of the totality of atomization indicators. Objective. Selection of the most effective preparation according to the parameter of drug transport to the oropharyngeal mucosa on the basis of comparative analysis of key indicators of atomization of aerosol-spray forms of Inhalypt preparations of different manufacturers. Materials and methods. Objects of the study: two Ingalypt brand preparations in the form of aerosols produced by Pharmstandard JSC, Russia (1), Altayvitaminy CJSC, Russia (2) and two preparations produced by Esko-Pharm LLC, Armenia (3) and Firma VIPSMED LLC, Russia (4) in the form of spray for topical application. The method of shadow photography with digital image processing using the POLIS system was used to evaluate the dynamic characteristics of spraying and disperse composition of the spray. Results. On the basis of experimental data on determination of dynamic characteristics and disperse composition of aerosol and spray atomization of preparations of different manufacturers, compliance of the studied atomization parameters with optimal atomization of aerosol-spray forms for topical application was evaluated. Atomization parameters of preparations Nos. 1, 2 and 3 approximately equally correspond to the optimal dynamic and dispersion characteristics, but preparations No 1 and No 2 have a non-dosed aerosol form, which is less preferable in comparison with the dosed spray form, to which preparations No 3 and No 4 belong. The disadvantage of preparation No 4 can be considered to be its narrow cone of atomization. Conclusion. Comparative analysis of the dynamic characteristics and disperse composition of the spray of Inhalypt preparations obtained by the method of shadow photography did not reveal a leader among these preparations in terms of atomization parameters. Pharmstandard aerosol produces an optimal spray in terms of dynamic and dispersion characteristics, but its underdosed form is the main disadvantage of the drug. Key words: shadow photography method, Inhalypt, dynamic spray characteristics, dispersed spray composition

The Effect of the Angle of Pipe Inclination on the Average Size and Velocity of Gas Bubbles Injected from a Capillary into a Liquid

This work is devoted to an experimental study of the effect of coalescence on the average diameter and velocity of gas bubbles in an inclined pipe. The measurements were carried out for agas flow rate of 3.3 and 5 mL/min at pipe inclination angles of 30–60°. The study of gas bubble diameters was performed using a shadow photography method. The values of the average diameter and velocity of the bubbles were obtained depending on the angle of inclination of the pipe. A map of regime parameters was constructed at which gas bubbles form a stable structure—a chain of bubbles with an equal diameter.

EFFECT OF THE ANGLE OF PIPE INCLINATION ON AVERAGE SIZE AND SIZE DISTRIBUTION OF GAS BUBBLES INJECTING FROM A CAPILLARY TO LIQUID

The paper presents an experimental study of the size distribution of gas bubbles in an inclined pipe. The measurements were carried out for gas flow rate 3.3 ml/min, at pipe inclination angles of 30-60 deg. The study of the gas bubble diameters was performed using the shadow photography method. The values of the average size of bubbles and the size distribution of bubbles were obtained depending on the angle of inclination of the pipe and the distance from the location of the gas phase injection the measurement point.

Formation of the microchannel structure of a spark discharge in air in the gap spike-plane

The formation of the microchannel structure of a spark discharge in the gap spike (cathode)-plane of 1.5 mm length in the air of atmospheric pressure was studied by the method of shadow photography. The images with the concurrent descent of microchannel diameter sand the number of microchannel increase in the cathode region on the time interval of 5 ns were recorded. The obtained data are explained in the frames of the microstructure formation mechanism at the expense of the front instability of the ionization wave. The parameters characterizing the process of the microstructure formation are estimated, and they agree with the experimental data. Keywords: spark discharge, ionization wave, ionization instability, microstructure, method of shadow photography.

Формирование микроканальной структуры искрового разряда в воздухе в промежутке острие-плоскость"

The formation of the microchannel structure of a spark discharge in the gap spike (cathode)-plane of 1.5 mm length in the air of atmospheric pressure was studied by the method of shadow photography. The images with the concurrent descent of microchannel diameter sand the number of microchannel increase in the cathode region on the time interval of 5 ns were recorded. The obtained data are explained in the frames of the microstructure formation mechanism at the expense of the front instability of the ionization wave. The parameters characterizing the process of the microstructure formation are estimated, and they agree with the experimental data.

Влияние предыонизации на микроканальную структуру искрового разряда в воздухе в промежутке острие-плоскость

The initial phase of a spark discharge in the gap between the pin (cathode) and a plane 1.5 mm long in atmospheric pressure air under conditions of preliminary photoionization by an auxiliary discharge was investigated by the method of shadow photography. In the absence of preionization, the discharge from the first nanoseconds after breakdown is an aggregate of a large number of micron-diameter channels. It was found that the electron concentration resulting from preionization, estimated at 108  109 cm-3, increases the degree of uniformity of the discharge channel in the near-cathode region; however, in the near-anode region, the channel remains microstructured. Within the framework of the mechanism of microstructure formation due to the instability of the ionization wave front, a criterion for the formation of a uniform discharge is obtained and an explanation of the results obtained is presented.

Microchannel structure of a spark discharge in a pin to plane " gap at different air pressures

Using high-speed photography and shadow photography, the structure of the glow and the microstructure of the spark discharge in a 1.5 mm long "pin(cathode)-plane" gap in air in the pressure range from 300 to 760 Torr has been studied. The presence of a microchannel structure of the discharge in the indicated pressure range was established --- the discharge is a aggregation of a large number of micron-diameter channels. It is shown that with decreasing pressure, the evolution of the microstructure and glow of the discharge lags behind the onset of breakdown, however, their morphology retains similarity at different pressures Keywords: spark discharge, microstructure, method of shadow photography, high-speed shooting.

Dynamics of structure of pulsed discharge in nitrogen and argon at different pressures in a "pin to plane" gap

Using high-speed shooting and shadow photography, the spatial structure of a pulsed discharge in a 1.5 mm long "pin(cathode)-plane" gap in nitrogen and argon in the pressure range from 0.25 to 2 atm was studied. It has been found that a spark discharge is realized in nitrogen and a diffuse form of discharge is realized in argon. For both cases, the presence of a microstructure of discharges in the studied pressure range was found, when the discharge is an aggregation of a large number of micron-diameter channels. It is shown that for each gas the dynamics of the discharge glow structure remains similar at different pressures. It has been established that the glow and microstructure of the discharge in nitrogen are similar to those in air. Keywords: spark discharge, diffuse discharge, microstructure, method of shadow photography, high-speed shooting.

Influence of preionization on the microchannel structure of a spark discharge in air in a pin-plane gap

The initial phase of a spark discharge in the gap between the pin(cathode) and a plane 1.5 mm long in atmospheric pressure air underconditions of preliminary photoionization by an auxiliary discharge wasinvestigated by the method of shadow photography. In the absence ofpreionization, the discharge from the first nanoseconds after breakdown isan aggregate of a large number of micron-diameter channels. It was foundthat the electron concentration resulting from preionization, estimated at108-109cm-3, increases the degree of uniformity of the discharge channel inthe near-cathode region; however, in the near-anode region, the channelremains microstructured. Within the framework of the mechanism ofmicrostructure formation due to the instability of the ionization wavefront, a criterion for the formation of a uniform discharge is obtained andan explanation of the results obtained is presented. Keywords: spark discharge, preionization, photoionization, instability of the ionization front, microstructure, shadow photography method\

Comparative analysis of the dispersion quality of oxymetazoline nasal sprays.

Metered-dose nasal sprays (MDNS) are the most widely used for treating rhinitis. Medicinal preparations in the pharmaceutical market vary in their characteristics. To identify the most effective drug, it is necessary to compare the preparations regarding various parameters. The purpose of the research was to compare oxymetazoline MDNS of different brands regarding their dispersion qualities. To that end, nine oxymetazoline sprays available in the Russian market were chosen and analyzed considering their dynamic characteristics and the spraying dispersion composition. The research was conducted with the shadow photography method, the selection of which was justified by its simplicity, the possibilities for detecting the spray jet composition, the process of its formation in dynamics, and the possibility for measuring droplets of all forms. Momentary images of spray activation phases, as well as an averaged image of 100 shots of the spraying main phase, were obtained. According to a range of characteristics, such as spraying duration, a cone angle and cone structure, all the preparations were grouped into three categories. It was found out that the sprays from Group 2 had the best dynamic rates of dispersion, with Vicks Sinex having the best results. Regarding the distribution of particles of different size, the most optimal composition was found for the drugs from Group 2, particularly, Vicks Sinex and Afrin preparations. Hence, Vicks Sinex spraying regimen and microsprayer design were found the most effective for delivering the medicinal substance to the destination.

Coal-water slurry atomization in a new pneumatic nozzle and combustion in a low-power industrial burner

A new pneumatic nozzle for spraying coal-water fuel based on the near-wall and cumulative jets and Coanda effect has been tested. The mechanisms and characteristics of CWS spraying and combustion have been investigated. To prepare the CWS, Kuznetsk oxidized coal of grade D (long-flame) was used in proportion to water of 55/45. The disperse composition of water and CWS droplets was measured at the nozzle outlet using the shadow photography method. The characteristic size of liquid CWS droplets in the ignition region is 20 µm. At the same time, the flow contains coal particles with a size of about 100 µm. This size of particles is sufficient for efficient combustion. The principle possibility of efficient joint combustion of CWS and pulverized coal fuel with the help of the developed burner is shown at the uncooled fire setup with an uncooled 5-MW furnace. The experiments were carried out at a power of 1 MW and water content in CWS of 45%. NOx emissions meet the MPC requirements for coal-fired boilers. Emissions of other substances are close to zero even with suboptimal operating and design parameters. The results obtained can be used in numerical simulation of the processes of CWS dispersion and combustion. Further work should be aimed at optimizing operating parameters in application to industrial conditions and at developing practical recommendations for boiler design.

Investigation of characteristics of a pneumatic nozzle as applied to coal-water fuel spraying

A gas-droplet flow, formed by spraying liquid with a pneumatic nozzle was studied in a wide range of parameters. Information on the distribution of particle sizes was obtained using the method of shadow photography. High-speed visualization of the flow was performed. The nozzle operating regimes of a steady gas-droplet flow generation were identified.

Spraying Liquid Using Pneumatic Nozzle for Suspension Fuel

Characteristics of gas-droplet flow created by spraying a liquid using an advanced pneumatic nozzle for suspension fuel were studied experimentally. The measurements were made using the shadow photography method. On the example of water, the disperse composition of the gas-droplet flow, jet expansion angle, and flow structure stability were determined for different regimes. It was shown that most droplets were less than 10 $$\mu$$ m in size. The disperse composition of the flow remained unchanged for a wide range of operating parameters. The nozzle designed generates droplets of a size sufficient for efficient combustion of suspension fuel under real conditions.

Liquid fuel spraying by a high-speed steam jet

The direct shadow photography method was applied for study of the size distribution of droplets produced in liquid fuel atomization by a high-speed jet of superheated steam. This approach for fuel spraying allows eliminating the clogging of fuel lines and atomizers used for combustion of substandard liquid hydrocarbons. The setup has a long-focus microscope lens with optical magnification 7:1; this allows measuring the particles with the size starting from 1 µm. Experiments revealed that the prevailing size of droplets in the fuel spray is 1–2 µm.

Investigation of the structure of the gas flow from the nozzle of a spray-type burner

The flow structure in a high-speed gas jet released from the nozzle of a promising liquid-fuel spray-type burner is studied experimentally and theoretically. The velocity distribution in a single-phase gas flow is measured by means of particle image velocimetry (PIV) at various operating parameters. Using the one-dimensional isentropic flow approximation, the gas-dynamic parameters are estimated for the characteristic operating regimes of the burner with supply of superheated water steam, as well as with air supply. With the use of the ANSYS Fluent CFD package, two-dimensional numerical simulation of aerodynamic structure of air stream from the nozzle is carried out. The results are compared with the measured velocity field and the flow pattern, typical of a supersonic underexpanded jet, visualized by the direct shadow photography method near the nozzle orifice.

The study of disperse composition of the gas-droplet flow when spraying diesel fuel by a steam jet

The disperse composition of the gas-droplet flow was studied experimentally when spraying diesel fuel by a jet of superheated steam in a burner device with good prospects. The studies were performed using the method of shadow photography (SP). In a wide range of operating parameters (steam and fuel flow rate) corresponding to the area of stable operation of the burner, size distributions of fuel droplets were obtained. Dependencies of the droplet size in the flow on the steam and fuel flow rate were determined.

Investigation of a promising method for spraying liquid hydrocarbons using the shadow photography method

A promising method for spraying liquid hydrocarbons by a high-speed jet of superheated steam was studied experimentally. Information on the disperse composition and structure of the gas-droplet flow during the spraying of used transmission automotive oil was obtained using the method of shadow photography. Size distributions of fuel droplets were obtained in a wide range of operating parameters (flow rate and temperature of steam, fuel consumption).

Comparative analysis of Kameton spraying parameters of different manufacturers

Based on a comparative analysis of the key dispersion parametries of spray-aerosol forms of drugs Kameton from different manufacturers the most effective drug in terms of delivery to the mucous membrane of the throat was choosen. The objects of study were 5 drugs brand Kameton, produced in the form of a metered-dose spray manufacturers of 'Firm 'VIPSMED' (RF), 'Altayvitaminy' (RF), 'Samaramedprom' (RF), 'ESCO-Pharm' (Armenia) and metered-dose aerosol - of 'Pharmstandard' (RF). Measurement of the dynamic characteristics of the spray and the dispersed composition of the spray was carried out by the method of shadow photography with digital image processing using the 'POLIS' system. Diagnose spray pattern spray angle and the shape of the cone spray pattern showed that the spray pattern is in the form of a wide hollow cone is in the drugs Kameton production of 'Firm 'VIPSME' and 'ESCO-Pharm' (Armenia). The study of the parameter 'spray duration' showed that in all studied sprays the classical three-stage spray is carried out. In the aerosol production of 'Pharmstandard' no initial and final stage, spraying takes place in jet, without forming a cone. The calculation of the proportion of the duration of the main stage to the total duration of the spray showed that the maximum value of this parameter is achieved in the spray production of 'Firm 'VIPSMED'. A comparison of five drugs Kameton dispersed composition showed that the drug Kameton production of 'Pharmstandard' refers to the fine, and the others studied - to the coarse aerosols, which is more preferable. A comparative analysis of the drugs Kameton five different manufacturers showed that the most effective mode of operation of the spray packaging system, providing the most favorable conditions for the delivery of the drug to the mucous membrane of the throat, is carried out in drug production of 'Firm 'VIPSMED'.

Investigation of Spark Discharge Dynamics in an Air-Filled Point–Plane Gap by Shadow Photography

The microchannel structure of a spark discharge in a 1.5-mm-long point–plane gap has been studied by the method of shadow photography. The discharge dynamics (propagation of microchannels from the point into the discharge gap, branching and expansion of the microchannels, formation of a joint front of the spark’s shock wave and its motion) has been observed over a time from several nanoseconds to several hundred nanoseconds. Objects of a half-ring shape have been discovered. They have been identified as semispherical shock waves resulting from the formation of microcraters near sites where the microchannels touch the plane electrode.

Исследование динамики искрового разряда в воздухе в промежутке острие--плоскость методом теневого фотографирования

AbstractThe microchannel structure of a spark discharge in a 1.5-mm-long point–plane gap has been studied by the method of shadow photography. The discharge dynamics (propagation of microchannels from the point into the discharge gap, branching and expansion of the microchannels, formation of a joint front of the spark’s shock wave and its motion) has been observed over a time from several nanoseconds to several hundred nanoseconds. Objects of a half-ring shape have been discovered. They have been identified as semispherical shock waves resulting from the formation of microcraters near sites where the microchannels touch the plane electrode.