Effect of Rheological Properties of Aqueous Solution of Na-CMC on Spray Angle for Conical Pressure-Swirl Atomizers

Abstract

Aerosol is a multiphase system, created as a result of the dispersion of a liquid in a gaseous medium. The atomized liquids are most often water and fuel; however, they can be any other substance. Even a small addition of a substance that changes the rheological properties (i.e., the nature of the flow) can change the properties of the resulting aerosol. The most important parameters that characterize the aerosol are the outflow rate, the droplet diameter, the spray spectrum, and the spray angle. The latter is important when selecting atomizers, especially those working in groups on the sprayer boom. The spray angle is an important parameter of the atomization process, providing a great deal of information about the quality of the spray. This study presents the results of rheological tests and the atomization of aqueous solutions with varying concentrations of sodium carboxymethylcellulose (Na-CMC). We found that the spray angle decreased with increasing Na-CMC concentration in the solution, which is attributable to an increase in shear viscosity. The design of the atomizer is also important. The largest spray angles were obtained for an atomizer with a diameter of 0.02 m and with the inlet port being placed at an angle to the atomizer axis. Based on the experimental results for various liquids and atomizer designs, a correlation equation describing the spray angle is proposed.

Can We Structure Biomaterials to Spray Well Whilst Maintaining Functionality?

“…Following initial breakup, the sheet fragments contract to form ligaments, which then break up into droplets due to surface tension-driven Rayleigh instability [92]. A number of empirical equations have been developed for important spray parameters (Equation ( 14) [92], Equation ( 15) [98], Equation ( 16) [99] and Equation ( 17) [94]). These include expressions for average droplet size, with median droplet size, 𝐷 , and Sauter mean diameter, SMD, being the most common, and spray angle, 𝜃, which will also influence spray coverage.…”

“…These include expressions for average droplet size, with median droplet size, 𝐷 , and Sauter mean diameter, SMD, being the most common, and spray angle, 𝜃, which will also influence spray coverage. A number of empirical equations have been developed for important spray parameters (Equation ( 14) [92], Equation ( 15) [98], Equation ( 16) [99] and Equation ( 17) [94]). These include expressions for average droplet size, with median droplet size, D 50 , and Sauter mean diameter, SMD, being the most common, and spray angle, θ, which will also influence spray coverage.…”

Low Acyl Gellan as an Excipient to Improve the Sprayability and Mucoadhesion of Iota Carrageenan in a Nasal Spray to Prevent Infection With SARS-CoV-2

“…Important properties of the polymer formulations were mechanistically probed, to understand which affected sprayability. Viscosity, through the dimensionless Reynold's number, is often used in correlations to predict "spray angle, " a parameter which directly affects coverage (45)(46)(47). However, a 1% (w/v) gellan dispersion, which displayed the same viscosity profile as carrageenan, still sprayed significantly better, suggesting viscosity is not a good predictor of spray coverage for these systems.…”

Influence of Spray Nozzle Operating Parameters on the Fogging Process Implemented to Prevent the Spread of SARS-CoV-2 Virus

“…In addition, considerations included the relationship between the geometric pattern of the cone formed by the spray and the ratio of saturation pressure relative to ambient pressure, the occurrence of recirculation phenomena, and secondary formation of small droplets as a result of micro-explosions were identified and described. The changes in the spray angle depending on the rheological properties of the fluid feeding the conical pressure-swirl atomizer were also investigated in [30]. Other studies in this area, such as [31,32], contained results of research concerned with the effect of the nozzle outlet diameter on the spray characteristics.…”