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Background Optimizing the geometry of an inhalation exposure chamber (IEC) results in a uniform and stable distribution of the test atmosphere and enables the modeling of its performance. This study was conducted for the first time to optimize and model the performance of an IEC.Methods The current study was performed on the initial design of the ASRA chamber and to optimize and model it. The matrix of experiments was determined by the design expert software (DE7). The mean of particle concentration (MPC) in the respiratory zone of animals as the response variable, and height of the cylindrical section of the chamber, carrier gas density, inlet concentration, and particle aerodynamic diameter ( da ) as independent variables were considered. Experiments were performed by numerical simulation using ANSYS Workbench package. Particle concentration sampling was measured in 40 points at the opening of each holder in CFD-Post software. To determine the optimal range of the chamber's height, the different of MPC among the holders’ opening was investigated by the ANOVA test. The final mathematical model was achieved by analyzing the response variables in DE7.Results Thirty designs in five geometries with different heights were introduced as the matrix of experiments by DE7. The optimal height was obtained 2-2.5 times the radial of the cylindrical section. Analysis of the results suggested a linear model (2FI) with coefficients of recognition higher than 99%. The final model was significant with the presence of the inlet concentration and da . Gas density and height had no significant effect and were removed ( P >0.05).Conclusion The optimization of the geometry of the ASRA chamber resulted in a uniform and stable distribution of the particles and provided an accurate mathematical model to predict the particle concentration in the target zone. |
