# CFD-Simulink Modeling of the Inflatable Solar Dryer for Drying Paddy Rice
## 5 Conclusions  
This study presents CFD-Simulink models used to simulate and predict the ISD's performance when drying paddy rice. The airflow patterns were successfully investigated across the ISD using a CFD approach via ANSYS Fluent. A good agreement was revealed between the CFD simulation and experimental velocity measurements with an R\({}^{2}\) of 0.78 and RMSE of 0.72 m s\({}^{-1}\). A variation of air velocity from 5 to 0.5 m s\({}^{-1}\) and 0.5 to 0.1 m s\({}^{-1}\) was obtained at the heating and drying area, respectively. A vortex was observed from 3  
Figure 13: Simulated outputs of the ISD drying model using the weather data from the experimental station of the International Rice Research Institute in Los Bános, Laguna, Republic of the Philippines (average 2008–2017); (**a**) drying curves corresponding to the peak harvesting months of the dry season and the rainy seasons and (**b**) drying time obtained for a target MCwb = 14% from each harvest season. to 4 m in the heating area caused by the air conveyance of the axial fans. Moreover, we successfully modeled the drying process of paddy rice using the MATLAB/Simulink. A good agreement between the experimental and the simulated moisture contents of paddy rice (R\({}^{2}>0.82\), RMSE \(<1.4\)\({}^{\circ}\)C, MAPE \(<7.4\%\)) and temperatures (R\({}^{2}>0.73\), RMSE \(<6.6\%\), MAPE \(<6.9\%\)) was achieved. The validated model allowed an accurate assessment of the drying behavior of paddy rice over the rainy and dry seasons to be made. The CFD-Simulink models proved to be an efficient and effective means of simulating and assessing the ISD's performance under different weather conditions. The computational approach used in this study shows great potential as a decision support tool to improve the ISD design. Further investigations should include the mixing effect of paddy rice during drying and the ratio of heating and drying area. Conceptualization, A.S.-R. and J.M. ; methodology, A.S.-R. and J.M. ; software, A.S.-R. and I.R. ; validation, A.S.-R.; formal analysis, A.S.-R., I.R., S.R. and J.M. ; investigation, A.S.-R.; resources, A.S.-R. and J.M. ; data curation, A.S.-R.; writing--original draft preparation, A.S.-R.; writing--review and editing, A.S.-R., I.R., S.R. and J.M. ; visualization, A.S.-R., I.R. and S.R. ; supervision, J.M. ; project administration, A.S.-R.; funding acquisition, J.M. All authors have read and agreed to the published version of the manuscript. This research was made possible through the Global Rice Science Scholarships by International Rice Research Institute (IRRI), grant number 7500 RC000000G4102090, Project Funding for International Agricultural Research Centers, GIZ/BMZ, GIZ Project Number: 10.7860.9-001.00, and the scholarships awarded by Fiat Panis Foundation (Ulm, Germany). Not applicable. The authors would like to thank [PERSON], [PERSON], [PERSON], [PERSON], [PERSON], [PERSON] and [PERSON] from IRRI, [PERSON] for her language editing support, and [PERSON] for assisting in the development of the ISD together with the colleagues from GrainPro Philippines Inc. [PERSON], [PERSON], [PERSON], [PERSON], and [PERSON]. The authors