## 5 Conclusions  
The spread of COVID-19 has caused severe impacts in China and many other countries around the world. Different design schemes of the COVID-19 temporary hospitals need to be quantitatively evaluated and optimized in a short time span, which calls for a high-efficiency and low-cost methods to simulate the dispersion of the exhausted harmful air from temporary hospitals. To address this problem, a high-efficiency simulation framework based on the FDS was proposed in this study. The proposed  
Figure 22: Ratios of the simulated maximum instantaneous concentrations near the fresh-air intakes in the final design phase to those in the transition design phase. simulation framework adapts to building information with different LODs in various design phases of the temporary hospital and has been applied in the design of the Wuhan Huoshenshan Hospital, the first temporary hospital built in China for centralized treatment of the COVID-19 patients. The main conclusions of this study are as follows:  
1. [leftmargin=*]
2. Powered by the FDSGenerator program, the open-source feature of FDS, and the cloud computing technology, the proposed simulation method can assist engineers in quickly investigating the spatial distribution of the exhausted harmful air from temporary hospitals, thereby enabling designers to complete the HVAC design in a short time. The high-efficiency simulation framework and the corresponding case study of the Wuhan Huoshenshan Hospital can provide a reference for the HVAC design and overall planning of similar hospitals in China and other affected countries. 3. In terms of the numerical simulation of pollutant dispersion around buildings, compared with the commercial CFD software Fluent, FDS can significantly improve the modeling and CFD computation efficiency while ensuring accuracy. 4. According to the simulation results of the Wuhan Huoshenshan Hospital, neither the fresh-air intakes nor the surrounding buildings would be polluted by the harmful air discharged from the air outlets of the hospital. At present, COVID-19 is still rapidly spreading in many countries around the world. The proposed high-efficiency simulation framework and the corresponding case study of the Wuhan Huoshenshan Hospital can provide a reference for the design and overall planning of similar hospitals in some affected countries. Furthermore, even not in the COVID-19 era, the proposed simulation method can also be a useful design tool for some infectious disease hospitals. Conceptualization, X.L. ; data curation, D.G. and X.L. ; formal analysis, D.G., Z.Z., and P.Z. ; funding acquisition, X.L. ; investigation, D.G. ; methodology, D.G. and Z.Z. ; project administration, X.L. ; resources, X.L. ; software, X.L. ; supervision, X.L. ; validation, D.G. and Z.Z. ; visualization, D.G. ; writing--original draft, D.G. ; and writing--review and editing, L.X., Z.X., and X.L. All authors have read and agreed to the published version of the manuscript. This research was funded by the National Natural Science Foundation of China (grant number U1709212) and the Tencent Foundation through the xplorer prize. The authors would like to thank CITIC General Institute of Architectural Design and Research Co., Ltd. for providing the design information of the Wuhan Huoshenshan Hospital. The authors also appreciate Beijing PARATERA Tech Co., Ltd. for providing the computational hardware and software that were used in this work. The authors declare no conflict of interest. The funders had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript; or in the decision to publish the results. * _[PERSON] et al. (2015)_ [PERSON]; [PERSON]; [PERSON]; [PERSON]. Near-field pollutant dispersion in an actual urban area: Analysis of the mass transport mechanism by high-resolution Large Eddy Simulations. _Comput. Fluids_**2015**, _114_, 151-162. [CrossRef]
* [PERSON] and [PERSON] (2002) [PERSON]; [PERSON] On the escape of pollutants from urban street canyons. _Atmos.