Design of adaptive makeup air system in negative pressureventilation environment

This project is a biological and safety testing experimental building of the Shanghai Testing Center. Due to the wind pressure imbalance caused by the experimental process exhaust, a series of problems are encountered. After on-site investigation and understanding of the owner’s needs, three relatively simple and feasible renovation plans are proposed, and the advantages and disadvantages of the three plans are compared. The final implementation plan is selected. The entire building of this project is added a negative pressure adaptive makeup air system, and the composition principle, control logic, and control method of the system are presented. According to the operation characteristics of the outdoor air unit in the system, which needs to greatly change the air volume and cooling capacity, the structural characteristics of the traditional direct evaporative outdoor air unit are analysed, the incompatibility of its application to the system is pointed out, and the improvement measures for the unit are proposed. Finally, the design experience of this type of renovation project is shared, which can be used as a reference for the similar engineering design.