The Research Of Dedicated Outdoor Air System With Ceiling Radiant Cooling Panels

The dedicated outdoor air system with ceiling radiant cooling panels was first proposed by the scholars of United States, it is mainly directed against the ceiling radiant cooling panels and displacement Ventilation system in North America to promote the condensation encountered, ceiling panels'cooling capacity and a one-time investment for the issue.Using an dedicated outdoor air system will not only improve the cold shoulder the load capacity and eliminate all latent heat load of the room, maintain low relative humidity, lower ceiling panels surface condensation risks, and because the air-conditioning systems needs no return air, it has greatly improved the safety, health and comfort of the architecture environment.This thesis gives a comprehensive introduction and analysis about the dedicated outdoor air system with ceiling radiant cooling panels, including their advantages and disadvantages, the system's components, design, and a new style of the dedicated outdoor air system, and the system design process of calculation and annotations through an example. By the radiation theoretical analysis, the heat transfer calculation of the ceiling radiant cooling panels is analyzed, and a mathematical model for heat transfer is established. The heat transfer of ceiling radiant cooling panels mainly includes two aspects: convective heat transfer with indoor air; radiation heat transfer with internal sides of retaining structures and the surfaces of other objects. Moreover, the calculation of the heat transfer of ceiling radiant cooling panels in an actual project is introduced, including calculation of heat transfer between the ceiling radiant cooling panels and human body, and surfaces of retaining structures.In this thesis, the method of thermal comfort assessment about the ceiling radiant cooling panels with dedicated outdoor air system is introduced and analyzed. By utilizing the method of numerical simulation, the indoor thermal environment is simulated in a typical office with the ceiling radiant cooling panels with dedicated outdoor air system, including indoor temperature field, velocity field, vertical temperature gradient. And the EDT (Effective Draft Temperature) of typical points in the field are calculated, furthermore ADPI (Air Diffusion Performance Index) of those points are also calculated.