Theoretical basis and method of airflow organization design in enclosed or semi-enclosed space

Abstract

<p indent="0mm">The heating, ventilation, and air conditioning (HVAC) system is currently an important means to create a healthy and comfortable enclosed or semi-enclosed space environment, but the existing HVAC systems not only consume high energy, but also easily cause human health problems, such as sick building syndrome, building-related diseases, and cross infection of infectious diseases. The above phenomenon further shows that the indoor airflow organization (based on the traditional method) formed by the end of the HVAC system is still not perfect, and there are certain blind spots and deficiencies. To solve the problems existing in the design and use of the end of the traditional HVAC system, the inverse design method came into being. The traditional design method is a process of repeated trial and error, while the inverse design method uses an optimization algorithm to inversely determine the airflow organization form and thermophysical boundary (such as the number, shape, and size of air supply inlets and air supply parameters) that meet the needs or objectives by minimizing the objective function. The biggest difference from traditional methods is that the inverse design method can determine the optimal direction vector in each design cycle, while the traditional design method can only keep trial and error. To further clarify the differences between the two types of methods and promote the continuous improvement of inverse design methods, this paper first expounds the scientific problems faced by or to be solved in the construction of indoor environments. The core problem of indoor environment construction is to determine the appropriate airflow organization form and the key scientific problem behind the difficulty in quickly determining the appropriate airflow organization form is that it is difficult to obtain the analytical solution (essence) of the highly nonlinear N-S equation. Then, the classification of airflow organization design methods and their basic principles are introduced in detail. The design performance of the two types of methods is then demonstrated through real-world case results. Although the inverse design method has made great progress in the field of indoor environment construction, the current inverse design method still requires theoretical deduction, program development, and numerical solution, which hinder its popularization and application to a certain extent. Finally, this paper discusses the possible future development directions in the field of indoor environment construction. For example, with the rapid development of human factors engineering, inverse design methods, digital design methods, intelligent control, and other fields, indoor environment design and creation will tend to be diversified and intelligent.