Single-Coil Twin-Fan Air-Conditioning and Air-Distribution System—Toward Development of a Mathematical Model of the Compartmented Coil

Abstract

A new air-conditioning and air-distribution system, called the single-coil twin-fan system, that provides both energy efficiency and good indoor air quality was developed. It employs a unique compartmented cooling and dehumidifying coil that is fundamental in realizing the significant benefits of the system by being able to treat the outdoor air and the recirculated airstreams separately. In view of the distinctly different features of the compartmented coil, the performance prediction of such coils would have to be approached from first principles, which involves the determination of the fundamental heat and mass transfer coefficients. This paper establishes the need for a new mathematical model for the compartmented coil, outlines the underlying assumptions of classical models, and describes the formulation of an improved model. It presents a unique experimental method for determining the complex fin surface temperatures that constitute the major enhancements to the model development. Finally, the newly developed mathematical model is validated with experimental results.