Numerical Analysis of the Channel Wheel Fresh Air Ventilator Under Frosting Conditions

摘要

As new equipment, the channel wheel fresh air ventilator has become increasingly popular in recent years. However, when such equipment is operated under low ambient temperature in the freezing area in winter, the formation of frost on the outdoor waste air surface becomes problematic, leading to the degradation of the channel wheel fresh air ventilator's performance or even the shutdown of equipment. Therefore, it is necessary to have a detailed investigation on the operational characteristics of the channel wheel fresh air ventilator under frosting in order to guide its application.This paper first reports on the development of a detailed model for the channel wheel heat exchanger, which is the core part of the channel wheel fresh air ventilator under frosting conditions. The model developed, first seen in open literature, consists of a frosting sub-model and a channel wheel heat exchanger sub-model. This is followed by reporting an evaluation of the operational characteristics of a frosted channel wheel heat exchanger under different ambient conditions using the model developed. These include frost formation on the surface of the channel wheel heat exchanger, and impacts on the operational performance of the channel wheel fresh air ventilator. Furthermore, the interval of defrosting is obtained, which provides the basis for the adoption of effective defrosting measures, and thus increasing the channel wheel fresh air ventilator's energy efficiency and operating reliability.