ISSN Online: 2379-1748
ISBN Flash Drive: 978-1-56700-483-0
ISBN Online: 978-1-56700-482-3
4th Thermal and Fluids Engineering Conference
Room Air Conditioner Simulation Models for Heat Exchanger Design and Indoor Airflow Control Development
Abstract
Recently, worldwide demand for room air conditioners has increased. The performance and functions required for
these products differ between regions and markets, and therefore, manufacturers need to develop products with a
variety of specifications. Product development will be promoted by repeated experiments where verification can
be measured experimentally, including physical quantities such as temperature and airflow velocity at limited
positions where sensors can be installed. However, it is difficult to estimate the background of the phenomenon
only from experimental data. Therefore, in design practice, quantitative verification using a numerical model
calculation for analysis of experiments is useful. In this paper, we propose two numerical models for (1) a heat
exchanger design and (2) an indoor airflow control technology development in indoor room air conditioner units.
The first is the fin-and-tube heat exchanger model in an indoor unit, which consists of a heat exchanger fin, a fan,
an indoor unit casing, and a refrigerant circuit (tube). This model simulates an airflow pattern on the fin surface
using computational fluid dynamics, and refrigerant flow state in the tube is calculated using a one-dimensional
refrigerant circuit model. The second proposed design is an indoor airflow environment model for calculating
airflow temperature and velocity in rooms equipped with an air conditioner. The room air conditioner can control
the temperature and the velocity distribution of airflow in the room, which influences user thermal comfort by
controlling the direction, temperature, and volume of airflow from the indoor unit outlet. This control is called
airflow control.