21. Numerical Analysis of Air Flow Around a Hot Water Radiator for Its Structure Improvement

Hot water radiators are widely used for indoor heating mainly in North China and a large quantity of fossil fuels are needed for heating energy use every year. Therefore, it is important to analyze thoroughly the characteristic of this type of radiators in order to reduce energy use and associated carbon emissions in the building sector of China. Improper design of heating radiator results in excessive energy consumption with uneven temperature distribution, and dust mark on the wall may occur. For the purpose of energy saving and carbon emission reduction, the numerical simulation of the heat transfer and air flow around radiators within heating rooms is necessary to understand the reason for this dust mark and furthermore to modify the radiator configuration. In this paper, the two-dimensional and three-dimensional models were set up, in which both the Navier–Stokes equations and energy equations were solved by using FLUENT^® software, with the standard κ-ε turbulence model and SIMPLE algorithm. By analysis of the indoor air velocity field and the distribution of temperature field, the influence on fine dust particles distribution due to air flow around the radiator was discussed to explain the cause of dust formation. Then, the external structure of the radiator was modified to change the flow field patterns using numerical simulation, and consequently to minimize the dust formation for energy reduction and improve indoor beautiful appearance.