A Review of Studies on Heat Transfer in Buildings with Radiant Cooling Systems

Abstract

Due to their benefits in interior thermal comfort, energy saving, and noise reduction, radiant cooling systems have received wide attention. Radiant cooling systems can be viewed as a part of buildings’ maintenance structure and a component of cooling systems, depending on their construction. This article reviews studies on heat exchange in rooms utilizing radiant cooling systems, including research on conduction in radiant system structures, system cooling loads, cooling capacity, heat transfer coefficients of cooling surfaces, buildings’ thermal performance, and radiant system control strategy, with the goal of maximizing the benefits of energy conservation. Few studies have examined how radiant cooling systems interact with the indoor environment; instead, earlier research has focused on the thermal performance of radiant cooling systems themselves. Although several investigations have noted variations between the operating dynamics of radiant systems and conventional air conditioning systems, the cause has not yet been identified and quantified. According to heat transfer theory, the authors suggest that additional research on the performance of radiant systems should consider the thermal properties of inactive surfaces and that buildings’ thermal inertia should be used to coordinate radiant system operation.

Thermal Environment Analysis and Optimization for Large Space Buildings with Radiant Cooling Floors: A Case Study of Xianyang International Airport

“…This operation is generally in a non-steady state, and depends on many parameters [23,24]. As previous research has indicated, parameters like pipe diameter, material, pipe depth and spacing, supply water temperature, and flow rate influence the cooling capacity of radiant cooling systems [21]. For radiant systems in use, the cooling capacity can be adjusted by changing the water temperature or water flow rate, ultimately influencing the cooling surface temperature.…”

“…With regard to the combined system discussed in this study, several parameters can be adjusted to meet cooling demand, such as the supply air temperature of the ventilation systems, the supply water temperature of cooling floors, etc. Different control strategies may lead to different levels of energy use, even while maintaining the same comfort level, as radiant floors primarily exchange heat through radiation, while air ventilation systems exchange heat by convection [21]. However, there has been limited research performed on indoor environments in large spaces with regard to radiant floor/displacement ventilation system combinations under different weather conditions and different control strategies.…”

“…Figure1. The process of heat transfer and cooling load formation in a space with a combined radiant cooling and air conditioning system[21].…”

A Comparative Analysis of Machine Learning Algorithms in Predicting the Performance of a Combined Radiant Floor and Fan Coil Cooling System

“…Thus, many studies have been conducted on the optimization of their energy efficiency [5][6][7][8]. It has been shown that radiant cooling systems are able to significantly reduce energy consumption compared with conventional convective air conditioning systems [9][10][11].…”