On-site measurement of thermal environment and heat transfer analysis in a curling arena

Highlights

• Introduce a large space curling arena with ETFE membrane structure.

• Carry out field measurement for thermal environment in curling arena.

• Calculate the thermal load of ice and the longwave radiation contributes 56% of the total heat.

• Cavity ventilation helps to reduce 8.8% refrigeration load.

Abstract

Maintaining a stable ice pad and indoor thermal environment satisfying requirements usually consumes high energy consumption in ice arenas. In this paper, a curling arena with ethylene tetra fluoro ethylene (ETFE) membrane structure is taken as an example to analyze the refrigeration load. Field tests for thermal environment are firstly carried out in this arena. Sources of refrigeration load are determined and possible reducing approaches are proposed to lower the energy consumption for ice making issue. It’s indicated that average refrigeration load of the curling ice is 152.8W/m², among which long wave radiation contributes 55.5%. The ceiling temperature could reach as high as 26 °C, contributing more than 70% of the longwave radiation. It’s then noted that cavity ventilation could be a special method to lower the roof temperature on basis of avoiding condensation, reducing the refrigeration load by 7% for this special building with ETFE membrane envelope. It’s hoped that the current research will be beneficial for the design and operation of an ice competition circumstance.

Introduction

Winter sports have developed rapidly around the world in recent years, while plenty of indoor ice arenas are under construction. In China, there were over 200 assorted ice arenas put into use by the end of 2015, and 500 new ice arena projects will help to satisfy 300 million people’s demands by the end of 2022 [1]. Meanwhile, energy consumption of ice arenas is extremely high [2]. For example, research in Canadian shows that approximately 3500 GWh of electricity is used for ice rinks annually, while they generate 5 × 10⁵ tons of gases contributing to the greenhouse effect [3]. The average annual energy consumption of a single ice field in Canada is 1500 MWh, and the maximum could reach 2400 MWh [4]. Similar results of 52 ice rinks in Sweden concluded that the average energy consumption was about 1185 MWh annually for each arena [5]. Moreover, the refrigeration system accounts for 35%–75% of the total energy usage in Sweden ice rinks. According to statistics, the annual operating power consumption per unit area of indoor ice making and air conditioning system is 300–700 kWh/(m²·a) [6,7], which is 1.7∼3.9 times as high as the average value in office buildings. Magyar [8] also indicated that the refrigeration load accounts for 43% among the total energy consumption in his research. It is necessary to do detailed analysis in the characteristics of ice rinks to decrease the energy consumption, especially the refrigeration load [9].

For different kinds of ice arenas (entertainment [10], ordinary competition [11], professional competitions [12,13]) and different athletic categories [14], the stipulated parameters are different on the ice and surrounding thermal environment. But the process of making and maintaining ice is basically the same, which could be divided into making ice, maintaining ice and resurfacing ice [15]. The ice pad stays stable maintaining at most time, during which the refrigeration is concerned. It carries out the heat exchange process with refrigerant and surrounding environment simultaneously. For the heat transfer inside the ice, Gabriel [16] presented the mathematical and simulated models for the heat transfer in ice rink floor, with a refrigeration load of 135W/m². As for the heat transfer outside the ice, the cooling load characteristics differ in different ice rinks [17]. Research in Montreal shows the ceiling temperature which is affected by the external temperature and solar radiation contributes most to the refrigeration load [3]. Similar conclusions can be also found in Ferrantelli’s studies [18]. However, energy research of an ice rink in Turkey [19] shows the most proportion of load comes from convective heat transfer between the ice and surrounding air, which is similar in Bellache’s research [20]. This contribution is related to the parameters controlled by the air conditioning system near the ice surface. The basic ice rink parameter studied by recent literatures for ice load and energy consumption are listed in Table 1. Based on extensive research, scholars summarize the energy saving operation strategies to reduce the refrigeration load, such as using low emissivity ceiling, controlling both the temperature above ice surface and the flow of secondary refrigerant circulation pump [21]. The researchers also studied the interaction between ice and spectators. The main research methods are calculation, including Computational Fluid Dynamics (CFD) or other mathematical calculation, and field test approach.

In summary, previous literatures mainly focused on the research of ice hockey, skating and other entertainment arenas as shown in Table 1, but lack of research on curling arena. The requirements of the curling ice and air are different from those of other arenas [13], especially for strict professional curling rinks. Meanwhile, the scale of ice rinks under research is similar at around 11 m, and most of them use conventional building structures. However, there still lacks research on the ice in arenas higher than 20 m.

The target building of this paper is a 36 m height indoor curling arena. The large space may bring changes to the heat transfer on ice at the bottom. It is covered by the double ethylene tetra fluoro ethylene (ETFE) membrane, which has good mechanical properties, high transparency and good fire resistance [22]. It has been gradually applied in stadium building envelope materials in recent years, such as the National Aquatic Center [23] and Munich Allianz Stadium [24]. It might lead to significant changes in the thermal environment of the building, and the characteristics of the ice load composition will change.

This paper conducted on-site measurement in the target ice arena, where thermal environment and refrigeration load of the curling ground are investigated according to the on-site measured results. Meanwhile, load sources and influential factors are emphasized, especially for the long-wave radiation. In view of the existing load characteristics, possible methods are proposed to reduce the energy consumption. The current research will be beneficial for the design and operation of an ice competition circumstance.