The radiant systems come to the fore due to energy saving potential and good integration. The effect of different forms of cold surfaces on human thermal comfort is focused on its application. A novel natural convection-radiant evaporator for heat pumps was developed and its influence on thermal comfort was investigated. A numerical model of the chamber with the evaporator was established and verified with experimental results. Thermal comfort experiments were conducted in a climate chamber and the influence of its asymmetric and uneven cold radiation on the thermal comfort was investigated. Due to the limitation of PMV in uneven radiation situations, the revised predicted mean vote (RPMV) was proposed to assess the thermal comfort in asymmetric and uneven radiation environments based on experimental results. Based on RPMV, the influence of the surface area and temperature of the evaporator on thermal comfort was numerically analyzed. The results indicate that indoor air temperature and relative humidity, RPMV increase with the increase of plate temperature, but decrease with an increase in plate area. The most favourable indoor thermal comfort environment was obtained at an indoor air temperature of 28°C and relative humidity of 50%, which is 2°C higher than traditional air conditioning system.
Global Alliance for Buildings and Construction. International-energy. In: 2020 Global status report: towards a zero-emissions, efficient and resilient buildings and construction sector. Nairobi, Kenya: UN environmental programme, 2020.
2.
LiXYuCWF. China’s building energy efficiency Targets: challenges or opportunities?Indoor Built Environ2012; 21(5): 609–613.
3.
KimJTYuCWF. Sustainable development and requirements for energy efficiency in buildings – the Korean perspectives. Indoor Built Environ2018; 27(6): 734–751.
4.
DelbekeJRunge-MetzgerASlingenbergYWerksmanJ. Chapter 2: the Paris agreement. In: Towards a Climate-Neutral Europe. 1st ed. London: Routledge, 2019, pp. 24–45.
5.
PallonettoFOxizidisSMilanoFFinnD. The effect of time-of-use tariffs on the demand response flexibility of an all-electric smart-grid-ready dwelling. Energy Build2016; 128: 56–67.
6.
ZhaoMKangWBLuoXLYuCWFMengXZGuZL. Performance comparison of capillary mat radiant and floor radiant heating systems assisted by an air source heat pump in a residential building. Indoor Built Environ2017; 26(9): 1292–1304.
7.
XieDTianLLiaoMLYuCWWangHQ. The thermal environment of non-steady state radiation heat transfer with a capillary ceiling radiation cooling system. Indoor Built Environ2019; 28(4): 443–453.
8.
XieDWangCYuCWWangH. Performance of capillary ceiling cooling panel on ceiling surface temperature and indoor thermal environment. Indoor Built Environ2020; 29(6): 881–894.
9.
SongMMaoNXuYDengS. Challenges in, and the development of, building energy saving techniques, illustrated with the example of an air source heat pump. Therm Sci Eng Prog2019; 10: 337–356.
10.
Ab AzisSS. Improving present-day energy savings among green building sector in Malaysia using benefit transfer approach: cooling and lighting loads. Renew Sustain Energy Rev2021; 137: 110570.
11.
ZhaoMGuZLKangWBLiuXZhangLYJinLWZhangQL. Experimental investigation and feasibility analysis on a capillary radiant heating system based on solar and air source heat pump dual heat source. Appl Energy2017; 185: 2094–2105.
12.
SongMDengSMaoNYeX. An experimental study on defrosting performance for an air source heat pump unit with a horizontally installed multi-circuit outdoor coil. Appl Energy2016; 165: 371–382.
13.
StaffellIBrettDBrandonNHawkesA. A review of domestic heat pumps. Energy Environ Sci: EES (Ecotoxicol Environ Saf)2012; 5(11): 9291–9306.
14.
LinBWangZSunHZhuYOuyangQ. Evaluation and comparison of thermal comfort of convective and radiant heating terminals in office buildings. Build Environ2016; 106: 91–102.
15.
GendelisSJakovičsARatnieksJ. Thermal comfort condition assessment in test buildings with different heating/cooling systems and wall envelopes. Energy Proc2017; 132: 153–158.
16.
QinSYWangYAGaoSXuDGCuiXZhaoMJinLW. Heat transfer characteristics of a composite radiant wall under cooling/heating conditions. Indoor Built Environ2019; 29(8): 1155–1168.
17.
CausoneFBaldinFOlesenBWCorgnatiSP. Floor heating and cooling combined with displacement ventilation: possibilities and limitations. Energy Build2010; 42(12): 2338–2352.
ParkHKimDHKimMS. Performance investigation of a cascade heat pump water heating system with a quasi-steady state analysis. Energy2013; 63: 283–294.
20.
VõsaK-VFerrantelliAKullTMKurnitskiJ. Experimental analysis of emission efficiency of parallel and serial connected radiators in EN442 test chamber. Appl Therm Eng2018; 132: 531–544.
21.
ZhangLDongJJiangYDengSHuangS. An experimental study on frosting and defrosting performances of a novel air source heat pump unit with a radiant-convective heating terminal. Energy Build2018; 163: 10–21.
22.
AshminAPipatCSurapongCWipawadeeW. Subjective assessment of thermal comfort by radiant cooling in a tropical hot humid climate. Energy Build2022; 254: 1–13.
23.
DaomingXNianpingL. Thermal performance improvement for the ceiling radiant cooling panel with an inbuilt air gap by the convection shield. Sustain Energy Technol Assessments2021; 44: 1–9.
24.
KhanYKhareVRMathurJBhandariM. Performance evaluation of radiant cooling system integrated with air system under different operational strategies. Energy Build2015; 97: 118–128.
25.
BabiakJOlesenBWPetrasD. Low temperature heating and high temperature cooling-system types and estimation of heating/cooling capacity. 2nd ed.Brussels, Belgium: REHVA (Federation of European Heating, Ventilation and Air-conditioning Associations), 2009.
26.
HaoXZhangGChenYZouSMoschandreasDJ. A combined system of chilled ceiling, displacement ventilation and desiccant dehumidification. Build Environ2007; 42(9): 3298–3308.
27.
TangHLiuX-HJiangY. Theoretical and experimental study of condensation rates on radiant cooling surfaces in humid air. Build Environ2016; 97: 1–10.
28.
FanZHaixinGZhengxuanLGuoqiangZ. A critical review of the research about radiant cooling systems in China. Energy Build2021; 235: 110756.
BejanA. Convection heat transfer. New York: John Wiley & sons, 2013.
31.
YifanWHongliSMengfanDBorongLHengxinZ. Dehumidification-adjustable cooling of radiant cooling terminals based on a flat heat pipe. Build Environ2021; 194: 1–16.
32.
HuanZMingTTingTingJWandongZ. Investigation of thermal comfort performance and optimization of a novel refrigerant-heated radiator. Indoor Built Environ2022; 31(6): 1540–1556.
ISO Standard 7730:2005. Ergonomics of the thermal environment e analytical determination and interpretation of thermal comfort using calculation of the PMV and PPD indices and local thermal comfort criteria. Geneva: International Standards Organization, 2005.
35.
ASHRAE 55–2020. Thermal environment conditions for human occupancy. Atlanta: American Society of Heating Refrigerating and Air-Conditioning Engineers, 2020.
36.
XiangZYunliangLJingsiZLifangYMaohuiL. Radiant asymmetric thermal comfort evaluation for floor cooling system – a field study in office building. Energy Build2022; 260: 1–12.
37.
DoganAKayaciNDemirHSevindirMK. An experimental comparison of radiant wall and ceiling cooling system integrated with ground source heat pump and direct expansion fan coil system in a highly glazed office room. Energy Build2022; 273: 1–16.
38.
TianZLoveJA. A field study of occupant thermal comfort and thermal environments with radiant slab cooling. Build Environ2008; 43(10): 1658–1670.
39.
HumphreysMANicolFJ. The validity of ISO-PMV for predicting comfort votes in every-day thermal environments. Energy Build2002; 34(6): 667–684.
40.
ZhangHYangXZhengWYouSZhengXYeT. The CPMV* for assessing indoor thermal comfort and thermal acceptability under global solar radiation in transparent envelope buildings. Energy Build2020; 225: 110306.
41.
HylandRWWexterA. Formulations for the thermodynamic properties of the saturated phase of H2O from 173.15 K to 473.15 K. Build Eng1983; 89(5): 500–519.
42.
LeeWH. A pressure iteration scheme for two-phase modeling. Multiphase Transport Fundamentals1980; 1: 407–431.
43.
Angle coefficient and average radiation temperature calculation software. Berlin, Germany: Springer, 2023. https://radisantsmartifarmcom/
44.
GB 50736-2012. Design code for heating ventilation and air conditioning of civil buildings. Beijing: China Construction Industry Press, 2012.
45.
Shuzo MurakamiSKKimT. Coupled simulation of convicton, radiation, and HVAC control for attaining a given PMV value. Build Environ2001; 36(6): 701–709.
