A heat transfer parameter at air interfaces in the BLOCK model for building thermal environment

A modelling method for large-scale open spaces orientated toward coordinated control of multiple air-terminal units

“…In a recent study, Yang et al (2020) investigated the heat transfer coefficient to predict the cooling load in a stratified air-conditioning system for a large industrial building. The numerical solution for calculating the heat transfer coefficient was presented and it is highly dependent on the turbulent viscosity, the results were inline with the previous studies (Gao et al 2006;Gao et al 2010). Wang et al (2019) also revealed that the heat transfer coefficient (500 W/(m 2 •°C)) can be reached in the vicinity of the nozzle diffuser, where a strong local turbulent intensity occurs (Hu et al 2022).…”

“…For instance, when the multi-zone control mode is considered, thermal coupling effect or heat transfer between adjacent subzones needs to be treated because there are no clear boundary division or partition which separate the entire zone. Here thermal coupling effect between adjacent subzones is also termed as heat transfer between adjacent zones (Kintner-Meyer 2005), the inter-volume interactions (Negrao 1995), the air exchange rate between two neighboring zones (Wang and Jin 1998), the convective heat transfer between the interior partition surface and room core zone (Awbi and Hatton 1999;Zhang et al 2018b), the heat transfer between air layers (Gao et al 2007;Gao et al 2010), the airflow and heat flux circulate between the inter-connected interfaces (Boukhris et al 2009), the heat transfer between virtual wall (Woradechjumroen et al 2016), the heat transfer on the layered interface/cross-section/intersection area (Wang et al 2019;Yang et al 2020;Hu et al 2022), the dummy wall (Eydner et al 2019), and the air coupling between the sub-zones (Laghmich et al 2022). In the above references, the essence of the physical problem is identical but treated with different terms with respect to different indoor flow mechanisms, which will be illustrated in the following discussion.…”

“…It can be described as a function of the temperature difference and hydraulic diameter. The heat transfer factor between air layers in the vertical direction was calculated with CFD code, and it was related to the laminar and turbulent diffusions with values ranging from 2.0 W/(m 2 •K) to 5.0 W/(m 2 •K) in natural convection and displacement ventilation (Gao et al 2006;Gao et al 2010). However, the heat transfer coefficients in the above studies were empirically or experimentally obtained under the condition of the natural convection.…”

Validation of a transient zonal model to predict the detailed indoor thermal environment: Case of electric radiators and wood stoves

“…where eff k is the effective thermal conductivity of air (which may be higher than the physical thermal conductivity of air, air k , due to turbulence mixing [20,28]…”

“…EQUA has recently proposed a new zonal model [16] that is currently under implementation in IDA ICE. For the room air, this nonpressurized model is similar to the zonal model of Togari [17][18][19][20] already formulated in the early nineties. Regarding the longwave radiation between walls, heat exchange is computed using the radiosity method where view factors are evaluated numerically.…”