Experimental and numerical study on thermal performance of an unvented Trombe wall associated with internal thermal fins

Abbassi, Fakhreddine; Dehmani, L.

doi:10.1016/j.enbuild.2015.07.042

Cited by 57 publications

(23 citation statements)

References 25 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…The internal surface structure is part of the important factors to determine the greenhouse microclimate and enhance the thermal performance of the north wall [30,31]. In order to accurately analyze the impact of wall configurations on the internal environment of the greenhouse, the influence of crops on the heat exchange of the north wall structure was neglected [32].…”

Section: Introductionmentioning

confidence: 99%

Effect of internal surface structure of the north wall on Chinese solar greenhouse thermal microclimate based on computational fluid dynamics

Liu

et al. 2020

PLoS ONE

View full text Add to dashboard Cite

Chinese solar greenhouses are unique facility agriculture buildings and widely used in northeastern China, providing a favorable requirement for crop growth. The north wall configurations play an essential role in heat storage and thermal insulation and directly affect the management of the internal environment. This research is devoted to further improve the thermal performance of the greenhouse and explore the potential of the north wall. A mathematical model was designed to investigate the concave-convex wall configurations based on computational fluid dynamics. Four passive heat-storage north walls were analyzed by using the same constituent materials, including a plane wall, a vertical wall, a horizontal wall and an alveolate wall. The numerical model was validated by experimental measurements. The temperature distributions of the north walls were examined and a comparative analysis of the heat storage-release capabilities was carried out. The results showed that the heatstorage capacity of the north wall is affected by the surface structure. Moreover, the critical factor influencing the air temperature is the sum of the heat load released by the wall and the energy increment of greenhouse air. The results suggested that the alveolate wall has preferable thermal accumulation capacity. The concave-convex wall configurations have a wider range of heat transfer performance along the thickness direction, while the plane wall has a superior thermal environment. This study provides a basic theoretical reference to rationally design the internal surface structures of the north wall. OPEN ACCESSCitation: Liu X, Li H, Li Y, Yue X, Tian S, Li T (2020) Effect of internal surface structure of the north wall on Chinese solar greenhouse thermal microclimate based on computational fluid dynamics. PLoS ONE 15(4): e0231316. https://doi.

show abstract

Section: Introductionmentioning

confidence: 99%

Effect of internal surface structure of the north wall on Chinese solar greenhouse thermal microclimate based on computational fluid dynamics

Liu

et al. 2020

PLoS ONE

View full text Add to dashboard Cite

show abstract

“…In this regards, passive thermal energy storage systems (TES) are often proposed because they help to maintain comfort conditions, minimizing the use of mechanical systems and exploiting natural heat energy sources [3], achieving a possible space conditioning energy saving potential of about 10-15% [4]. Among TES, due to the introduction of new materials, new control technologies and new computational and numerical simulation tools, there has been a renaissance of traditional building elements such as passive solar walls [5][6][7][8] and of proposals of different typologies of phase change materials (PCMs), often combined with passive solutions. PCMs are mainly paraffin and binary organic acids as well as inorganic or eutectics, used into building walls, roofs and floors [9][10][11]; they can also be used in passive solar collector-storage wall systems for improving their performance over the whole year [12] or mixed with other materials, mainly mortar [13] and cement [14] to enhance their performance.…”

Section: Introductionmentioning

confidence: 99%

Super-adsorbent polyacrylate under swelling in water for passive solar control of building envelope

et al. 2019

View full text Add to dashboard Cite

Super-adsorbent polymers have the capacity to immobilize huge quantities of water in the form of hydrogel, thanks to their configuration. A commercial sodium polyacrylate (PA) was analysed as such and at different water uptakes, indicated through the weight ratios PA:H 2 O. The hydrogels were prepared using different type of water (tap, distilled and deuterated) and characterized by Infrared and Raman spectroscopic analyses, nuclear magnetic resonance experiments, CHN elemental analysis, measurements of thermal conductivity and diffusivity. All the measurements were done in order to assess applications of PA:H 2 O gels as Thermal Energy Storage systems for improving thermal performances of building envelope through passive solar walls. It has been observed that the behaviour of the hydrogels depends both on temperature and water content. In certain conditions such as low weight ratios, a spontaneous and quick cooling of the hydrogel could be observed. The curves of heat flow and average specific heat (c p) were determined as a function of temperature in order to investigate the states of water in PA hydrogels. When a few water molecules are present, they are mainly and strongly bonded with carboxylate groups. Increasing the amount of water, greater shells of solvation around ionic groups form and water molecules can even interact with neighbouring non-polar hydrocarbon groups. At very high amount of water molecules, they are much more involved into H-bonds among themselves, rather than with PA, so that water pools form into the links of polymeric network. Bulk-like water can freeze and melt. Whatever the amount of water in the hydrogel, its thermal capacity is higher than dry polymer, because the heat can be absorbed by the continuous desorption of water from polymer to bulk-like water (water gel → water liquid), which can evaporate as temperature approaches 100 °C (water gel → water liquid → water vapour).

show abstract

“…It is mostly determined with the use of numerical models that are based either on the finite element method FEM or finite difference method DEM [1][2][3]. In the papers [4,5], the calculation of the efficiency of various types of walls was carried out in field conditions either with the use of speciallyprepared research chambers or experimental houses [6]. The latter ones, in relation to numerical methods, are free of errors that could result from the simplifications adopted in the mathematical description.…”

Section: Introductionmentioning

confidence: 99%

Simulation of modified Trombe wall

Szyszka

2018

E3S Web Conf.

View full text Add to dashboard Cite

Passive systems are becoming increasingly popular among designers, which is reflected in their frequent use in the construction of modern buildings. The prevailing material in façade design is glass which enables i.a. photothermal conversion of solar energy either in the so-called direct systems or in one of a number of the collector-and-storage Trombe wall variants. In order to estimate how the aforementioned passive solutions affect the energy balance of a building, the efficiency of such solutions needs to be determined first. This paper presents the research proposal that would use a simple-structure laboratory simulator. The proposed method is based on the analogy of supplying heat into the TW itself with an internal heat source. In order to simulate the absorption of solar radiation that takes place in the absorber, the heat was produced by the heating cable embedded in such an absorber. The results of tests carried out according to one of the Design of Experiments (DOE) methods enabled the development of an empirical model showing the operation efficiency of the originally modified Trombe wall.

show abstract

Experimental and numerical study on thermal performance of an unvented Trombe wall associated with internal thermal fins

Cited by 57 publications

References 25 publications

Effect of internal surface structure of the north wall on Chinese solar greenhouse thermal microclimate based on computational fluid dynamics

Effect of internal surface structure of the north wall on Chinese solar greenhouse thermal microclimate based on computational fluid dynamics

Super-adsorbent polyacrylate under swelling in water for passive solar control of building envelope

Simulation of modified Trombe wall

Contact Info

Product

Resources

About