scholarly journals A method of cooling capacity enhancement of ceiling panel

2019 ◽  
Vol 116 ◽  
pp. 00099
Author(s):  
Janusz Wojtkowiak ◽  
Łukasz Amanowicz

The cooling energy demand in the buildings is quite large nowadays and it will increase rapidly in the near future. Therefore, capacity of existing cooling devices must be increased. In this paper surface corrugation as a method of capacity enhancement of ceiling panels is theoretically investigated. A subject of the analysis is the effect of corrugation length L and corrugation angle β on the panel’s cooling capacity. It is shown that in the typical conditions the cooling power of the panel with modified surface can achieve even 153 W/m2 and it is about up to 2.5 times higher than the power of a reference panel with flat surface.

2021 ◽  
Vol 13 (13) ◽  
pp. 7251
Author(s):  
Mushk Bughio ◽  
Muhammad Shoaib Khan ◽  
Waqas Ahmed Mahar ◽  
Thorsten Schuetze

Electric appliances for cooling and lighting are responsible for most of the increase in electricity consumption in Karachi, Pakistan. This study aims to investigate the impact of passive energy efficiency measures (PEEMs) on the potential reduction of indoor temperature and cooling energy demand of an architectural campus building (ACB) in Karachi, Pakistan. PEEMs focus on the building envelope’s design and construction, which is a key factor of influence on a building’s cooling energy demand. The existing architectural campus building was modeled using the building information modeling (BIM) software Autodesk Revit. Data related to the electricity consumption for cooling, building masses, occupancy conditions, utility bills, energy use intensity, as well as space types, were collected and analyzed to develop a virtual ACB model. The utility bill data were used to calibrate the DesignBuilder and EnergyPlus base case models of the existing ACB. The cooling energy demand was compared with different alternative building envelope compositions applied as PEEMs in the renovation of the existing exemplary ACB. Finally, cooling energy demand reduction potentials and the related potential electricity demand savings were determined. The quantification of the cooling energy demand facilitates the definition of the building’s electricity consumption benchmarks for cooling with specific technologies.


Energies ◽  
2021 ◽  
Vol 14 (9) ◽  
pp. 2703
Author(s):  
Robert Sekret ◽  
Przemysław Starzec

The paper presents the investigation of a prototype cold accumulator using water–ice latent heat for the cold storage process. The concept of the cold accumulator was based on a 200-L-capacity cylindrical storage tank in which spherical capsules filled with water were placed. Beds of polypropylene capsules with diameters of 80 mm, 70 mm, and 60 mm were used in the tests. The cold accumulator operated with a water–air heat pump. Based on the test results, the following parameters were calculated: the cooling capacity, cooling power, energy efficiency of the cold storage, and energy efficiency ratio (EER) of the accumulator. The obtained measurement results were described with mathematical relationships (allowing for measurement error) using criterial numbers and the developed “Research Stand Factor Number” (RSFN) index. It has been found that, for the prototype cold accumulator under investigation, the maximum values of the cooling capacity (17 kWh or 85.3 kWh per cubic meter of the accumulator), energy efficiency (0.99), and EER (4.8) occur for an RSFN of 144·10−4. The optimal conditions for the operation of the prototype cold accumulator were the closest to laboratory tests conducted for a bed with capsules with a diameter of 70 mm and a mass flow of the water–glycol mixture flowing between the accumulator and the heat pump of 0.084 kg/s. During the tests, no significant problems with the operation of the prototype cold accumulator were found.


2020 ◽  
Vol 15 (3) ◽  
Author(s):  
Afshar Alihosseini

AbstractCurrently, air separation units (ASUs) have become very important in various industries, particularly oil and petrochemical industries which provide feed and utility services (oxygen, nitrogen, etc.). In this study, a new industrial ASU was evaluated by collecting operational and process information needed by the simulator by means of HYSYS software (ASPEN-ONE). The results obtained from this simulator were analyzed by ASU data and its error rate was calculated. In this research, the simulation of ASU performance was done in the presence of an expansion turbine in order to provide pressure inside the air distillation tower. Likewise, the cooling capacity of the cooling compartment and the data were analysed. The results indicated that expansion turbine is costly effective. Notably, it not only reduces the energy needed to compress air and supply power of the equipment, but also provides more cooling power and reduces air temperature. Moreover, turbines also increase the concentration of lighter gas products, namely nitrogen.


2021 ◽  
pp. 0887302X2110530
Author(s):  
Lennart Teunissen ◽  
Emiel Janssen ◽  
Joost Schootstra ◽  
Linda Plaude ◽  
Kaspar Jansen

Eleven phase change materials (PCMs) for cooling humans in heat-stressed conditions were evaluated for their cooling characteristics. Effects of packaging material and segmentation were also investigated. Sample packs with a different type PCM (water- and oil-based PCMs, cooling gels, inorganic salts) or different packaging (aluminum, TPU, TPU + neoprene) were investigated on a hotplate. Cooling capacity, duration, and power were determined. Secondly, a PCM pack with hexagon compartments was compared to an unsegmented version with similar content. Cooling power decreased whereas cooling duration increased with increasing melting temperature. The water-based PCMs showed a >2x higher cooling power than other PCMs, but were relatively short-lived. The flexible gels and salts did not demonstrate a phase change plateau in cooling power, compromising their cooling potential. Using a TPU or aluminum packaging was indifferent. Adding neoprene considerably extended cooling duration, while decreasing power. Segmentation has practical benefits, but substantially lowered contact area and therefore cooling power.


Energies ◽  
2019 ◽  
Vol 12 (4) ◽  
pp. 693 ◽  
Author(s):  
Mehdi Taebnia ◽  
Sander Toomla ◽  
Lauri Leppä ◽  
Jarek Kurnitski

Indoor ice rink arenas are among the foremost consumers of energy within building sector due to their exclusive indoor conditions. A single ice rink arena may consume energy of up to 3500 MWh annually, indicating the potential for energy saving. The cooling effect of the ice pad, which is the main source for heat loss, causes a vertical indoor air temperature gradient. The objective of the present study is twofold: (i) to study vertical temperature stratification of indoor air, and how it impacts on heat load toward the ice pad; (ii) to investigate the energy performance of air handling units (AHU), as well as the effects of various AHU layouts on ice rinks’ energy consumption. To this end, six AHU configurations with different air-distribution solutions are presented, based on existing arenas in Finland. The results of the study verify that cooling energy demand can significantly be reduced by 38 percent if indoor temperature gradient approaches 1 °C/m. This is implemented through air distribution solutions. Moreover, the cooling energy demand for dehumidification is decreased to 59.5 percent through precisely planning the AHU layout, particularly at the cooling coil and heat recovery sections. The study reveals that a more customized air distribution results in less stratified indoor air temperature.


Author(s):  
Sudheer Awasthi ◽  
Naveen Adhikari

In spite of huge hydro-electricity potential, Nepal still relies on fossil fuel to meet its energy demand. However, as the pace of hydroelectricity generation gets momentum in recent years, there are concerns about the excess supply of hydroelectricity in the domestic market in the near future. In this context, this paper examines the potential substitution of conventional fuels by the hydroelectricity in Nepal. Using translog production function, this paper calculates the elasticity of substitution between hydroelectricity, coal, gas, petrol, diesel, and kerosene for the period of 1980 to 2016. Our findings suggest that all the fuels except kerosene are positively associated with economic growth during the study period, and the output elasticity of hydroelectricity is found be largest among these sources of energy. The findings also suggest that hydroelectricity has the potential for substitute other conventional fuels if the share of hydroelectricity is increased in the energy consumption composition. While there is not a huge variation in the elasticity of substitution between hydroelectricity and other fuels, the hydroelectricity has relatively higher potential to substitute coal followed by petrol, diesel, kerosene, and gas. The findings of the paper are supportive of the hypothesis that Nepal could potentially absorb the hydroelectricity generated in near future if incentive mechanisms are initiated that allow substitution of conventional fossil fuels by the hydroelectricity.


Author(s):  
Sławomir Rabczak ◽  
Maria Bukowska ◽  
Danuta Proszak-Miąsik ◽  
Krzysztof Nowak

Sign in / Sign up

Export Citation Format

Share Document