scholarly journals Analysis of heat exchanger in an air handling unit – A case study

2021 ◽  
Vol 321 ◽  
pp. 04018
Author(s):  
Marek Borowski ◽  
Klaudia Zwolińska ◽  
Marcin Czerwiński

Ventilation plays an important role in providing comfortable conditions for users and is also one of the most energy-consuming systems in the building. Due to successive regulations aimed at reducing the energy load of buildings towards zero-energy buildings, energy recovery systems in air handling units have become an indispensable element. The high effectiveness of the entire system guarantees a reduction in energy demand. At very low or very high external temperatures, appropriate comfort conditions are provided by additional heaters or coolers. The subject of the paper is a ventilation system in a hotel located in southern Poland. The building is a faithful reconstruction of the historical saltworks adapted for the needs of the hotel. The air handling unit equipped with a rotary exchanger supplies air to hotel rooms located on two floors. The analysis includes the effectiveness of the air-handling unit operation under various external conditions, as well as the temperature changes during heat exchange. The results show the actual operation of the air-handling unit, which is particularly important in terms of reducing the energy consumption of the hotel.

2021 ◽  
Vol 3 (2) ◽  
pp. 7-13
Author(s):  
Jaya Prathab T. Arumugam ◽  
Kamran Shavarebi

The Relative Humidity in a Catheter Laboratory is desirous to be controlled within a range of 30 to 65% RH. A maximum Relative Humidity (RH) fluctuation of up to 70% is tolerated. A case study is presented whereby a high RH of up to 80% RH has been recorded in the examination room of a Catheter Laboratory (CathLab) in a local Hospital. The conditioned air to the CathLab is supplied through an existing dedicated Chilled Water Air Handling Unit. Two (2) solutions were considered and the technical and commercial comparisons carried out. The first option is an inline dehumidifier system and the second option is to install a portable standalone dehumidifier inside the CathLab examination room. Solutions to address the high Relative Humidity have to be carefully considered as the introduction of in-line dehumidifiers contribute to higher energy consumption. The latter was selected based on commercial reasons. Three (3) weeks of RH monitoring via the building’s Integrated Building Management System (IBMS) was carried out. The readings measured show a drastic reduction in RH to a mean of about 60% RH which meets the end user’s requirement. The cost for the second option was also found to be much lower at about 10% of the first option.


Author(s):  
Sebastian Jachimowicz ◽  
Katarzyna Gładyszewska-Fiedoruk

The elaboration is the study is to examine the difference in the sound level in the air handling units made by the same producer. These units are of the same design parameters and components, and supply air and exhaust air. The only difference is mounted engines. Tested air handling units are equipped with an engine type EC, and traditional direct drive, controlled by an converter. Sound level measurements were carried out in the ducts supply air ventilation system at a distance of 1 m from the air handling unit and for the unit at a distance of 2 m from the inspection door of the fan section of the supply, with 3 settings efficiency of units 30%, 60% and 90%. Tested headquarters are located inside the building. Excessive noise has a negative effect on the human body, resulting in fatigue, difficulty in learning and concentration, impaired orientation, annoyance, increase in blood pressure, headaches, dizziness, and in the worst case of temporary or permanent hearing loss. For this reason it is very important to protect against noise. Therefore, it was these studies.


2019 ◽  
Vol 6 (1) ◽  
pp. 40-49
Author(s):  
Teresa Paiva

Background: The theoretical background of this article is on the model developed of knowledge transfer between universities and the industry in order to access the best practices and adapt to the study case in question regarding the model of promoting and manage innovation within the universities that best contribute with solution and projects to the business field. Objective: The development of a knowledge transfer model is the main goal of this article, supported in the best practices known and, also, to reflect in the main measurement definitions to evaluate the High Education Institution performance in this area. Methods: The method for this article development is the case study method because it allows the fully understanding of the dynamics present within a single setting, and the subject examined to comprehend what is being done and what the dynamics mean. The case study does not have a data collection method, as it is a research that may rely on multiple sources of evidence and data which should be converged. Results: Since it’s a case study this article present a fully description of the model proposed and implemented for the knowledge transfer process of the institution. Conclusion: Still in a discussion phase, this article presents as conclusions some questions and difficulties that could be pointed out, as well as some good perspectives of performed activity developed.


Author(s):  
Dr. Vidhyasri M ◽  
Dr. S. M. Pasha

Introduction: This is the case report of child who was diagnosed with LCA reported with complaints of large-amplitude, slow-frequency, roving nystagmus, frequent tendency to press on his eyes, enopthalmos, with completely normal ophthalmoscopic examination with normal appearing optic nerve and retina and has a non recordable ERG; considering this condition under the lines of Vataja Nanatmaja Vyadhi treatment was structured to render effective visual rehabilitation which showed marked results. Methods: 4 years old male child who was diagnosed with lebers congenital amaurosis was brought by his parents to Eye OPD, GAMC, Bengaluru. The presentation of this case includes bibliographic review of the subject, presentation of a clinical case and description of the importance of Ayurvedic prespective of handling of these patients. Results: The child showed improvement in fixing for light and also nystagmus showed marked improvement and there were considerable behavioural changes observed. Discussion: It is important to deepen the environment of the disease to know the possible implications in Ayurvedic management, recognize the magnitude of visual disability that our patient presents for the establishment of the treatment plan and provide an integral care of excellence in an interdisciplinary way in favor of visual rehabilitation of our patients and also help to restore quality of life with no potential risks of side effects.


Molecules ◽  
2021 ◽  
Vol 26 (6) ◽  
pp. 1672
Author(s):  
Ysadora A. Mirabelli-Montan ◽  
Matteo Marangon ◽  
Antonio Graça ◽  
Christine M. Mayr Marangon ◽  
Kerry L. Wilkinson

Smoke taint has become a prominent issue for the global wine industry as climate change continues to impact the length and extremity of fire seasons around the world. Although the issue has prompted a surge in research on the subject in recent years, no singular solution has yet been identified that is capable of maintaining the quality of wine made from smoke-affected grapes. In this review, we summarize the main research on smoke taint, the key discoveries, as well as the prevailing uncertainties. We also examine methods for mitigating smoke taint in the vineyard, in the winery, and post production. We assess the effectiveness of remediation methods (proposed and actual) based on available research. Our findings are in agreement with previous studies, suggesting that the most viable remedies for smoke taint are still the commercially available activated carbon fining and reverse osmosis treatments, but that the quality of the final treated wines is fundamentally dependent on the initial severity of the taint. In this review, suggestions for future studies are introduced for improving our understanding of methods that have thus far only been preliminarily investigated. We select regions that have already been subjected to severe wildfires, and therefore subjected to smoke taint (particularly Australia and California) as a case study to inform other wine-producing countries that will likely be impacted in the future and suggest specific data collection and policy implementation actions that should be taken, even in countries that have not yet been impacted by smoke taint. Ultimately, we streamline the available information on the topic of smoke taint, apply it to a global perspective that considers the various stakeholders involved, and provide a launching point for further research on the topic.


Energies ◽  
2020 ◽  
Vol 14 (1) ◽  
pp. 156
Author(s):  
Paige Wenbin Tien ◽  
Shuangyu Wei ◽  
John Calautit

Because of extensive variations in occupancy patterns around office space environments and their use of electrical equipment, accurate occupants’ behaviour detection is valuable for reducing the building energy demand and carbon emissions. Using the collected occupancy information, building energy management system can automatically adjust the operation of heating, ventilation and air-conditioning (HVAC) systems to meet the actual demands in different conditioned spaces in real-time. Existing and commonly used ‘fixed’ schedules for HVAC systems are not sufficient and cannot adjust based on the dynamic changes in building environments. This study proposes a vision-based occupancy and equipment usage detection method based on deep learning for demand-driven control systems. A model based on region-based convolutional neural network (R-CNN) was developed, trained and deployed to a camera for real-time detection of occupancy activities and equipment usage. Experiments tests within a case study office room suggested an overall accuracy of 97.32% and 80.80%. In order to predict the energy savings that can be attained using the proposed approach, the case study building was simulated. The simulation results revealed that the heat gains could be over or under predicted when using static or fixed profiles. Based on the set conditions, the equipment and occupancy gains were 65.75% and 32.74% lower when using the deep learning approach. Overall, the study showed the capabilities of the proposed approach in detecting and recognising multiple occupants’ activities and equipment usage and providing an alternative to estimate the internal heat emissions.


2021 ◽  
Vol 13 (3) ◽  
pp. 1505
Author(s):  
Ignacio Menéndez Pidal ◽  
Jose Antonio Mancebo Piqueras ◽  
Eugenio Sanz Pérez ◽  
Clemente Sáenz Sanz

Many of the large number of underground works constructed or under construction in recent years are in unfavorable terrains facing unusual situations and construction conditions. This is the case of the subject under study in this paper: a tunnel excavated in evaporitic rocks that experienced significant karstification problems very quickly over time. As a result of this situation, the causes that may underlie this rapid karstification are investigated and a novel methodology is presented in civil engineering where the use of saturation indices for the different mineral specimens present has been crucial. The drainage of the rock massif of El Regajal (Madrid-Toledo, Spain, in the Madrid-Valencia high-speed train line) was studied and permitted the in-situ study of the hydrogeochemical evolution of water flow in the Miocene evaporitic materials of the Tajo Basin as a full-scale testing laboratory, that are conforms as a whole, a single aquifer. The work provides a novel methodology based on the calculation of activities through the hydrogeochemical study of water samples in different piezometers, estimating the saturation index of different saline materials and the dissolution capacity of the brine, which is surprisingly very high despite the high electrical conductivity. The circulating brine appears unsaturated with respect to thenardite, mirabilite, epsomite, glauberite, and halite. The alteration of the underground flow and the consequent renewal of the water of the aquifer by the infiltration water of rain and irrigation is the cause of the hydrogeochemical imbalance and the modification of the characteristics of the massif. These modifications include very important loss of material by dissolution, altering the resistance of the terrain and the increase of the porosity. Simultaneously, different expansive and recrystallization processes that decrease the porosity of the massif were identified in the present work. The hydrogeochemical study allows the evolution of these phenomena to be followed over time, and this, in turn, may facilitate the implementation of preventive works in civil engineering.


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