Diseño de un controlador para sistemas de refrigeración aplicando índice de confort térmico simplificado

This work, the objective is to study a simplified thermal comfort index and apply it to a model of a building with a cooling system in order to check if this simplified comfort index works as a substitute for the standardized index that is indicated in international standards and lead to the decrease in the use of six input variables to only two, which would present a reduction in the number of measuring instruments to be used in real applications. This application presents a Derivative Integral Proportional Controller (PID) to calculate the temperature that satisfies the conditions so that inside the building a comfortable environment is maintained following the scales of the comfort indices. Comparisons of temperatures, thermal comfort scales and percentage of dissatisfied people in both models are required to obtain a validation. The programming of the building’s mathematical models as of the simplified and standard thermal comfort indices is planned to demonstrate based on block diagrams using the software Matlab® on its Simulink platform.

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Thermal comfort index in lactating cows in an adapted free-stall facility

Revista Agrogeoambiental ◽

10.18406/2316-1817v11n420191371 ◽

2020 ◽

Vol 11 (4) ◽

Author(s):

João Marcos de Carvalho Vasconcelos ◽

Sindynara Ferreira ◽

Elisa De Souza Junqueira Rezende ◽

José Luiz de Andrade Rezende Pereira

Keyword(s):

Body Temperature ◽

Relative Humidity ◽

Thermal Comfort ◽

Experimental Period ◽

Temporal Variations ◽

Holstein Cattle ◽

Black And White ◽

Comfort Index ◽

Lactating Cows ◽

Comfort Indices

This study was conducted to investigate the thermoregulation of Holstein cattle in an adapted free-stall facility at IFSULDEMINAS, Campus Inconfidentes, by measuring thermal comfort indices. The experimental period was from the end of December 2012 to the start of January 2013, in a total of 16 days. 12 multiparous, lactating, black-and-white Holstein cows were used in a free-stall system. Rectal temperature, respiratory frequency, ambient temperature and relative humidity were recorded at 3:00 a.m., 7:00 a.m., 11:00 a.m., 3:00 p.m., 7:00 p.m. and 11:00 p.m. The results demonstrate that despite the temporal variations that occurred throughout the evaluation days, the confined animals maintained their body temperature in balance.

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Thermal Perception in the Mediterranean Area: Comparing the Mediterranean Outdoor Comfort Index (MOCI) to Other Outdoor Thermal Comfort Indices

Energies ◽

10.3390/en9070550 ◽

2016 ◽

Vol 9 (7) ◽

pp. 550 ◽

Cited By ~ 30

Author(s):

Iacopo Golasi ◽

Ferdinando Salata ◽

Emanuele de Lieto Vollaro ◽

Massimo Coppi ◽

Andrea de Lieto Vollaro

Keyword(s):

Thermal Comfort ◽

Mediterranean Area ◽

Outdoor Thermal Comfort ◽

Thermal Perception ◽

Comfort Index ◽

Outdoor Comfort ◽

The Mediterranean ◽

Comfort Indices

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Measuring the effects of heated windows on thermal comfort

Pollack Periodica ◽

10.1556/606.2021.00361 ◽

2021 ◽

Author(s):

Balázs Cakó ◽

Dalma Lovig ◽

András Ózdi

Keyword(s):

Surface Temperature ◽

Thermal Comfort ◽

Window Glass ◽

Measuring Instruments ◽

Thermal Manikin ◽

Research Project ◽

Predicted Mean Vote ◽

Set Up ◽

Comfort Parameters ◽

Comfort Indices

AbstractDuring the following research project, the effects of an electrically heated window on the thermal comfort parameters of permanently occupied spaces were examined. A thermal manikin and a Testo 400 comfort-meter were used for the tests. To characterize the space, the predicted mean vote and predicted percentage of dis-satisfied method was applied. The examination of the comfort indices took place in the vicinity of an electrically heated window glass. During the measurements the surface temperature of the glazing was changed, alongside the distance from the glazing at which the measuring instruments were set up. The project aimed to assess the results measured by the thermal manikin and assess the usability of heated window glazing, taking thermal comfort into account.

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The role of clothing in thermal comfort: how people dress in a temperate and humid climate in Brazil

Ambiente Construído ◽

10.1590/s1678-86212017000100124 ◽

2017 ◽

Vol 17 (1) ◽

pp. 69-81 ◽

Cited By ~ 5

Author(s):

Renata De Vecchi ◽

Roberto Lamberts ◽

Christhina Maria Candido

Keyword(s):

Thermal Comfort ◽

Thermal Environment ◽

Thermal Conditions ◽

International Standards ◽

Humid Climate ◽

Great Opportunity ◽

Input Variables ◽

Air Speed ◽

And Gender ◽

Save Energy

Abstract Thermal insulation from clothing is one of the most important input variables used to predict the thermal comfort of a building's occupants. This paper investigates the clothing pattern in buildings with different configurations located in a temperate and humid climate in Brazil. Occupants of two kinds of buildings (three offices and two university classrooms) assessed their thermal environment through 'right-here-right-now' questionnaires, while at the same time indoor climatic measurements were carried out in situ (air temperature and radiant temperature, air speed and humidity). A total of 5,036 votes from 1,161 occupants were collected. Results suggest that the clothing values adopted by occupants inside buildings were influenced by: 1) climate and seasons of the year; 2) different configurations and indoor thermal conditions; and 3) occupants' age and gender. Significant intergenerational and gender differences were found, which might be explained by differences in metabolic rates and fashion. The results also indicate that there is a great opportunity to exceed the clothing interval of the thermal comfort zones proposed by international standards such as ASHRAE 55 (2013) - 0.5 to 1.0 clo - and thereby save energy from cooling and heating systems, without compromising the occupants' indoor thermal comfort.

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The Correlation Between Occupant Thermal Comfort and Discomfort Glare in Office Buildings in the Tropics: A Case Study in Thailand

Nakhara : Journal of Environmental Design and Planning ◽

10.54028/nj20201997118 ◽

2020 ◽

Vol 19 ◽

pp. 97-118

Author(s):

Kittiwoot Chaloeytoy ◽

Masayuki Ichinose

Keyword(s):

Thermal Comfort ◽

Field Survey ◽

Office Buildings ◽

Sensation Level ◽

Comfort Index ◽

Index Evaluation ◽

Discomfort Glare ◽

The Tropics ◽

Comfort Indices

This study aims to clarify the correlation between thermal comfort and discomfort glare. The field survey was performed in office buildings located in Thailand using the comfort indices and the questionnaire survey. The agreement can be found with respect to the glazing performance and sensation level, and the comfort index evaluation must be carefully concerned, as there is a discrepancy in occupants’ responses. It is necessary to comprehensively study the effects of thermal comfort and discomfort glare separately, along with their interactions. The post-occupancy survey is required to optimally enhance the occupants’ comfort assessment.

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Assessment of thermal comfort indices in an open air-conditioned stadium in hot and arid environment

Journal of Building Engineering ◽

10.1016/j.jobe.2021.102378 ◽

2021 ◽

Vol 40 ◽

pp. 102378

Author(s):

Saud Ghani ◽

Ahmed Osama Mahgoub ◽

Foteini Bakochristou ◽

Esmail A. ElBialy

Keyword(s):

Thermal Comfort ◽

Arid Environment ◽

Comfort Indices

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Building Retrofit and Energy Conservation/Efficiency Review: A Techno-Environ-Economic Assessment of Heat Pump System Retrofit in Housing Stock

Sustainability ◽

10.3390/su13020983 ◽

2021 ◽

Vol 13 (2) ◽

pp. 983

Author(s):

Mustapha Mukhtar ◽

Bismark Ameyaw ◽

Nasser Yimen ◽

Quixin Zhang ◽

Olusola Bamisile ◽

...

Keyword(s):

Energy Conservation ◽

Thermal Comfort ◽

Heat Pump ◽

Cooling System ◽

Commercial Buildings ◽

Optimization Techniques ◽

Hot Water ◽

Environmental Benefits ◽

Pump System ◽

Air Conditioners

The world has not been able to achieve minimum greenhouse gas emissions in buildings’ energy consumptions because the energy and emissions optimization techniques have not been fully utilized. Thermal comfort is one of the most important issues for both residential and commercial buildings. Out of the 40% of global energy consumed by buildings, a large fraction is used to maintain their thermal comfort. In this study, a comprehensive review of the recent advancements in building energy conservation and efficiency application is presented based on existing high-quality research papers. Additionally, the retrofit of the heating/cooling and hot water system for an entire community in Cyprus is presented. This study aims to analyze the technical and environmental benefits of replacing existing electric heaters for hot water with heat pump water heating systems and the use of heat pump air conditioners for thermal comfort in place of the existing ordinary air conditioners for space heating and cooling. One administrative building, 86 apartments (including residential and commercial) buildings, and a restaurant building is retrofitted, and the feasibility of the project is determined based on three economic indicators, namely; simple payback period (SPP), internal rate of return (IRR), and net present value (NPV). The electrical energy required by the hot water systems and the heating/cooling system is reduced by 263,564 kWh/yr and 144,825 kWh/yr, respectively. Additionally, the retrofit project will reduce Cyprus’ CO2 emission by 121,592.8 kg yearly. The SPP, IRR, and NPV for the project show that the retrofit is economically feasible.

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Performance Analysis of Hybrid Desiccant Cooling System with Enhanced Dehumidification Capability Using TRNSYS

Applied Sciences ◽

10.3390/app11073236 ◽

2021 ◽

Vol 11 (7) ◽

pp. 3236

Author(s):

Ji Hyeok Kim ◽

Joon Ahn

Keyword(s):

Thermal Comfort ◽

Cooling System ◽

Operation Mode ◽

Heat Removal ◽

Simulation Models ◽

Coefficient Of Performance ◽

Dimensional Structure ◽

Dominant Factor ◽

Exhaust Heat ◽

Chp System

In a field test of a hybrid desiccant cooling system (HDCS) linked to a gas engine cogeneration system (the latter system is hereafter referred to as the combined heat and power (CHP) system), in the cooling operation mode, the exhaust heat remained and the latent heat removal was insufficient. In this study, the performance of an HDCS was simulated at a humidity ratio of 10 g/kg in conditioned spaces and for an increasing dehumidification capacity of the desiccant rotor. Simulation models of the HDCS linked to the CHP system were based on a transient system simulation tool (TRNSYS). Furthermore, TRNBuild (the TRNSYS Building Model) was used to simulate the three-dimensional structure of cooling spaces and solar lighting conditions. According to the simulation results, when the desiccant capacity increased, the thermal comfort conditions in all three conditioned spaces were sufficiently good. The higher the ambient temperature, the higher the evaporative cooling performance was. The variation in the regeneration heat with the outdoor conditions was the most dominant factor that determined the coefficient of performance (COP). Therefore, the COP was higher under high temperature and dry conditions, resulting in less regeneration heat being required. According to the prediction results, when the dehumidification capacity is sufficiently increased for using more exhaust heat, the overall efficiency of the CHP can be increased while ensuring suitable thermal comfort conditions in the cooling space.

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ASHRAE Likelihood of Dissatisfaction: a new right-here and right-now thermal comfort index for assessing the Likelihood of Dissatisfaction according to the ASHRAE adaptive comfort model

Energy and Buildings ◽

10.1016/j.enbuild.2021.111286 ◽

2021 ◽

pp. 111286

Author(s):

Salvatore Carlucci ◽

Silvia Erba ◽

Lorenzo Pagliano ◽

Richard de Dear

Keyword(s):

Thermal Comfort ◽

New Right ◽

Comfort Index ◽

Adaptive Comfort

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Comfort-energy nexus in naturally ventilated affordable mass housing with alternative constructions in the developing world

10.5194/egusphere-egu21-8003 ◽

2021 ◽

Author(s):

Roshmi Sen ◽

Shankha Pratim Bhattacharya ◽

Subrata Chattopadhyay

Keyword(s):

Energy Efficiency ◽

Thermal Comfort ◽

Thermal Load ◽

Mixed Mode ◽

Developing World ◽

Assessment Model ◽

Strong Positive Correlation ◽

Mass Housing ◽

The Past ◽

Comfort Indices

There is a strong positive correlation between thermal comfort quality experienced inside a building and its energy efficiency. This is more obvious in case of mechanically ventilated spaces where the energy gains are directly related to the thermal load, as compared to free running or naturally ventilated spaces. Current state of arts assess the energy efficiency of building envelops in terms of the cumulative thermal load in the operating phase of the building that are catered by mechanical ventilations. Our study aims at addressing this gap of research in assessing the thermal comfort quality of naturally ventilated residential living spaces. Our study is designed in a warm-humid climate setting and in the context of affordable mass housing in the developing world where mechanical ventilation is unaffordable or affordable only for a definite period of the day and during peak summer seasons; such buildings are said to be operating in temporal mixed mode.Affordable mass housing constitutes 95% housing demand in the residential sector in India. Various alternative materials and composite roofing and walling envelops have been envisioned in the past decade for such constructions, however, their effectiveness in terms of comfort quality has not been assessed for naturally ventilated envelops. Our study introduces a model to assess the thermal performance of naturally ventilated bedrooms constructed with alternate building envelop configurations. We attempt to review&#160; and compare alternative walling technologies and the currently emerging mass housing construction systems in India with the base case housing envelop constructions commonly in practice in India that use ordinary burnt clay brick walls and reinforced concrete roofs. We compare the thermal comfort purveyed in the indoor bedroom spaces using the adaptive thermal comfort model in EN15251 as thermal neutrality temperature. We assess and compare alternative envelop performance using two measuring thermal comfort indices suited for naturally ventilated scenarios - the discomfort hours index and the cooling indoor degree hours index. Discomfort hours measures the number of hours of discomfort experienced during the summer solstice and spring equinox months whereas the cooling indoor degree hours measures the cumulative average temperature elevation from the comfort temperature in the hours marked as discomfort hours. In our study, light gauge steel framed structure with foam concrete filling records the minimum number of discomfort hours, however purveys maximum cooling indoor degree hours.The above two comfort indices have not been compared in the past to assess the thermal comfort quality in naturally ventilated or temporal mixed mode buildings. Our study frames a thermal comfort assessment model for naturally ventilated envelops and thereby offers a paradigm shift from life cycle cooling load minimization models which are appropriate for mechanically conditioned spaces. Our observations are also important for mass housing envelop selection and in the context of the current policy frameworks in the developing world, aimed at minimizing the projected demand for residential space cooling and future energy footprints in the housing sector.

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