Research Characteristics of Thermal Comfort of Urban Block Landscape Based on Knowledge Graph Analysis

The landscape environment of urban blocks plays a significant role in improving the comfort of urban thermal environment and promoting green and high-quality development.The 342 papers related to the research on the impact of urban block landscape environment on thermal comfort in China,collected by CNKI(China National Knowledge Infrastructure)from 2002 to 2022,are used as the research object.Through bibliometric statistical analysis,LLR algorithm,and cluster analysis,the current research status of the impact of urban block landscape environment on thermal comfort in China is analyzed and processed,and its external characteristics are identified.Using the information visualization software CiteSpace,the research topics in the field of the impact of urban block landscape environment on thermal comfort are presented in the form of knowledge graphs.Through co-occurrence analysis of keywords and trend of word frequency changes,the development trends of research hotspots and cutting-edge fields of the impact of urban block landscape environment on thermal comfort are determined,hoping to provide reference for future research in this field.

Optimisation of Thermal Comfort of Building in a Hot and Dry Tropical Climate: A Comparative Approach between Compressed Earth/Concrete Block Envelopes

Compressed earth blocks (CEB) are an alternative to cement blocks in the construction of wall masonry. However, the optimal architectural construction methods for adequate thermal comfort for occupants in hot and arid environments are not mastered. This article evaluates the influence of architectural and constructive modes of buildings made of CEB walls and concrete block walls, to optimize and compare their thermal comfort in the hot and dry tropical climate of Ouagadougou, Burkina Faso. Two identical pilot buildings whose envelopes are made of CEB and concrete blocks were monitored for this study. The thermal models of the pilot buildings were implemented in the SketchUp software using an extension of EnergyPlus. The models were empirically validated after calibration against measured thermal data from the buildings. The models were used to do a parametric analysis for optimization of the thermal performances by simulating plaster coatings on the exterior of walls, airtight openings and natural ventilation depending on external weather conditions. The results show that the CEB building displays 7016 hours of discomfort, equivalent to 80.1% of the time, and the concrete building displays 6948 hours of discomfort, equivalent to 79.3% of the time. The optimization by modifications reduced the discomfort to 2918 and 3125 hours respectively;i.e. equivalent to only 33.3% for the CEB building and 35.7% for the concrete building. More study should evaluate thermal optimizations in buildings in real time of usage such as residential buildings commonly used by the local middle class. The use of CEB as a construction material and passive means of improving thermal comfort is a suitable ecological and economical option to replace cementitious material.

Impact of Street Built Environment on Human Thermal Comfort in Summer

With the continuous intensification of the global greenhouse effect,thermal comfort has become a highly concerned issue in the living environment.The study explores the influencing factors and improvement strategies of urban street thermal comfort.The urban heat island effect,environmental parameters,building layout,and green planting all have a significant impact on the thermal comfort of streets.Improvement strategies include optimizing cultivating pattern of plants,adjusting street layout,and improving paving materials of road.The multi-layer vegetation structure provides green shade,reduces local temperature,and humidifies the surrounding environment.It should adjust the street orientation and aspect ratio to provide sunlight and ventilation,and reduce ambient temperature.Paving materials with low reflectivity and light color and permeable underlying surface should be chosen to reduce heat absorption,increase shading and greenery,and improve thermal comfort.

Effects of urban street trees on human thermal comfort and physiological indices: a case study in Changchun city, China

Planting trees along urban streets is one of the most important strategies to improve the urban thermal environment.However,the net impacts of urban street trees on human thermal comfort and physiological parameters are still less clear.On three similar east-west orientated streets with different degrees of tree cover-low(13%),medium(35%),and high(75%),urban microclimatic parameters and human physiological indices for six male students were simultaneously measured on three cloudless days in summer 2018.The results show that the differences in tree cover were predominant in influencing urban thermal environment and comfort.The street with the highest tree cover had significantly lower physiological equivalent temperature(PET) and more comfortable than the other two streets.The frequency of strong heat stress(PET> 35℃) was 64%,11 %,and 0%,respectively,for streets with low,medium,and high tree cover.For the six male university students,human physiological indices varied greatly across the three streets with different tree cover.Systolic blood pressure,diastolic blood pressure,and pulse rate increased with decreasing tree cover.The results also suggest that urban thermal environment and comfort had considerable impact on human physiological parameters.Our study provides reasons for urban planners to plant trees along streets to improve the thermal environment and promote urban sustainability.

An analysis on spatial variation of urban human thermal comfort in Hangzhou, China

Urban human thermal comfort(UHTC) is affected for interacting of weather condition and underlying surface framework of urban area. Urban underlying surface temperature value and Normalized Difference Vegetation Index(NDVI) were calculated using image interpreting and supervised classification technique by ERDAS IMAGE software using 1991 and 1999 Landsat TM images data. Reference to the relational standard of assessing human thermal comfort and other meteorology data of Hangzhou City in summer, air temperature and relative humidity variation of different land types of underlying surface were inversed. By choosing discomfort index as an indictor, the spatial distribution characteristic and the spatial variation degree of UHTC were estimated and mapped on a middle scale, that is, in six districts of Hangzhou. The main characteristics of UHTC spatial variation from 1991 to 1999 were revealed using a GIS-based calculation model. The variation mechanism were analyzed and discussed from the viewpoint of city planning, construction and environmental protection.

Quantitative Analysis of the Outdoor Thermal Comfort in the Hot and Humid Summertime of Shenzhen, China

Outdoor thermal comfort has always been a major issue due to its irreplaceable role in maintaining good health and energy use. Thus,quantitative analysis of outdoor thermal comfort and discussions on influential factors seem very necessary to achieve the climate-conscious urban design. Therefore,an outdoor thermal comfort questionnaire survey and the simultaneous field measurement were conducted in six different places during the hot and humid summertime in Shenzhen. The results show that the overall weather conditions during the investigation can be expressed with high temperature and high humidity with strong solar radiation. The micro-meteorological parameters of six test sites vary greatly due to their different regional spatial layouts.Moderate range of air temperature( Ta) is between 28 to 30 ℃ while that of relative humidity( RH) mainly concentrates in 60%-70% with the thermal sensation votes. The main influential factors impacting outdoor thermal comfort are obtained and Tahas the greatest effect. The overall thermal comfortable ranges in Shenzhen are expressed by the range of 28. 14-32. 83 ℃ of PET and 24. 74-30. 45 ℃ of SET*. With the correlation analysis between the characteristic parameters of regional spatial layout and thermal climate and thermal comfort,it reveals that increasing the coverage ratio of water and green space( S) helps lower Taand increase RH. The global solar radiation( G) has a significant negative correlation with the height of buildings( H) and a positive correlation with sky view factor( SVF). Overall,reasonable configuration of the regional spatial layout contributes to providing a thermal comfortable environment.

Thermal comfort evaluation of people in subway station

We analyzed the characteristics of subway station environment and the change of thermal comfort for passengers when they are in and out of the station. The dynamic thermal comfort evaluation model RWI(relative warmth index) and HDR(heat deficit rate) were built on the distinguishing features of public area in subway station. Taking one representative subway station in Nanjing as the research object, the thermal comfort conditions in different seasons and different parts were studied by field tests, questionnaires and model-evaluating. The calculated RWI shows that although the thermal comfort in Nanjing metro is relatively acceptable, ideal thermal comfort has not been achieved. And it is found that associated with predicted mean vote(PMV), using RWI can evaluate the thermal comfort more precisely.

Research on the Winter Thermal Comfort of Library's Atrium Reading Space in Harbin Universities

As a transition space,atrium not only organizes traffic,makes the flow line flexible,but also modulates the indoor micro-climate. Because of its good sense of space and lighting performance,designers generally set reading space around the atrium. But nowadays,people are more concerned with the external form of the architecture,rather than the thermal comfort conditions of the atrium reading space. This article chooses the universities' library atrium space of Harbin in typical city in cold regions as the carrier of research,testes the thermal environment of atrium reading space, analyzes the user 's subjective feelings of the thermal environment and establishes climate adaptation model applied to library buildings. This paper aims to study on Winter thermal comfort of universities' library atrium reading space in cold area. Bases on thermal comfort adaptive model,it establishes a reasonable heating methods and design temperature index of indoor thermal environment. Optimum comfort is obtained while achieving building energy efficiency and providing viewers a comfortable reading space.

Design of Rural Residence Based on Thermal Comfort: A Case Study of Chengdu Area

With the improvement of living standards, peasants have attached increasing attention to quality of living environment, indoor thermal comfort of rural residence has become a functional need of new countryside residence. Chengdu is a foggy area with shorter sunshine hours, humid air, more foggy but fewer windy days, so local residence is likely to be muggy, which influences comfort of residents seriously. According to relevant researches, most rural residences in Chengdu use only natural ventilation, and the indoor thermal comfort is poor. In view of this, this paper tried to improve indoor thermal comfort and quality of living environment from the perspective of residence functional design.

Layout Optimization of Riverside Residential Area Based on Thermal Comfort: A Case Study of Nanhua Village, Shenzhen

Based on the previous researches on building layout with thermal comfort, this paper Stud Shenzhen Nanhua Village to explore the way of using building layout to change thermal environment of riverfront residential areas. The results showed that a more comfortable outdoor thermal environment could be obtained by applying proper building layouts favorable for the thermal comfort of the Nanhua Village. It proves again that efficient and feasible building layout, which is suitable for a river microclimate, is important in improving thermal comfort of a riverside residential area. The study also provides a good example for the future architectural designs of a riverside residential area for obtaining thermal comfort.

Thermal Comfort Measurement and Landscape Reconstruction Strategy of Street Space Based on Decomposition Grid Method:A Case Study of Yangmeizhu Street

As an important public space in the city,street space is the second residence of people.Taking Yangmeizhu Street as the research object,this study established a street microclimate model in Beijing through microclimate measurement and simulation,and then calculated thermal comfort index of the street and evaluated thermal comfort of the street space and distribution model.The evaluation method used grid method to decompose and study and made several 10m×10m grids for inner space of the street,so as to compare deeply difference of microclimate environment in the street and analyze quantitatively relevance between street space elements(street pavement,street greening,building shadow coverage)and thermal comfort(physiological equivalent temperature PET)in the data.Finally,adaptive strategy of microclimate on street level was put forward to improve the environmental quality of public space in the old city by means of landscape design,aiming at creating a resilient and humanized street space and improving adaptability of microclimate and thermal comfort for living.

Optimization Method for Indoor Thermal Comfort Based on Interactive Numerical Calculation

In order to implement the optimal design of the indoor thermal comfort based on the numerical modeling method, the numerical calculation platform is combined seamlessly with the data-processing platform, and an interactive numerical calculation platform which includes the functions of numerical simulation and optimization is established. The artificial neural network （ANN） and the greedy strategy are introduced into the hill-climbing pattern heuristic search process, and the optimizing search direction can be predicted by using small samples; when searching along the direction using the greedy strategy, the optimal values can be quickly approached. Therefore, excessive external calling of the numerical modeling process can be avoided, and the optimization time is decreased obviously. The experimental results indicate that the satisfied output parameters of air conditioning can be quickly given out based on the interactive numerical calculation platform and the improved search method, and the optimization for indoor thermal comfort can be completed.

Effect of horizontal radiant temperature asymmetry on thermal comfort and environmental parameters in a warm sitting area

Taiwan is a hot and humid place;in addition,the sunlight is strong and sufficient,the naturally ventilated classrooms have large-area windows for better lighting and ventilation in Taiwan.However,subjects sitting close to the large-area windows will encounter the problem of radiant temperature asymmetry,which may cause local thermal discomfort during summer.Hence,this paper is to investigate the influence of horizontal radiant temperature asymmetry on the thermal sensation of subjects and the correlative variation of environmental parameters in a warm sitting area.The evaluation results show that the predicted mean vote(PMV)index can be used to predict the overall thermal sensation of a group of sedentary subjects in a warm environment with horizontal radiant temperature asymmetry;even subjects feel local discomfort on exposed parts of their body.The measured results of environmental parameters indicate that the averaged radiant temperature difference is about 4.6 ℃ from right shoulder to left shoulder;the temperature difference does not only cause correlative variations of other environmental parameters,but also result in thermal discomfort on the right cheeks and forearms of subjects in the warm sitting area.

Numerical Study on the Suitability of Passive Solar Heating Technology Based on Differentiated Thermal Comfort Demand

Indoor thermal comfort and passive solar heating technologies have been extensively studied.However,few studies have explored the suitability of passive solar heating technologies based on differentiated thermal comfort demands.This work took the rural dwellings in Northwest China as the research object.First,the current indoor and outdoor thermal environment in winter and the mechanism of residents’differentiated demand for indoor thermal comfort were obtained through tests,questionnaires,and statistical analysis.Second,a comprehensive passive optimized design of existing buildings was conducted,and the validity of the optimized combination scheme was explored using DesignBuilder software.Finally,the suitability of passive solar heating technology for each region in Northwest China was analyzed based on residents’differentiated demand for indoor thermal comfort.The regions were then classified according to the suitability of the technology for these.The results showed that the indoor heating energy consumption was high and the indoor thermal environment was not ideal,yet the solar energy resources were abundant.Indoor comfort temperature indexes that match the functional rooms and usage periods were proposed.For the buildings with the optimized combination scheme,the average indoor temperature was increased significantly and the temperature fluctuation was decreased dramatically.Most regions in Northwest China were suitable for the development of passive solar heating technology.Based on the obtained suitability of the technology for the regions of Northwest China,these were classified into most suitable,more suitable,less suitable,and unsuitable regions.

Evaluation of Thermal Comfort and Energy Usage for an Enclosed Cavity Indifferent Climatic Zones of India

The utilization of energy in building sectors comprises 30–40%of the entire global energy consumption.Most of the energy is being utilized for cooling&heating the buildings.These cooling and heating depend on the nature of climate for different places.In this,the detailed analysis of the building envelope across five areas(viz.Srinagar,Jaisalmer,New Delhi,Thiruvananthapuram and Bangalore)representing different climatic zones had been carried out.Simulations are performed for these locations using eQUEST and ANSYS software.Three of the result output from the eQUEST simulation are used to assess the different cases.These outputs are:total electrical energy consumption of the year,peak cooling load&peak heating load for a particular time of the year.Temperature variations and airflow for a fan with moisture influence are also simulated for five different locations by using the radiation model and shear stress transport in ANSYS.The internal temperature distribution in accordance with an occupant is also compared and discussed for the five regions.Lastly,the predicted mean vote and predicted percentage of dissatisfaction are found to be in the range of−0.50 to−0.99 for all zones that signifies 13%to 30%of people are dissatisfied with the indoor environment.

Energy Efficient Thermal Comfort Control for Residential Building Based on Nonlinear EMPC

For purpose of achieving the desired thermal comfort level and reducing the economic cost of maintaining the thermal comfort of green residential building,an energy efficient thermal comfort control strategy based on economic model predictive control(EMPC)for green residential buildings which adopts household heat metering is presented.Firstly,the nonlinear thermal comfort model of heating room is analyzed and obtained.A practical nonlinear thermal comfort prediction model is obtained by using an approximation method.Then,the economic cost function and optimization problem of energy-saving under the necessary thermal comfort requirements are constructed to realize the optimal economic performance of the dynamic process.The energy efficient thermal comfort MPC(EETCMPC)is designed.Finally,the comparison and analysis between EETCMPC and Double-layer Model Predictive Control(DMPC)is simulated.The simulation results reveal that when the clothing insulation is typical,the energy efficiency of EETCMPC is 8.9%and 11.6%,respectively,in the two simulation scenarios.When the clothing insulation varies with temperature,the energy efficiency of EETCMPC is 7.29%and 9.15%,respectively,and the total energy consumption is reduced by about 1.65%and 14.6%,respectively,compared with the typical clothing insulation.The economic performance is improved in the thermal comfort dynamic process of heating room.

Improving the Thermal Comfort of a Building by Adding a Layer of Straw over the High Floor

This document deals with the thermal characterization of a building with a layer of straw above the high floor. In the current environmental context, in Senegal, buildings are the biggest consumers of energy. This is due to the construction materials used. Almost of buildings in Senegal used concrete (cement + aggregates) as based material construction. Due to this, the buildings require air conditioning or artificial ventilation to ensure minimum comfort. In face of this situation, it becomes useful to propose methods for reducing this high energy consumption. In this work, we propose to add a layer of straw above the high floor of a building in Matam city (North Senegal). In this case, we designed and modeled one building of single room in which the walls are in briks and a concrete slab. A bale of straw is layered on this slab in order to determine its influence on the energy consumption of the building. This study shows that the straw has a strong influence on the energy consumption of a building and the slab + straw building is more energy efficient than the bare slab building.

Research on Thermal Comfort of Outdoor Space in Summer Urban Park: Take Mianyang Urban Park as an Example

One of the factors for the evaluation of the space environment is the comfort of outdoor activities spaces in urban parks. The space composed of different landscape elements has different microclimate environment. In this paper, in order to evaluate the role of thermal comfort in influencing resident’s assessment of the outdoor space and activities of the park, a thermal comfort survey was conducted on the outdoor open space of Mianyang Urban Park in summer. In this article, meteorological surveys, questionnaire surveys and observation of park attendance are selected to collect data. The physiological equivalent temperature (PET) assessment was selected as the index to evaluate resident’s thermal comfort level, and the comprehensive evaluation and analysis of the spatial thermal environment of different outdoor landscape elements in the park. The overall comfort of current visitors is mainly influenced by their subjective heat perception voting (TSV). In this article, we focus on providing microclimate adjustment considerations for urban park landscape design, and may help people understand the outdoor thermal comfort of Mianyang in summer, increase the using time of outdoor activities, and promote the use of outdoor space.

Research on the Difference of Human Thermal Comfort Perception in Outdoor Space of Campus in North China

Outdoor space on campus is an important place for daily activities of teachers and students,and there is an important connection between thermal comfort and users’ feelings.It is of great significance to explore the difference of thermal comfort perceived by human body for the effective use and renovation of space.With the typical outdoor space in the campus of North China University of Technology as the monitoring object,the influencing factors of the difference of human thermal comfort perception were analyzed by measuring the microclimate data of outdoor space in winter and the data of thermal comfort questionnaire.The results showed that the subjective feeling of human body to environmental thermal comfort in winter in outdoor space of campus in north China was correlated with various factors,and had significant correlation with gender and height.The research results are helpful to further explore the difference of thermal comfort perception.

Investigation of the Effects of Glazed Balconies uponThermal Comfort in Hot Tropical Region

The balcony is responsible to a series of effects on the environmental behavior of a building,mainly in relation of thermal comfort and air distribution to their indoor spaces.Currently a very common practice in several metropolitan areas is the closing with retractable glass panels in balcony openings.This work analyzed the effects of glazed balconies upon thermal comfort in a hot tropical region.Environmental parameters were carried out in a flat alternating the conditions of retractable glass panels to balconies.Thermal simulations were performed considering closing or not the glass door that divides the balcony room;the building material used on the balcony sill;and the use of curtains or shading devices.The results show the maximum mean hourly temperatures recorded on the balcony during the period when the retractable glass panels were closed,reaching peaks between 31.7 and 39.2°C,above the comfort range recommended by ASHRAE 55.All situations simulated show the thermal discomfort prevails in the use of the closed glass panels reaching DhTD of 94.55°C/day.Thus,this practice of using most of the closed retractable glass panels in the balconies presents disadvantages and inefficiencies especially in hot and humid tropical climate regions.