Questions related to Thermal Comfort
I'm working on adaptive thermal comfort (CIBSE TM52 / TM59). Calculating the running mean temperature using the formula Trm= 0.2Te(d-1) + 0.16Te(d-2) + 0.128Te(d-3) ... is giving me values for Trm significantly lower than the previous daily averages (Te(d-1), Te(d-2) etc).
From the formula this makes sense as we're adding 0.2 + 0.16 + 0.128 etc which is significantly less than 1.
But intuitively, this doesn't make sense. Shouldn't the running mean temperature be much closer to the previous few days' mean temperatures?
I study on some kind of infrared barrier and I don't know how to calculate normalized reflectance spectra weighted by human body radiation?
For example you can see results of this article but authors did not mention the calculation method:
I'm researching on the comparative analysis of the different waste-based innovations in the Philippines but the existing materials do not have information on its thermal properties. Is there any testing center in the Philippines that specializes in testing for thermal properties or maybe thermal comfort?
how to design a questionnaire for thermal comfort for a residential population residing in various streets to compare ?
I need at least two software which can simulate the shading properties of semi-outdoor spaces and thermal comfort conditions of those spaces. Beside Envi-Met, which one is capable to express these inputs with PET?
It must be:
first / for free.
Second / it calculates both thermal comfort and indoor air quality.
I'm planning on doing research about the relationship between city components (like buildings, streets, open areas, vegetation and etc.) and the thermal comfort of a city.
I would like to know there are any special methods, software for this.
Does anyone know if there is any rainfall threshold (mm/year, month or day, etc.) for a city to be considered "rainy" or "very rainy"? Or the rainfall intensity thresholds (weak, moderate, heavy, etc.)? Are there any international standards, for example from ISO or another institution? If there is a reference to support it, it will help better.
Ditto for wind speed thresholds (m/s or kt) for a place to be considered "windy". Does anyone know any references?
Thank you in advance for your attention.
Hello all! I want to simulate a DSF on a hot arid climate which is consists of interior shades in its cavity, so I need to calculate its effects on thermal comfort. I would greatly appreciate it if you kindly give me some solution or know any honeybee component which helps me on this occasion.
I am looking for a public available 3D building model dataset, BIM with sensor data for temperature, humidity, occupancy, and others IAQ parameters. This will be helpful with thermal comfort-related research. A proper citation will be given to original source.
I am currently working on my MSc dissertation with a focus on 'Impacts of urban surfaces i.e. roof surface, pavement surface and vegetation on urban micro-climate in hot arid regions'.
Envi-met simulation software was used to predict the air temperature of the micro-climate. However, due to the software's limitations the surface air temperature of the roof can not be calculated.
In outdoor space, can the Tmrt (mean radiante temperature) be lower than Ta (air temperature), and if it's the case, when or why can this happend?
Outdoor thermal comfort autonomy (OTCA) is one of the recently introduced induced for climate-conscious urban design. I was wondering if this new outdoor comfort metric has been embedded in the new versions of Ladybug Tools? Otherwise, I would really appreciate receiving your suggestion regarding the post-processing of data for the computation of OTCA.
I am working on a study that needs to assess thermal comfort at the interior spaces of buildings as well as their surrounding urban space. As far as I know, Envi-met is the most suitable software for this goal, while most simulation tools analyze thermal comfort particularly on indoor or outdoor spaces. I was wondering if there's any tool that simultaneously analyzes thermal comfort in both types of space.
Dear academic community,
I am a young researcher from architectural background. I am looking for possible novel approaches to evaluate outdoor thermal comfort in urban streets using artificial neural networks...suggestions regarding novel techniques, academic papers featuring research gap/future avenues and any link regarding this would be a great help!
Thank you !
Dear All, I have a scientific question which I hope you help me through: There is a class room (Volume = 210m3), which had Co2 value of 420 ppm and temperature 17°C when nobody existed in it and all windows were closed, after 30 minutes there was some students in the room, where co2 value reached 1200 ppm and temperature increased 1°C while windows are still closed, There is an equation in the german code which applies the variables: volume flow rate, co2 and number of people. I have tried to apply this equation but it doesn't work if volume flow rate or number of occupants = 0. What I know is that a student generates heat = 70 W. how do you think such a problem could be solved ? Best regards
I would like to know if it's possible to combine the factor loadings in two different components?
The research is related to thermal comfort and the variables in both components are related to thermal stress in outdoors.
The variables have been standardised and four components received with oblique rotation. The components I want to amalgamate is to temperature and the other is related to wind climate.
Would want to create a single scale combining these factor loadings in both components.
Your input is much appreciated.
I have temperature and percipitation data for some years and I would like to examine the thermal comfort of the region. In my knoledge even the calculation of the simpliest indices requires Relative Humidity or dew point..
Is there any bioclimatic index that I can estimate with my data?
Αlternatively, can I estimate relative hummidity or dew point from percipitation data?
Which are the most applicable models to analyze the energy effect and thermal comfort?
Models applies especially to occupant-controlled, natural conditioned spaces, where the outdoor climate can actually affect the indoor conditions and so the comfort zone
Many thanks in advance
I am looking for a formula to calculate specific temperature drop in duct based on airflow, knowing the specific power loss, airflow, thermal properties of the duct, and air temperatures. The goal is to be able to produce the graph attached.
Indoor environmental quality depends on thermal comfort, Indoor air quality, visual comfort and acoustics. There is a hierarchy of importance among these factors. Thermal comfort and air quality affects IEQ most. I want to know how much visual quality and acoustics contribute to IEQ
How can we restore the initial conditions of thermal comfort in a historic building (built heritage)?
We know that materials change their physical behavior because of their mishandling over time.
Based on your experiences, how we can increase in the developing countries - like Palestine - the awareness of architects & designers toward the energy used in their design and people in their living spaces? The big problem here is they believe that using the energy efficient solutions and stratigies in their design will increase its cost.
How can I use R statistical tool to find PMV / PPD thermal comfort model? Is there any other statistical tool for the thermal comfort model?
Can I couple IES-VE with other tools like MATLab or Modelica?
My research is focused on control for better thermal comfort and indoor air quality. So I want to use MATlab or Modelica, it will be helpful if it can be coupled with IES-VE by any mean.
I am looking for some technical content focused on studying the impact of conducting post occupancy evaluations and how POEs have helped in improving thermal comfort and energy efficiency post occupancy? It will be great if anyone can provide some leads.
Thanks in advance,
Energy consumption has been one of the most burning topic, and building(residential and commercial) consumes energy in excessive amount. Switching to Rat Trap Bond improves the thermal comfort, minimizes energy loss, emits less carbon-dioxide and is more economical. Similarly, introducing pitched roof can also contribute to thermal comfort and energy saving.
What building components when taken into account can contribute to energy saving?
Have experimental value of air velocity, air temperatue...etc. Is there any software to predict PMV and PPD in Thermal comfort by had parameters include air temperature, radiant temperature, air velocity and RH?
Is it better way to create program in visual basic (VB)
Does anyone have electronic version of 2017 ASHRAE Handbook and AHSRAE standard 55? It would be a great help if someone can share these two useful tools. My email address is firstname.lastname@example.org. Thanks a lot!
Please complete this questionnaire
Office type: Open space office/closed office
HVAC system: Yes/No
Natural ventilated NV: Yes/No
Thermal comfort scale
+1 Slightly cool
0 Comfotable, Neutral
+1 Slightly warm
Thank you a lot.
I'd like to calculate an outdoor indicator of comfort from a weather station network. My input values avalaible are :
- infrared solar flux
- direct normal irradiance
- wind speed
- air temperature
universal thermal climate index(UTCI)and physiological equivalent tempetaure(PET), which is commonly used in the evaluation of the thermal comfort of the human body?
My thesis is about the renewal of the old city. There are many ways to evaluate the thermal comfort of the human body. I picked two, and I don't know which is the most suitable. The individual will have a better understanding of the PET, but it's like UTCI is the most perfect.
I hope the expert can give the answer. THANKS
I am doing a research about interactive spaces in universities buildings, and I wish to measure this interaction by analyzing several variables that shape the interactive space including: visual connection, thermal comfort, daylight, furniture, circulation.
I wish to do this study by measuring these variable using Grasshopper in Rhino.
The point is that I can measure the environmental variables by ladybug but if I want to measure the non- physical variables, do you recommend any plugin?
Generally in the third world countries,whenever infrastructure are planned to be constructed or renovated the concept of thermal comfort has been neglected. Even research and project carried out regarding this topic is less emphasized. Thermal comfort has not been included in many curriculum as well.Is it really important to consider this factor while designing or constructing any structure and how important is it?
Which role takes the skin temperature and skin moisture level between skin and clothing layer in, in terms of performance level output?
I measured and evaluated skin temperature and skin moisture level during cycling with different cycling clothing setups on different participants. Since sweating is an individual property of each athlete, I'm trying to find a calculation or statements on which microclimate (between clothing and skin) is best fitted for the energy output of an individual athlete under specific environmental conditions.
I am conducting my PhD research and I would like to do some onsite field measurements which include temperature, relative humdity and global radiation. I plan to do these measurements for long time period ( 15 day) ... Any suggestions for a good affordable ones ?!
What are the keys of thermal comfort in your office?
Describe your office how it is,
If you need to use an HVAC system,
What about your adaptation?
Since Gagge proposed the concept of Standard Effective Temperature (SET), it has been modified many times. Even the defination of the standard environment of SET is disunified. What is the recognized definition of a standard equivalent environment? How to consider the metabolic rate and the related standard clothing in the standatd environment ?Is the version in ASHRAE Standard 55 realiable? What's the better version in practice to reflect the synthetic effects of several input parameters?
I have found some thermal comfort assessments included the survey of respondents' micro-climate control. May I know what is the importance of these questions and how does it link with the result of their thermal responses and comfort perceptions?
Looking forward for your sharing.
For air-conditioned buildings, the Predicted Mean Vote (PMV) model calculates a comfort score ranging from -3 (cold) to 0 (neutral) to 3 (hot).
For naturally ventilated buildings, the adaptive thermal comfort model (ATC) model calculates an indoor design temperature, around which a range is defined as comfortable for 80% (or 90%) of people.
Is there a way to compare these two different comfort metrics?
For example, if I simulate a space to be air-conditioned and determine a PMV of 1.5 at a given time, then I simulate the same space to be naturally ventilated and determine the indoor temperature to be 4K over the design temperature - in which scenario is the occupant more comfortable?
Asked another way: when using the ATC model, can I use the difference between the indoor temperature and the design temperature to determine a comfort score based on the same 7 point scale as the PMV model, in order to enable a direct comparison?
What are the assumptions that should be used for IES-VE software when I want to simulate a 2 storey house in the tropical climate to calculate air temperature and relative humidity inside the house?
What are the keys of thermal comfort in your office?
Describe your office how it is,
If you need to use an HVAC system,
What about your adaptation?
Your age, Sexe, positoin,
Considering the importance of the variable relative humidity, it is expected that adaptive models emerge that contemplate it in some way as an explanatory variable.
I have a few factors like temperature, humidity, radiation and thermal characteristics that affect thermal comfort inside a building. Now, I need the thermal simulation for a model in Ansys.
Is there a good calibrated sensor that you would recommend to measure the Mean radiant temperature? Something that will let me connect to a computer and record the data over time. It would be better if I could connect the sensor to an Arduino/Raspberry pi and get the sensor measurements.
I did find some systems that can record the data to a SD card so I can import it into my computer later but I could not find something that enabled me to get the readings in real time to analyze them.
It would be better if it is not very expensive (<$100).
I have several factors like temperature, humidity, radiation and natural ventilation (wind speed) that affect thermal comfort in my CFD model. Now, I need the thermal comfort results (PMV) for my office model in Ansys Fluent. I don't know how to use the abovementioned factors to get it.
As I understand, adaptive thermal comfort is calculated as a function of prevailing outdoor temperature. Inputting this value returns a fairly large comfort range, based on the fact that occupants can take adaptive measures (clothing change, opening windows, etc.).
I am currently testing natural ventilation simulations, to explore how building design can affect comfort. Air speed in a building is an important factor - two naturally ventilated buildings in the same location but different air speeds will be perceived differently.
Is there a way to make this explicit? I.e., is there a formula that adds wind speed as a parameter to the adaptive thermal comfort model, or is there a different model for this altogether?
PMV index depend on 6 factors: velocity, humidity, air temperature, mean radiant temperature, clothing insulation and metabolic rate. The first four can be found easily by, for example, using CFD. My doubt is how to fix the last two if I want to represent the iso-PMV lines.
Do I simply suppose a constant metabolic rate and clothing in the whole domain?
If I wanted to find thermal comfort of someone in a room, I would just do the average of PMV single point values in the space occupied by that person?
M: metabolic rate. INPUT
W: mechanical power. INPUT
H: heat exchange by convection. H=f(fcl, hc, Tcl, Ta)
R: heat exchange by radiation. R=f(fcl, Tcl, Tr)
Ec: heat exchange by sweating of the skin. Ec=f(M, W, HR)
Cres: dry respiration heat loss. Cres=f(M, Ta)
Eres: latent respiration heat loss. Eres=f(M, HR)
In which everything is INPUT except fcl, hc and Tcl. First two can be found directly using empirical equations and Tcl through an iterative process. This iterative is based on assuming Qcond_skin-clo=Qconv_clo-air+ Qrad.
I have the following two questions:
- Does it make sense to plot iso-PMV lines? By looking the algorithm it seems to me a whole body sensation instead of a single point property.
- How to find PMV value using numerical methods like CFD? Running a CFD code we get velocity, temperatures and humidity for single control volumes. So the only way to insert them in PMV algorithm is by doing an average of this properties surrounding the body, right?
I would appreciate any help or document in which these topics are explained in more detail.
Thanks in advance.
I'm looking for further information on occupant-centric retrofitting scenarios of non-domestic existing buildings.
Give me some basic idea of this software tool. also can we analyze humidity ratio, air-temperature and win-flow through this?
Which method is suitable for validation of physical measurement (environmental factor i.e, temperature, humidity, wind-speed) data for thermal comfort study in indoor environment.
The purpose of this question is to examine the thermal resistance of clothing and its relation with the thermal comfort of the body.
The aim of this research is to investigate the indoor air quality (IAQ) by characterizing the concentrations of different indoor air pollutants (VOCs) and their sources within a refurbished educational building and their effect on the health of occupants.
For the study, i am conducting an IAQ monitoring campaign by measuring indoor environmental variables (temperature, humidity, airflow), carbon dioxide levels and volatile organic compounds (VOCs) by diffusive (passive) sampling method for an 8-hour exposure spread out within different scenarios to assess impact of the building materials, furniture, occupant activities on IAQ.
For this purpose, i have found the Health Safety Executive, 2005 which gives permissible limits of different chemical substances but in the context of a workplace. The standards for schools such as Building Bulletin (BB) 101 (2006), Priority schools building program (PSBP, 2014), Guidelines on ventilation, thermal comfort and indoor air quality building bulletin 101 (2016) - Draft consist of values based on Total Volatile Organic Compounds (TVOC) i.e. TVOC > 300mg/m3 as an indicator of poor IAQ. However, specific values for individuals VOCs do not exist which can lead to undervaluation of the toxicity of different chemical compounds present in the space during assessment of health effects for the most susceptible group i.e. children.
So if anyone could lead to me to an appropriate standard or guideline for permissible limits and health effects of different chemical compounds for schools in UK.
Public space is a gathering place for various activities and each user can change at any time. Meanwhile, the comfort of space and place is one of the important things, not only about visual comfort but also thermal comfort.
How do you meet thermal comfort in a public space? whereas, thermal comfort is very subjective. Can we ignore that subjectivity?
CFD simulations clearly demonstrate that forgotten ancient Turkish architectural element “Cumba” can enhance ventilation rate by 276% and harvesting wind from different directions even in the single facade ventilation. Furthermore, the room’s mean air velocity and ventilation rate could be adjusted to a broad range of values with the existence of Cumba. As a passive strategy, understanding the working principles of “Cumba” can contribute the effectiveness of wind-driven ventilation strategies in modern dwellings.
During my visits to different countries I recognised the existence of architectural elements that have some similar characteristics with Cumba. I would like to ask any colleague to inform me about the names of these architectural elements (especially in some European countries). I know the "bay windows", they are common particularly in terraced houses (e.g. in UK), but they have some fundamental differences with Cumba. The details about Cumba can be found in the article; Aydin, Yusuf Cihat, and Parham A. Mirzaei. "Wind-driven ventilation improvement with plan typology alteration: A CFD case study of traditional Turkish architecture." Building Simulation. Vol. 10. No. 2. Tsinghua University Press, 2017.
the research goal is to achieve maximum thermal comfort in outdoor spaces in hot dry climate areas
Hello, I have a question about the last version of Airpak. Airpak is a precise
and fast responding software that is exclusively used for ventilation
cases and has a vast ability to present the temperature contours, velo-
city vector and stream lines and evaluating the indoor thermal comfort.
My question is:
What is improved in Airpak 3 compard to Airpak 2?
We are trying to estimate the power required by HVAC to obtain a desired temperature which we also forecasted based on historical data of occupant behavior and environmental parameters. Is there any theoretical equation that we can use to estimate the HVAC energy to obtain a desired temperature using the historical data of the outdoor temperature and the indoor temperature of the zone .
The CBE (http://comfort.cbe.berkeley.edu/) website is difficult to use for big sample data. I want to calculate ASHRAE 55, EN-15251 and adaptive thermal comfort of 1000 samples. Is there any source to download a spreadsheet to make calculations faster?
I need this equipment for evaluating thermal comfort in case study buildings. I would need to measure air temperature, relative humidity, globe bulb temperature, and air velocity. I couldn't find a good tool which measures particularly indoor air velocity and streams data online.
When we talk about human comfort, we usually think of thermal comfort, and many good models for individual thermal comfort have been proposed.
So my confusion is “How to measure the individual olfactory comfort?”. Could you tell me some models or theory related to it?
Or what factors can affect individual olfactory comfort?
Does water cooled condenser give low cooling energy/electricity than air and evaporatively condenser HVAC system for hot humid climate.. need explanation?
I want to calibrate my building energy model using measured temperature data, I know it can be done using measured heating/cooling energy consumption of building as mentioned in ASHRAE guidelines, but can we do it with temperatures also ?