Building Simulation - Science topic

I am working on estimating peak power demand for buildings. This might involve Solar cells. If it involves solar cells then mostly it would be advisable for me to go with TRANSYS . But I am interested in the general scenario of estimating peak power demand. Generally which out of two EnergyPlus or TRANSYS softwares is good to go??

Dear All

Does any body help me who to add to create multi-nodes in one zone in Type 56 in TRNSYS?

Many thanks in advance

The technology of digital twins is used, among other things, to simulate production, logistics processes in business entities, i.e. in the microeconomic field. The creation of digital twins for specific economic and financial processes carried out in economic entities supports the management of these entities. Computer simulations of e.g. production processes, offering of services, supply and procurement logistics, distribution logistics, marketing communication with customers, etc. save time and money, as possible errors in decisions generate much smaller negative effects if they are realised not within the framework of real processes and a kind of experimentation on a functioning enterprise, company, corporation, institution, etc., but within the framework of computer simulation. but within the framework of a computer simulation in which various alternative variants of the development of the economic and financial situation of a company are considered and compared with each other as forecasts of specific processes defined for the following days, weeks, months, quarters or years. Therefore, since the pandemic, many companies and enterprises in Poland have been investing in the creation of IT systems equipped with digital twin technologies, within which it is possible to create multi-criteria, multi-faceted, complex simulation models of specific economic and other processes realised within the company, and/or simulation of processes realised at the level of the company's relations with the environment, with business partners, customers, cooperators, etc.

On the other hand, the possibilities of creating simulations for macroprocesses, i.e. e.g. macroeconomic processes, natural processes, technological processes, geological processes, social processes, long-term climate change, cosmological processes, etc., through the use of digital twin technologies and also other Industry 4.0 technologies, including learning machines, deep learning, artificial intelligence, analytics carried out on Big Data Analytics platforms, are a matter of debate. Year on year, due to technological advances in ICT, including the use of new generations of microprocessors characterised by ever-increasing computing power, the possibilities for increasingly efficient, multi-criteria processing of large collections of data and information are growing. Artificial intelligence can be particularly useful in the field of selective and precise search for specific, defined types of information and data extracted from many selected types of websites and real-time transfer and processing of these data in database systems organised in cloud computing on Big Data Analytics platforms, which would be accessed by a system managing a built and updated model of a specific macro-process using digital twin technologies.

In view of the above, I address the following question to the esteemed community of scientists and researchers:

What do you think about this topic?

What is your opinion on this subject?

Please respond,

I invite you all to discuss,

Thank you very much,

Warm regards,

Dariusz Prokopowicz

Dear All,

I want to model a horizontal automated slat (motorized Louvers) on TRNSYS to simulate the daylight and heat gain/radiation through the window with the slats.

I am wondering how can I incorporate the shading device i.e. the horizontal slats on my model. Is it possible to draw the slats on google sketchup TRNSYS 3d plugin and do the trnsys calculation of daylighting and thermal radiation?

Is it possible to model these slats and change the tilt angle of the horizontal slats?

Thank you in advance.

Best regards,

Ashmin Aryal

I used TRNSYS for most of my researches, especially for building simulations. I would like to learn more about EnergyPlus as well as its pros and cons. Please share your insights. Thanks in advance

I would like to know whether there is a direct relationship between quantum computer technology and artificial intelligence. Can you provide your explanation with examples for more understanding?

I'm going to analyze wind flow in an urban area and the results of the velocity field are important. Envi-met looks good in thermal analysis and temperature measurement but minimizes the level of detail of buildings (which I do not know how much it affects the results). UrbaWind is another option I'm familiar with. Do you have any idea about it?

What about Ansys? Envi-met has the ability to get geometry from Google Maps, but I think importing geometry to Ansys could be difficult.

Ansys 19.2 R2 and 2020 R1 versions of Additive Manufacturing Workbench is convenient for powder-based Additive Manufacturing processing. However, in this workbench, there is a machine parameter setting dialogue box and this parameter setting dialogue box has not included the laser power parameter. Without laser power, the powder material will not melt. So, how to add laser power in the machine parameter setting?

Good morning, everyone. To make simulations of a building what are the differences and common points between the following software: (Energy plus, Codyrun, Radiance).

Hello,

I'm about to start a project about designing an optimal heating algorithm for outdoor pools and hot tubs. The algorithm we are aiming for should take into consideration not only the current water and air temperature, relative humidity, pool surface and volume but also the predicted temperature in the next 24h in order to minimize the necessary heating needed to attain and keep a given water temperature (ex: 27 deg) in a certain time (like in 6h when people will bathe at 13h00).

I would be looking for the following two kind of advice:

What appears different with our project is the fact that the required heating will be influenced by much later acquired solar heat during the day. How best to take such long term effect into account?

I have a strong mathematical and programming background but no experience with either software or FEM/CFD. Any suggestion about which tool might be easier to model and experiment with for this problem?

Regards,

Bruno

Hi there,

I am looking for tips and tricks on how to model a cooling coil

I would like to perform building simulation under future climate. The time interval of the most detailed GCMs is every six hours. Is it possible to derive hourly weather data from GCMs using RCM (RegCM)? Thank you.

I need someone to help me write the Physics for Simulation using Cosmol Multi Physics:

Fresh air is introduced into the coil at the inlet which is the left hand side of the coil. The shell consists of hot flue gas passing through it to heat the coil and the Air passes out through the outlet at the right hand side.

I want to simulate the temperature at the outlet over a period of 5 hours.

The focus of the Simulation is shown in the attached file below based on the error report from the COSMOL Simulation result. I need help to write

the Physics for Cosmol addresss the error.

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.

As i know , if we can realize the DNA structure , we can simulate it in computer . then we can try to rebuild it if possible .

so Given the technological progress, is it possible in the future?

Regarding energy measurements in building sector I am using energy plus to simulate energy consumption in buildings. I am thinking how to evaluate and prove that my simulations are worthy?

I am making a LAMMPS simulation for a surface grinding procedure for my final year Mechanical Engineering project. Does anyone know where I could find the parameters (Epsilon and Sigma) for the Lennard Jones interaction?

Maybe eam too but I want to keep the model as basic as I could.

Dear all,

I have modeled a building in TRNSYS. I am cooling the building using the radiant panel on the roof integrated with simple cooling coil and other heat recovery devices (like enthalpy wheel, round around coil), for representing the radiant room.

I wanted to see the change in cooling load with a change in building aspect ratio the aspect ratio of the building from 1:1 to 4:1. The building with a 1:1 aspect ratio is 20m * 20 m * 3m and the building with a 4:1 aspect ratio is 40m *10m * 3m.  On doing so the cooling load of the building increased by around 4%. In my opinion, the cooling load of the building with an aspect ratio of 4:1 from 1:1 should increase more. Why is it just 4%?

Hello everyone, im currently running a simulatión of pyrolysis of waste tyres, and I have been trying to estimate the amount of electricity that the crusher requires to reduce the particle size.

However, the following error appears.

DUTY NOT CALCULATED BY UOS BLOCK ,

UTILITY RATE NOT CALCULATED FOR UTILITY E

I honestly dont know what to do. It would be great if anyone could help out.

Im attaching the simulation file, in case anyone wants to see it. I´d be thankful for any advice on how to improve the simulation as well.

Thanks in advance

In building E+ weather file, three types of Irradiance data are requested: GHI (Global Horizontal Irradiation), DHI (Diffuse Horizontal Irradiation) and DNI (Direct Normal Irradiation). With an usual weather station only GHI data are available, so is necessary to calculate the other components. Several model to calculate DHI starting from GHI were tried (UNI 8477, Iqbal, etc), but results are not satisfactory to calculate a reliable DNI data set.

I was trying to understand the resistance model of the "integrated Model for Chilled Ceiling Panels" in TRNSYS 17. For that, I am reading and studying the "TRNSYS 17 manual volume-5", "Multizone Building modeling with Type56 and TRNBuild". I want to build up a thorough understanding of this model. I do not find any reference for this model.

It would be great if anyone can refer me to literature for this model, a research paper, or something.

I am trying to simulate solar cell in AMPS .

But for simulation it needs material property like Relative Permittivity, Bandgap Eg (ev), Density of states in conduction band Nc (cm-3), Electron mobility μn (cm2/v/s), Hole mobility μp (cm2/v/s), Donor concentration Nd (cm-3), Acceptor concentration Na (cm-3), Affinity etc.

is there any easy way to get all the property of a individual material in a particular website or resource.

The Energy plus documentation (input/output) specifies that for typical commercial buildings in the USA, a reasonable default value for ground temperature: building surface is 2 degC less than the average indoor space temperature. And a practician in 2011 mentions that he has seen many simulations doing simplified method:

- using the last month's mean temperature, less 1 degree.

( http://energy-models.com/forum/ground-temperature-building-surface )

Similar to the Energy+ O/I documentation and Aside from applying:

- What is the best and easiest (more abstract) method, to input reasonable default values as a ground monthly temperature for small/large residential building models?

I am modelling a building in TRNSYS with radiant cooling panel equipped with DOAS(Dedicated Outdoor air system) .

I need to calculate the cooling load. I calculated the cooling load by using "mcdt", the sensible heat taken by the cooling water in the radiant panel. And the rest is taken by the DOAS(Cooling coil) which is mcdt for sensible load and mLdt for the cooling load.

I want to check the heat gain from the building envelope, the occupants, lighting and the equipment and compare it with the cooling load i calculated.

Can you please suggest me how to find the gain from the walls, occupants,equipments and lighting by using the "built in output Q" in TRNBuild.

Can you kindly suggest me what "Q" value should i use from the TRNBuild output file of Type 56?

Exploring the context of urban form and energy integration shall help as an efficient measures beyond the building scale in improving the energy performance of buildings in urban areas.. Many energy models and techniques have been developed for this purpose in recent years. However, these models usually adopt the perspective of the building designer: they tend to consider buildings as self-defined entities, neglecting the importance of phenomena that occur at the urban scale. Urban geometry affects urban microclimate.. As noted by Givoni‘‘The outdoor temperature, wind speed and solar radiation to which an individual building is exposed is not the regional ‘synoptic’ climate, but the local microclimate as modified by the ‘structure’ of the city, mainly of the neighbourhood where the building is located’’. These changes in the urban environment result in modified energy consumption. Also, air pollution and noise are dependent on urban form, thus affecting the potential for natural ventilation via a behavioural mechanism. Despite the evident relationship between urban geometry and energy consumption, this link is generally neglected, possibly because of the complexity of the environmental processes involved. Most software for building simulation tends to concentrate on building performance ie, at the level of architectural and systems design, while neglecting urban environment.

Hi, I have used Design Builder for basic building simulations but the limitation with Design Builder is that it cannot simulate a green wall, even though green roof can be modelled on it. I have heard Envi Met can be used for the purpose but haven't used it. Looking for some guidance.

to integrate with building simulation

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.

I am creating a building multizone with TRNBuild /TRNSYS (Version 16)

I am using 2RC Equivalent circuit battery model (time domain) to fit  26650 LFP cell data at 25,50,0 °C. When I simulate, the RMSE (Root mean square error in mV) value is high at low and high SOCs. What is the reason ?

Does anybody know of a source for internal and external values for hc that could be used for building modelling?

hc woun’t be a static figure as it is a time-variant function of ΔT, velocity of fluid concerned and surface properties of the solid material, so for instance EnergyPlus software calculates hc dynamically. However I wonder if a source exists that gives average static values for material surfaces of various description?

Thanks

M royapoor

AMY- is Actual Meterological year or year to year hourly climatic data. This can be effectively used in building simulation for building performance evaluation.

i gave my first cell height is 0.0020 accordingly with roughness measurements (0.0019) Ks< first cell height. Can i run this model in LES. ( Model height is 0.7 , width is 0.15m and Domain height is 1.8 m all are accordingly with wind tunnel test section). 

Its is possible to run a terrain profiles simulation in ANSYS Fluent, accordingly with roughness parameters limitation (Ks< first cell height) in LES?

I came across a few new Python packages related to EnergyPlus IDF file manipulation: 

Are there any other new examples out there?

How to install over 1.8m colorbond wall?

Dear Sir/Madam,

I would like to instal colorbond to cover our site. However, according to wind speed, it is not available to build over 1.8m height. we pland to have a 2.4m colorbond but to do that, we need some kind of support or material which won't have demage even if wind is strong.

1. is there any calculation or formula that i need to use to calculate colobond maximum height?

2. what other material i can use to make 2.4m height?

best reagrds,

I would like to optimize the inspection and maintenance process in buildings, taking into account the future effects of climate change in their degradation. I mean, I would like to decrease the costs of them procedures, apply the suitable techniques in the accurate time, and increase the lifespan of the elements of the building rehabilitated.

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 ?

Does anybody know the best validated method for dynamically calculating the CHTC for a concrete ceiling inside a building? I know that great variations are reported (below are two good sources), but just wondered if anybody has a source that gives the best results for a naturally-induced scenario.

1- Review of external convective heat transfer coefficient models in building energy simulation programs: Implementation and uncertainty

2- Variability and impact of internal surfaces convective heat transfer coefficients in the thermal evaluation of office buildings

I have been looking in the literature for Benchmaring methods and I found many methods for that purpose. 

Could anybody advise about a start point (good reference) and what is the best method that can be used?

we currently have found some old aqueduct under the site of 22 stories building. it cost very much to excavate and improve soil, because as GPR shows, aqueduct developed about 10 m in depth !! origin soil is very hard marl.

I want to study the free oscillations of a 7-storey structure. Apply a displacement to external nodes of the tree by running "initial x disp" but nothing happens. I would like to deform the structure and let her go back to the equilibrium position but nothing happens. Can you tell me where I'm wrong? Maybe I should not use the initial command?

I was trying to model a 3D building in the SeismoStruct platform. The actual RC building has staircase in a corner region. Now my question is how can I model that staircase or can account the effect of the staircase during my analysis. Since I will be modelling only the stair slab so, I hope the element class will be same as regular slab. Note that the slab in this case will be inclined. Thanks in advance for all those who are going to contribute by answering my question.

We are undertaking a literature review task on positive and negative impacts that have resulted from simulated and actual insulation of residential and commercial buildings in Hot climates and Hot & Humid climates.

Aspects we are trying to consider include: 

1. Thermal comfort

2. When insulated, do the buildings store more heat

3. Condensation risk

4. Built fabric issues (i.e. durability)

Any referenced journal articles, peer reviewed conference papers or reports would be appreciated. 

Thanks, mark

I am simulating a building whose cooling load is 40 tons. I am using double effect absorption chiller type 697. I need to know how can I modify the external files according to my requirement. I need to know heat energy required from hot water to get the 40 tons of cooling. Can anybody help me with that?

simulation of solid desiccant cooling system

During checking simulation result from EnergyPlus, i found that result value of Fan Coil Heating Rate is different from Heating Coil Heating Rate. The target building in the model is equipped with FCU and Gas boilers, which means that hot water circulates through each Heating coil in FCU. so i thought that heating rate of Fan Coil and Heating Coil must have same value. But they don't. i cannot understand why it happened. Please explain why it happens if anybody know the reason. T^T

Using any advanced interface of Energyplus( Designbuilder etc.)

I am simulating a building which has about 48 tons cooling load. When I try to connect cooling coil type 697 with absorption chiller type 677, I get the following error message.

"TRNSYS Message 118 : The subroutine SAT of the utility routine PSYCHROMETRICS, which calculates the thermodynamic properties of moist air, has been called with a temperature below absolute zero (-273 C) Please check the type routine which calls the psychrometrics routine for possible sources of errors.

Reported information : Error 118"

If i reduce the cooling capacity of the cooling coil, the error message vanishes but chilled water temperature approches to 500 C.

Can anybody help me with this?

The valid standard ISO 10211 do not consider this possibility, and ignores this thermal flux which may increase LTT by 15% (see following publication with DOI: 10.13140/2.1.4451.8726).

In my opinion, inclusion of this heat flow is physically and technically reasoned, because the floor heating is often an integral part of the structure (floor, ceiling, etc.). This approach would however lead to pressure on the more precise solution of thermal bridges in such structures.

Would it be useful?

I would like to deepen a set of qualitative indicators for assessing (and monitoring) building vulnerability to earthquake when the information commonly used in literature are not available. In my case study the qualitative assessment of the building stock is too difficult do to the information about the project of the structural system are not available, building maps are not updated and the main construction elements are not visible. The building stock is a set of government buildings that could be strategic for managing the impacts of the earthquake.

With my research unit, we consider the building as a system and organized the element at risk in three classes: human life, building operation, information and data stored in the building. We posit that building vulnerability depends on three main conditions (sub-systems): structural capacity; use typology (including users number and typology); morphology and distribution of the space (indoor and out door). For each of that we prepare an inspection formt containing a set of potential indicators of the sub-system vulnerability.

Before of advancing in defining the assessment method, I would like to have a check with the scientific community about our first approach.

Suggests concerning the assessment method are welcome as well.

Dear experts,

I am doing a building simulation using TRNSYS. I already validated the thermal property of my base model.

Now I am going to simulate the building using the weather data of urban climate simulation. I am wondering that how could I determine the air infiltration rate for my simulation. I know that the air infiltration rate is strongly influenced by the wind direction, wind speed, the size of window, etc... but wind direction and wind speed seem to be the domain factors.

My question here is how to relate the wind conditions with the air infiltration rate?

Thank you very much for your nice answers!

Best regards,

NGUYEN Huy Tung

Lighting consumes about 30% to 40% of the total electricity use in large buildings in University. Commonly in building simulations, static time schedules for typical weekdays, weekends and holidays are assumed to represent the dynamics of lighting energy use. Lighting energy use, which can be influenced by occupant behavior in buildings. What is the better solution (low cost and high efficiency) to energy saving of lighting consumption in university? If we don't consider the solution involve any kinds of sensors. Any contribution is greatly appreciated.  

I am trying to find the total cooling load of building in TRNSYS. I get the output for sensible load but latent load is always zero. What could be the cause of this error?

[EnergyPlus building simulation] It's a technical question. I'm looking for a way of reporting transferred heat through specified surfaces of a building. I understand it seems not available in the current version of EnergyPlus. So, I'm gonna utilize other useful output variables, but I find the "Opaque Surface Inside Face Conduction" not listed in .rdd. I'd appreciate if someone could help me. Many thanks!

I'm working on a simulation in TRNSYS 17 and whenever i try using type 62 to export the data to an excel file something goes wrong.

Building simulation models for a solar combined cooling heating and power system with control optimization based on exergetic analysis parameters. Was hoping to receive articles on similar work.  

Kindly tell me which function or code would be used to stop the working of a water heating system, built in TRANSYS, for 3-4 months. The system will remain in working condition for the remaining months.

this question is asked in order to do a research for evaluating the effect of significant factors in ventilation system of building.

Any article, journal, or any publication will assist tremendously.

Is anyone using a solar envelope in topical areas? Is there any software to assist in calculations? I used to build this manually, but was wondering if there is anything anyone can suggest.

I'm using gromacs and both all atom and coarse grained forcefields are necessary.

Regards.

Many studies show significant discrepancies between simulated and measured energy use in buildings.

I'm interested in developing effective interventions in building sector energy policies. Are certifications and energy labels well structured? Is it different to use dynamic simulation or simplified evaluations (under the point of view of the energy level or class obtained)? In some countries energy labels can be obtained by using both strategies, but simplified processes are commonly used. Will it be better to request dynamic simulation for each new construction or renovation?

In the design phases, several passive strategies are typically considered based on climate analysis, building type, etc. I'm looking for specific examples in which such passive strategies identified are incorporated into the design, where their effects are quantified and/or optimized using simulation tools or otherwise.