environmental building design performance modelling and simulation

Environmental Building Design performance modelling and simulation

Computational Design in Architecture

Prepared by: Dr. Nagham Ali Hassan

PhD in environmental design, energy efficiency and renewable energy

Dr. Nagham Ali Hasan 2

Agenda:

The need for Environmental Building Software Tools

Aspects of using environmental design tools ED-Tools: selection and evaluation criteria How to select the best simulation software? What a future environment for building system

modeling and simulation may look like?


Introduction:

Spitler (2006) states that “simulation of building thermal performance using digital computers has been an active area of investigation since the 1960s, with much of the early work.

Over the last 20 years large and continuous increases in computational development of software tools that designed to help designers and environmental engineering consultants make such predictions.


1. Economic and social pressures on natural resources globally

2. Climate change is a growing concern politically

3. Mitigation of greenhouse gas emissions and adaptation to a changing climate are priority issues

Why Environmental Building Performance Simulation ???

material energy water land timber0%

10%

20%

30%

40%

50%

60%

70%

50% 45% 40%

60%70%Currently buildings:

Consume ~ 37% world energy Exploit ~ 40% of world resources Produce ~ 40% of world waste


Dynamic interactions of (continuously changing) sub-systems in a building context.


• Decisions making:

Energy use, indoor air quality and occupant thermal and visual comfort in buildings are largely influenced by decisions taken in the early stages of design, often by choices made even before design commences.


What Is Modeling??

Purpose of a model is:1. to enable the analyst to

predict the effect of changes to the system.

2. a model should be a close approximation to the real system and incorporate most of its salient features.

A model is a representation of the construction and working of some system of interest.

Fig: Designbuilder model interface

Modeling is one way of attaching metrics to abstract policy and regulatory rhetoric. These scenarios can augment team-based decision making and business strategy formulation

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Systems, Models, and Simulation

Dr. Nagham Ali Hasan

Ways to study a system

A good model is a judicious trade-off between realism and simplicity

Generally, a model intended for a simulation study

The model should be flexible and easy of use


Simulation is used to simulate everything from games to economic growth to engineering problems.

Simulation can be one tool used to examine possible scenarios that can be followed.

What is simulation?


Building Form Optimization for Natural Ventilation with Using CFD simulation, ISOENV with MODU Architecture NY, 2014

Automation simulation


Aspects of using environmental design tools

What tool, which one?

What for, why?

When?

How to (how not to) ?

What does result mean?

Building software tools can evaluate:1. Energy efficiency, 2. Renewable energy, 3. Sustainability in buildings

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When?Simulation tasks:

Current use of performance simulation in practical building design.

The actual application is

generally restricted to the final phases in building design

Dr. Nagham Ali HasanThe application stages:


Energy SimulationLoad CalculationRenewable EnergyRetrofit AnalysisSustainability/Green Buildings

Envelope SystemsHVAC Equipment and SystemsLighting Systems

Atmospheric Pollution (CO2)Energy EconomicsIndoor Air Quality (IAQ)Solar/Climate AnalysisVentilation/AirflowWater Conservation

Whole Building Analysis

Materials, Components, Equipment, & Systems

Other Applications

What tool, which one? Building simulation tools by category

Few of the available tools deal with all of the tasks

and operations encompassed by

environmental design.(Whole Building

Analysis)

Some were designed to deal specifically with only

one or some of these processes.

(Codes & Standards)


ED-Tools: selection and evaluation criteria

COGNITIVE CRITERIA (what does the tool do ?)

Heuristic Domain (capabilities / suitability )

Hermeneutic Framework (meaning and value) what kind of outputs are provided (form / detail)?

• how does the tool work?• which physical processes are modelled or

omitted ?• what simplifications are made?• what does the tool help find?• what does the tool does not find?

• what do the outputs mean, how do they compare with other available data and with targets and benchmarks?

• can we bypass the tool's modelling or other limitations and how?



Applicability range of use (simple - complex)

PRACTICAL CRITERIA (usability and user-friendliness)

Ease of Use (how fast to learn, how easy to use?)

how fast to get results? what communication with user? how easy to make changes, re-run

and draw comparisons?

range of application (single purpose - multiple)

range of action (single task - multitask)

accuracy practical usefulness / comparability



documentation and training available technical support from developer? further development? peer group / community of users

MARKET CRITERIA (acquire or not ?)

Cost

Support and Updates

purchase cost (hardware / software license )

speed and ease of learning (time / knowledge required)


The tools outputs can include:

databases, spreadsheets, component and systems

analyses, and whole-building energy

performance simulation programs

eQUEST software output

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Input data questions: In order to improve predictions and help designing

more robust solutions: should We focus on getting all the required “correct” data?? or should we rather be more realistic and take (sometimes

huge) physical and scenario uncertainties into account??

What is more relevant: Getting the answers right, or Getting the right answers ?


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simulation model steps The steps involved in developing a simulation model,

designing a simulation experiment, and performing simulation analysis are:


Identify & Formulate the problem

Collect and process real system data. &develop the model

Validate the model. Select appropriate

experimental design

Perform simulation runs.


The problem can be solved

using "common

sense analysis“

it's easier to change or

perform direct experiments on the real

there aren't proper

resources available for the project or there

is no data – not even

estimates

project expectations can't be met

Don’t simulate when …


What a future environment for building system modeling and simulation may look

like???


Conclusion The most widely used from among the tools that deal with thermal analysis

have become increasingly more designer-oriented aiming to address both three-dimensional visualisation (and thus also studies of solar access and shading design) and the processes of natural ventilation and solar gain that are of critical importance in contemporary building design.

With increasing computer power there has been a continuous trend of integration and greater capability.

Calculations that needed to be run overnight a few years ago are now performed in a few minutes.

Nevertheless, there is still discrepancy between designers' conception of realism and accuracy and that possible by the application of most of the current tools.

Clearly users must have an understanding of the underlying structure and theoretical basis of the tools they use

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Thank you


environmental building design performance modelling and simulation

Engineering