blog section, Projects

National Grand Prize for Engineering - Syntec

L'hypercube is proud to have contributed to the Grand Prix National de l'Ingénierie 2021, won by AREP teams, for the transformation project of the Saint-Michel Notre-Dame station (RER C).

For the hypercube, it is the recognition of the Air Quality expertise, born during this project in 2017.
After preliminary study phases that were marked by the development of predictive models of air quality in train stations and a fruitful collaboration with the CSTB allowed us to develop a simulation framework to estimate the ventilation induced by train passages ("piston" effect),the main driving force of the air quality improvement on this project.

Subsequently, we had to deal with other site constraints, such as acoustics and flood control. It is precisely this collective and iterative work of the different engineering departments that was rewarded by the GPNI!

Below is a video presentation of the main challenges of the project:

Projects

Melun train station

An annual wind comfort study, in and around a new passenger building, as well as on the platforms.

  • "CSTB" wind comfort criteria,
  • 12 CFD simulations,
  • Local phenomena characterisation,
  • Mapping the wind comfort criteria : the probability of exceedance of a given threshold over a complete year, indoor as well as indoor.

#Paraview

Projects

Urban Heat Island modeling

In the beginning of 2021, we completed the development of a tool for simulating surface temperatures in an urban environment, using a weak coupling approach between temperatures and air velocities

The approach allows for comfort indexes computations at each point in space. It integrates the coupling of fluid mechanics simulations, together with sunlight and thermal dynamic regimes for the built environment.

Results of a case study around the Strasbourg train station (France) are presented next.

The following animation shows the evolution of comfort levels over the first week of the year Sit back and relax!

Animation GIF Strasbourg ICU
Hourly comfort levels during the first week of the year.
Projects

Paris Est train station

Roofing and design variations: influence on interior thermal comfort

The study of comfort levels in the Paris Est train station development project was conducted using several steps / methods:

  • A coupling between CFD and dynamic thermal simulation for the calculation of natural ventilation with accurately calculated pressure coefficients
  • The detailed internal distribution of solar fluxes with Radiance software
  • Obtaining indoor comfort levels hour by hour for the whole year and their statistical analysis.

Some graphic results below.

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Projects

Lyon Part Dieu train station

Study of the indoor distribution of thermal comfort

The comfort level study was conducted using several steps / methods:

  • A coupling between CFD and dynamic thermal simulation for the calculation of natural ventilation with accurately calculated pressure coefficients
  • The detailed internal distribution of solar fluxes with Radiance software
  • Obtaining indoor comfort levels, hour by hour, for the whole year usinga metamodel in order to speed up the calculations on this very large model.

The result in pictures!

Perspective du projet (vue d’architecte).

Aperçu du site dans son environnement urbain, utilisé pour le calcul CFD.

Météorologie du site de Lyon-Part-Dieu prenant en compte l’effet d’îlot de chaleur urbain (ICU)

Pourcentage du temps en zone de confort (indicateur OTCA).

Niveau de confort P.E.T. en moyenne annuelle.

Distribution du champ des vitesses moyen en intérieur.

Distribution moyenne de la température radiante.

Projects

Paris Austerlitz train station

Annual modelling of indoor spatial comfort in Paris Austerlitz train station

A study on possible variants for the improvement of the summer and winter comfort of the main hall, implementing the following phases:

  • A CFD/BEM coupling for the calculation of natural ventilation with the right pressure coefficients
  • Le calcul détaillé des flux solaires en intérieur avec Radiance
  • Determining indoor comfort levels on an hour-by-hour basis throughout the year

Projects

Paris Gare de l'Est train station

Annual indoor spatial comfort study

A study on possible variants for the improvement of summer and winter comfort of the side halls as well as the transverse platform implementing :

  1. A CFD/BES coupling with solar fluxes for the indoor spatial comfort levels computation,
  2. A sensitivity analysis with the Morris method, on comfort objective to determine the most relevant leverages
  3. The use of genetic optimization in order to obtain the sets of parameters that maximize summer and winter comfort.

Below is an animation about the evolution of comfort levels during genetic optimization, according to the "growth" of generations:

Genetic optimization: optimal solutions evolution over generations

 

Each "dot" that appears corresponds to a complete comfort study (point 1 above) and each color change corresponds to a new generation. The objective of genetic optimization is to find the best compromise between summer and winter comfort (Pareto front).

Projects

Nice Saint-Roch – New maintenance and storage facility

Feasibility of cooling by natural ventilation for the administrative premises as part of the "AZUR Technicentre" project in Nice Saint Roch:

  • Calculation of pressure coefficients on façades over a full year using CFD,
  • Simulation Thermique du Bâtiment enrichie des résultats CFD,
  • Comfort assesment (number of hours above 28°C) for a typical year (2018)
  • Comfort Assesment for a 2050 climatic scenario : HadOM3 & HadAM3 models + RCP scenrios from IPCC (Intergovernmental Panel on Climate Change)