Building Engineering

Examples and Applications

The association of ENGYS with the Architecture, Engineering and Construction (AEC) sector has grown considerably since the first launch of our open-source CFD software products HELYX and HELYX-Hydro. This growth has coincided with a continous increase in the demand for more powerful, fit-for-purpose and cost-effective CFD methods to solve the very challenging design problems faced by engineers operating in the AEC sector.

Our customers in this industry range from world-renowned architecture firms to large engineering consultancy companies. The main applications solved with HELYX in the ambit of AEC include: wind loads, wind predictions, urban comfort, HVAC, fire safety, rain management and hydraulic structures, among others.

Environmental Analysis

HELYX is provided with the necessary tools to mesh and analyse the flow conditions in built environments at city scales. The automatic hex-dominant meshing technology in HELYX enables users to generate high-fidelity models with minimum geometry preparation and cleaning.

Wind assessment predictions are performed by simulating multiple wind directions around the building or structure of interest, starting from a wind rose frequency distribution. The atmospheric boundary layers can be approximated (where required) with our specialised turbulent inlet boundary condition. The results from all wind directions are used to calculate an annualised exceedance probability based on a specific wind speed limit.

When combined with temperature, humidity transport and solar radiation load, the wind velocities can also be used to calculate the UTCI (Universal Thermal Comfort Index) to provide a sense of human comfort at these very large scales.

Our users also perform wind driven rain deposition studies using our Euler-Euler multi-phase flow solver in conjunction with the methods described above.

Building Analysis

The flow-related problems in buildings solved by or customers using HELYX are plentiful. The characteristics of the simulations and the methods employed depend largely on the type of application.

HVAC simulations involving multiple air flow inlets and outlets, diffusers, fans, thermal effects and solar radiation, humidity and contaminants transport are common for most office buildings, classrooms and data centers. Human comfort is assessed using a wide range of standard comfort metrics provided with HELYX, including PMV, PPD and other local thermal comfort criteria. Our special boundary condition for group of humans are employed to model the thermal loads, humidity and CO2 originating from a large number of people in a given space, such as a theatre or stadium.

Similar CFD methods are also be applied to model smoke propagation in buildings and public spaces in case of a fire, such as parking lots, tunnels and underground stations. The effects of moving trains and other moving structures are considered with the mesh motion algorithms available in our code.

Hydraulic Structures

ENGYS works with some of the largest hydraulic engineering specialists and construction companies in the world. The two-phase VOF flow solvers available in HELYX and HELYX-Hydro are employed to design and assess the performance of all kinds of hydraulic structures. The applications include dams, fishways, pump stations, culverts and waterways, barrages, water supplies and treatment plants, among others. The multi-phase flow methods are often combined with wave models available in HELYX to predict the forces induced by wave impacting the structures.

For mitigating wind induced vibrations in slender buildings, Tuned Liquid Column Dampers (TLCD) are employed to increase the damping characteristics of the structure. The sloshing flow in the TLCD is modelled using our two-phase VOF solvers in combination with a rigid-body mesh motion algorithm. This methodology has been validated by comparing the CFD results to the equivalent scale model of a TLCD tested on a shake table. The TLCD is dimensioned and tested in full scale using HELYX.

Free-surface vortex formation in Serpentine Road water treatment pump station (courtesy of Parsons Brinckerhoff Australia).


Contact your nearest ENGYS office today to discuss your specific applications with one of our engineers and learn more about how we can help you realise your designs using our open-source CFD software products and services.