Published: Nov. 11, 2020 By

Data Center

Originating from the computer game industry, Fast Fluid Dynamics (FFD) is a faster alternative to Computational Fluid Dynamics (CFD) used for fluid flow simulation. Dr. Zuo developed the FFD model for indoor environment modeling in his Ph.D. thesis "Advanced Simulations of Air Distributions in Buildings" at Purdue University. Since then, he and many other researchers have extended the FFD model for both indoor and outdoor airflow simulation. This page summarizes the development of FFD model by the SBS Lab over the years.

  • Data Center Airflow Management: 

The FFD model is tailored for data center computer room airflow management with new modules added for data center applications. The figure on the right shows temperature contours of an example data center with varying supply flow air ratio produced by FFD simulations. The air ratio is defined as the ratio of the total supply flowrate to the total IT flowrate. It can be seen a high air ratio overcools the data center, but too low of an air ratio can lead to unwanted hot spots. The source code is publicly available here. It is also publicaly released in the Modelica Buildings library to support the coupled simulation of indoor airflow and HVAC systems. The FFD model is already adopted by Schneider Electric in their commerical data center tools. The research is described in this paper: X. Han, W. Tian, J. VanGilder, W. Zuo, C. Faulkner 2021. "An Open Source Fast Fluid Dynamics Model for Data Center Thermal Management." Energy and Buildings, 230, pp. 110599.

  • Coupled Simulation of Indoor Environment and Building HVAC and Control System:

A detailed room model was implemented in the open source Modelica Buildings library to enable the coupling of FFD with Modelica. This coupled model enables the co-simulation of airflow and HVAC system to study the optimal design and control of indoor environment. The coupled models are available at the Modelica Buildings library website. The research is described in this paper: W. Zuo, M. Wetter, W. Tian, D. Li, M. Jin, Q. Chen 2016. "Coupling Indoor Airflow, HVAC, Control and Building Envelope Heat Transfer in the Modelica Buildings Library.” Journal of Building Performance Simulation, 9(4), pp. 366-381.

Building Airflow

  • Simulation of Outdoor Airflow Around Buildings:

FFD was compared to CFD for its ability to simulate natural ventilation in buildings, an important application to saving energy in buildings. The results showed that FFD could predict wind-driven and buoyancy-driven ventilation with reasonable accuracy. The figure on the right shows the velocity contours predicted by CFD (left) and FFD (right) for wind-driven ventilation around a group of buildings, where the prevailing wind is from the southwest direction (lower-left in the figure). The flow upstream is similar between the two, however discrepancies are present for the wake region behind the buildings. This research is described in this paper: M. Jin, W. Zuo, Q. Chen 2013. "Simulating Natural Ventilation in and Around Buildings by Fast Fluid Dynamics." Numerical Heat Transfer, Part A: Applications, 64(4), pp. 273-289.

  • Cross-platform Parallel Computing for Indoor Airflow Simulation:

Dr. Zuo implemented our first parallel verion of FFD in CUDA on a NVIDA GPU in 2009 and achieved 30 times speedup. Our latest parallel version of FFD code was implemented in OpenCL, which is a cross-platform parallel computing language. This code can perform parallel computing on multiple different CPUs or GPUs and achieved up to 1,000 times speedup as described in this paper: W. Tian, T. A. Sevilla, W. Zuo 2017. “A Systematic Evaluation of Accelerating Indoor Airflow Simulations Using Cross Platform Parallel Computing.” Journal of Building Performance Simulation, 10(3), pp. 243-255.

Game Style Demo of FFD Code

A game style demo of mixed convection flow in an empty room was created. Like playing a computer game, this interactive demo allows users to change supply airflow rate and floor temperature, add contaminants into the space and observe the transmission of the contaminants. This demo can be downloaded here. The results have been validated in our paper: W. Zuo, Q. Chen 2009. "Real Time or Faster-than-Real-Time Simulation of Airflow in Buildings." Indoor Air, 19 (1), pp. 33-44.

Related Journal Papers:

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