Top > Application Examples > Tohoku Institute of Technology

Application Examples

Tohoku Institute of Technology
Transforming Strong Winds to Gentle Breezes:
The Relationship between Wind Minimization, Wind Turbines, and CFD

[Vol. 2] Mr. Toshikazu Nozawa, the Research Associate at the Tohoku Institute of Technology (Picture 1), has been investigating wind minimization and power-generating wind turbines. Both are possible alternatives for windbreak trees lost in the tsunami that struck northeastern Japan in 2011. Here, Mr. Nozawa explains his research pursuits and his use of CFD (Computational Fluid Dynamics) in his work.

Picture 3: Mr. Toshikazu Nozawa, Research Associate, Tohoku Institute of Technology

The Relationship between CFD and Experiments

Mr. Nozawa uses CFD simulations during the research and development of his wind turbines. Using simulations, he can validate the effects of phenomenon that cannot be tested in experiments. For example, this includes adding anemometers inside turbines. “Simulations are helpful in a number of ways. We can check the flow qualitatively before wind tunnel experiments. CFD helps us understand the factors that cannot be clearly identified in the actual experiments” says Mr. Nozawa.

“From the experience, I now think that it is best to apply CFD simulations when evaluating ‘what is missing’ and ‘what are the important parameters.’ Boundary conditions and parameters can be adjusted one by one,” says Mr. Nozawa.

In this research, Mr. Nozawa uses CFD simulations to understand how the wind turbine weakens the strength of the wind. In fluid engineering, many phenomena are yet to be fully analyzed. According to Mr. Nozawa, weakening the wind by using wind turbines is one of them.

As Mr. Nozawa is essentially an experimentalist, he first considered CFD simulations as a means of estimating results prior to conducting experiments. “I once conducted a wind tunnel experiment to represent snow drifts by supplying snow-like particles. I ended up with a huge difference between experimental results and actual phenomena because of the error I made when setting some of the conditions,” recalls Mr. Nozawa. At that time, he recognized that both wind tunnel experiments and CFD simulations were capable of qualitatively estimating the effects, but neither was capable of quantitatively predicting the actual phenomena. Now, his view has changed.

“Ask for help rather than try to do something you are not good at. That’s my principle,” says Mr. Nozawa. Software Cradle has participated in Mr. Nozawa’s research by providing analytical support. “In this way I could focus on what I’m good at, and that helped me make fast and efficient progress on my research. Some interesting ideas came from Software Cradle engineers who had different views,” says Mr. Nozawa.

Tackling wind minimization was a new challenge for Software Cradle engineers. Mr. Nozawa made it more challenging by asking them to accurately represent the phenomena, where the turbine rotates by means of the lift force created from winds, rather than being rotated at a given speed and wind is applied as an inflow condition. Despite the challenge, Mr. Nozawa and Software Cradle successfully represented the phenomena using CFD simulations.

Ways to use CFD Simulation Results and the Benefits

When Mr. Nozawa’s project was featured on a Japanese TV program, some of the CFD analysis results were used to illustrate the wind-minimizing effect in a way audience could easily understand. “It’s striking to see the visualized analysis results of winds, which are normally invisible. We used some of the visualization results from the analyses performed by Software Cradle. Many in the audience responded positively after the show. These visualized images helped them understand the phenomena. Visualizing results is beneficial for researchers, too. We know the qualitative flow before the wind tunnel experiments are performed, and we can also identify effects that cannot be evaluated in experiments,” says Mr. Nozawa.

Mr. Nozawa considers each result from wind tunnel experiments and CFD simulations as just one outcome for a certain condition. “In the end, the physics behind the natural wind environment is all there is. I think the technology needed to control strong winds will progress drastically if we can simulate natural phenomena by synergistically using wind tunnel experiments and CFD simulations,” says Mr. Nozawa.

Fig 4: SC/Tetra was used to simulate the effects of wind minimizing equipment. Color bar indicates magnitude of velocity (m/s).

CFD as a Means to Provide Comfort

Mr. Nozawa predicts there will be changes to CFD applications in the environmental and energy fields. “I’m hoping to see various applications that help improve the level of comfort. For example, it would be nice if we could put various manufacturers’ wind power generators on the roof of a building, click an ‘estimate power generation’ icon and instantly estimate the annual power generation based on the wind speed and direction at the location. Then one could purchase the electricity accordingly. Or, if we could install the wind-minimizing, power-generating turbine system, we would be able to instantly find out how weak the wind would become just by clicking a ‘wind environment’ icon,” explains Mr. Nozawa.

hroughout his research, Mr. Nozawa explores ways to convert strong winds to pleasant breezes and provide a comfortable environment. He expects the significance of CFD, as a tool to help deliver improved safety, reliability, and comfort, will grow even more.

​​*All product and service names mentioned are registered trademarks or trademarks of their respective companies.
*Contents and specifications of products are as of February 1, 2015 and subject to change without notice. We shall not be held liable for any errors in figures and pictures, or any typographical errors in this brochure.

Company Details


Tohoku Institute of Technology
Founded 1964
Type of university Private
Location Taihaku-ku, Sendai, Japan (Yagiyama campus)/td>



This article is also available in pdf.


Featured Software


General Purpose Unstructured Mesh Thermal-fluid Analysis System
More Details

Visitors also read


Aomori Prefectural Industrial Technology Research Center

- Thermal Analysis is Beneficial for the Design of Food Contaminant Scanners - Usability was a Deciding Factor in Choosing HeatDesigner for the Analysis Tool

  • 熱設計PAC

Hitachi Mito Engineering Co., Ltd.

- Real-time Solutions for Thermal Problems - Key to Success is a Workplace Environment Where Design Engineers Can Promptly Implement Their Ideas

  • 熱設計PAC

Nikken Sekkei Ltd

Assisting Architectural Designs with a Variety of Simulations Using scSTREAM



Making the Most of CFD Analysis by Effective Coordination with BIM



Contact us from the inquiry form below for any inquiry regarding this article.