In physical engineering, the turbulent flow on the surface roughness is very important. The roughness of the surface changed the distance of the interval. The roughness coefficient occurred with increasing turbulence intensities was stronger. The turbulence intensity away from the roughness in the shape was zero. The variation of turbulence intensity at the experimental flow conditions change was not affected.

Abstract
 1. 서론
 2. 실험
 3. 유동가시화
 4. 결론
 References

• 조대환(Mok-po maritime univ.) | Dae-Hwan Cho
• 정하균(Chungbuk provincial college) | Ha-Gyoon Jung Corresponding Author
• 심의보(Mok-po maritime univ.) | Bui-bo Shim