A Study on Velocity Profiles between Two Baffles in a Horizontal Circular Tube
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The shell and tube heat exchanger is an essential part of a power plant for recovering transfer heat between the feedwater of a boiler and the wasted heat. The baffles are also an important element inside the heat exchanger. Internal materialsinfluence the flow pattern in the bed. The influence of baffles in the velocity profiles was observed using a three-dimensionalPIV (Particle Image Velocimetry) around baffles in a horizontal circular tube. The velocity of the particles was measured beforethe baffle and between them in the test tube. Results show that the velocity vectors near the front baffle flow along the vertical wall, and then concentrate on the upperopening of the front baffle. The velocity profiles circulate in the front and rear baffle. These profiles are related to theReynolds number (Re) or the flow intensity. Velocity profiles at lower Re number showed complicated mixing to obtain thevelocities and concentrate on the lower opening of the rear baffle as front wall. Numerical simulations were performed to investigate the effects of the baffle and obtain the velocity profiles between thetwo baffles. In this study, a commercial CFD package, Fluent 6.3.21 with the turbulent flow modeling, k-ε are adopted. Thepath line and local axial velocities are calculated between two baffles using this program.
Abstract
The shell and tube heat exchanger is an essential part of a power plant for recovering transfer heat between the feedwater of a boiler and the wasted heat. The baffles are also an important element inside the heat exchanger. Internal materialsinfluence the flow pattern in the bed. The influence of baffles in the velocity profiles was observed using a three-dimensionalPIV (Particle Image Velocimetry) around baffles in a horizontal circular tube. The velocity of the particles was measured beforethe baffle and between them in the test tube. Results show that the velocity vectors near the front baffle flow along the vertical wall, and then concentrate on the upperopening of the front baffle. The velocity profiles circulate in the front and rear baffle. These profiles are related to theReynolds number (Re) or the flow intensity. Velocity profiles at lower Re number showed complicated mixing to obtain thevelocities and concentrate on the lower opening of the rear baffle as front wall. Numerical simulations were performed to investigate the effects of the baffle and obtain the velocity profiles between thetwo baffles. In this study, a commercial CFD package, Fluent 6.3.21 with the turbulent flow modeling, k-ε are adopted. Thepath line and local axial velocities are calculated between two baffles using this program.
참고문헌 (14)
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