Numerical Analysis of Flow across Brush Elements Based on a 2-D Staggered Tube Banks Model

Abstract

In order to improve efficiency in turbomachinery, brush seal replaces labyrinth seals widely in the secondary air system. A 2-d staggered tube bank model is adopted to simulate the gas states and the pressure character in brush seal, and computational fluid dynamics (CFD) is used to solve the model in this paper. According to the simulation results, the corrected formula of the Euler number and dimensionless pressure are given. The results show that gas expands when flow through the bristle pack, and the gas expansion closes to an isotherm process. The dynamic pressure increases with decreasing static pressure. The Euler number can reflect the seal performance of brush seals in leakage characteristics. Compared with increasing the number of rows, the reduction of the gap is a higher-efficiency method to increase the Euler number. The Euler number continually increases as the gap decreases. However, with the differential pressure increasing, Euler number first increases and then decreases as the number of rows increases. Finally, the pressure distribution on the surface of end rows is asymmetric, and it may increase the friction between the bristles and the back plate.

Thermal Performance of Staggered Bare Tube Bank Heat Exchanger as Air Pre-Heater for Seaweed Convective Dryer

“…If the staggered bare tube bank heat exchanger satisfies the inequality above, then the maximum speed occurs in the diagonal plane (AD). Therefore, the maximum speed in the diagonal plane can be previously estimated using equation ( 2), which is quoted from [47]: On the other hand, bare staggered tube banks do not satisfy the inequality above, so the maximum speed occurs in the transverse plane (AT), so the maximum air speed in the transverse plane is estimated using equation ( 3), which is quoted from [58,102]:…”

“…Facts show that more than 50% of the energy used is wasted as waste heat that can be used as an energy source [47], [50], [51]. Waste heat recovery energy conservation technology equipment, one of which is a heat exchange [47], where the type of heat exchanger is a plate heat exchanger [52][53][54][55], tube bank heat exchanger [56][57][58][59][60][61], shell and helical coil heat exchangers [62][63][64][65][66][67][68][69], shell and tube heat exchangers [70][71][72][73], dan shell and serpentine tube heat exchangers [74][75][76][77][78].…”

Analisis Kinerja Termal Penukar Kalor Tube Bank Bare in-Line Aliran Silang Sebagai Pemulihan Limbah Panas Pengering Konvektif Rumput Laut

“…Jika tube bank bare in-line tidak memenuhi pertidaksamaan di atas, maka kecepatan maksimum terjadi pada bidang tranversal (AT). Oleh karena itu, kecepatan yang disuplai pada saluran masuk dapat dihitung menggunakan persamaan (2) yang diperoleh dari [50], [89]:…”

Temperature Field and Performance Analysis of Brush Seals Based on FEA-CFD and the Porous Medium of Anisotropic Heat Transfer Models

“…Jagjiwanram [30] studied the effective thermal conductivity of the two-dimensional porous medium, and it was observed that β, which is the angle between the direction of heat flow and the plane skeleton layer, is an essential factor for k e . k e is indicated in Equation (10).…”

“…The tube bank model assumes that the air travels through the closely arranged staggered-array tube bank, and two sub-models are included: 2-dimensional and 3-dimensional tube bank models. The 2-dimensional model cannot reflect the anisotropic flow in the bristle pack [10], and a 3-dimensional model [11] is too complex for establishing a model and solving computational convergence. The bristles closely resemble a random arrangement, and the tube bank model has limitations.…”