One-dimensional ablation using Landau transformation and finite control volume procedure

In this study, a mathematical and numerical modeling of the photovoltaic (PV)-thermal solar system to power the multistage flashing chamber process is presented. The proposed model was established after the mass and energy conservation equations written for finite control volume were integrated with properties of the water and nanofluids. The nanofluids studied and presented herein are Ai2O3, CuO, Fe3O4, and SiO2. The multiple flashing chamber process was studied under various conditions, including different solar radiation levels, brine flows and concentrations, and nanofluid concentrations as well as flashing chamber temperatures and pressures. Solar radiation levels were taken as 500 w/m2, 750 w/m2, 1000 w/m2, and finally, 1200 w/m2. The nanofluid volumetric concentrations considered varied from 1% to 20%. There is clear evidence that the higher the solar radiation, the higher the flashed flow produced. The results also clearly show that irreversibility is reduced by using nanofluid Ai2O3 at higher concentrations of 10% to 20% compared to water as base fluid. The highest irreversibility was experienced when water was used as base fluid and the lowest irreversibility was associated with nanofluid SiO2. The irreversibility increase depends upon the type of nanofluid and its thermodynamic properties. Furthermore, the higher the concentration (e.g., from 10% to 20% of Ai2O3), the higher the availability at the last flashing chamber. However, the availability is progressively reduced at the last flashing chamber. Finally, the predicted results compare well with experimental data published in the literature.

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Thermal Model of a PC

Journal of Electronic Packaging ◽

10.1115/1.2905501 ◽

1994 ◽

Vol 116 (2) ◽

pp. 134-137 ◽

Cited By ~ 16

Author(s):

Ronald L. Linton ◽

D. Agonafer

Keyword(s):

Thermal Model ◽

Control Volume ◽

Turbulent Viscosity ◽

Flow Distribution ◽

Electronic Packages ◽

Air Flow Rate ◽

Simulation Code ◽

Alternative Approach ◽

Finite Control ◽

Turbulence Effects

This paper presents an alternative approach to modeling box cooling in electronic packages. A finite-control-volume simulation code is used to simulate an IBM desktop Personal Computer. Only the geometry, the overall air flow rate, the turbulent viscosity and the power dissipations from each card must be specified. The simulation code predicts the flow distribution inside the PC, the convection coefficients, the turbulence effects, and the temperatures. Predicted component temperatures were compared to measured values.

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Raised Floor Computer Data Center: Effect on Rack Inlet Temperatures When Adjacent Racks Are Removed

2003 International Electronic Packaging Technical Conference and Exhibition, Volume 2 ◽

10.1115/ipack2003-35240 ◽

2003 ◽

Cited By ~ 6

Author(s):

Roger Schmidt ◽

Ethan Cruz

Keyword(s):

Data Center ◽

Control Volume ◽

Fluid Dynamic ◽

Computer Code ◽

Cfd Model ◽

Computer Data ◽

Center Effect ◽

Air Temperatures ◽

Baseline Case ◽

Finite Control

This paper focuses on the effect on inlet rack air temperatures when adjacent racks are removed. Only the above floor (raised floor) flow and temperature distributions were analyzed for various air flowrates exhausting from the perforated tiles and the rack. A Computational Fluid Dynamic (CFD) model was generated for the room with electronic equipment installed on a raised floor with particular focus on the effects on rack inlet temperatures of these high powered racks. The baseline case was with forty racks of data processing (DP) equipment arranged in rows in a data center cooled by chilled air exhausting from perforated floor tiles. The chilled air was provided by four A/C units placed inside a room 12.1 m wide × 13.4 m long. Since the arrangement of the racks in the data center was symmetric only one-half of the data center was modeled. To see the effect of missing racks adjacent to high powered racks various configurations were analyzed. The numerical modeling was performed using a commercially available finite control volume computer code called Flotherm (Trademark of Flomerics, Inc.). The flow was modeled using the k-e turbulence model. Results are displayed to provide some guidance on the design and layout of a data center.

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Numerical Simulation of Fluid Flow and Heat Transfer in the Micro-Nozzle

Heat Transfer, Part B ◽

10.1115/imece2005-82464 ◽

2005 ◽

Author(s):

Longjian Li ◽

Yihua Zhang ◽

Wenzhi Cui ◽

Tien-Chien Jen ◽

Qinghua Chen ◽

...

Keyword(s):

Heat Transfer ◽

Control Volume ◽

Slip Model ◽

Control Volume Method ◽

Propulsion Performance ◽

Micro Nozzle ◽

Flow And Heat Transfer ◽

Finite Control ◽

Mems Technology ◽

Volume Method

Micro-nozzle, based on the MEMS technology, has played an important role in orbit positioning, attitude adjusting and other applications of micro-satellites. The continuous no-slip model of two-dimensional compressible laminar flow in the micro-nozzle was proposed and solved numerically by finite control volume method. The flow and heat transfer in the micro-nozzle were computed under different conditions, including different inlet pressures, different inlet temperatures and different divergent angles. Flow field and effects of these conditions on the propulsion performance were analyzed. Finally, simulated solutions were compared and validated with the experimental results.

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