A predictive formula for the Nusselt number of compressible laminar fluid flow passing the thermal developing zone of a hot tube

2019 ◽  
Vol 48 (4) ◽  
pp. 1529-1543 ◽  
Author(s):  
Bahador Abolpour ◽  
Rahim Shamsoddini
Keyword(s):  
Nusselt Number ◽  
Fluid Flow ◽  
Laminar Fluid Flow

scholarly journals NUMERICAL INVESTIGATION OF DEVELOPING LAMINAR FLUID FLOW THROUGH RECTANGULAR ANNULUS DUCT

2020 ◽  
Vol 15 (12) ◽  
Author(s):  
Takwah Talib Hasan
Keyword(s):  
Heat Flux ◽  
Nusselt Number ◽  
Fluid Flow ◽  
Average Nusselt Number ◽  
Constant Heat Flux ◽  
Ansys Fluent ◽  
Constant Length ◽  
Laminar Fluid Flow ◽  
Number Increase ◽  
Flow Through

The laminar fluid flow of water through the annulus duct was investigated numerically by ANSYS fluent version 15.0 with height (2.5, 5, 7.5) cm and constant length (L=60cm). With constant heat flux applied to the outer duct. The heat flux at the range (500,1000,1500,2000) w/m2 and Reynolds number values were ≤ 2300. The problem was 2-D investigated. Results revealed that Nusselt number decrease and the wall temperature increase with the increase of heat flux. Also, the average Nusselt number increase as Re increases. And as the height of the annulus increase, the values of the temperature and the local and average Nusselt number increase.

LAMINAR FLUID FLOW AND HEAT TRANSFER CHARACTERISTICS OF WAVY MICROCHANNELS WITH WALL PHASE SHIFT

2018 ◽  
Author(s):  
Angshuman Bhardwaj ◽  
Mithun Krishna P. M ◽  
Deepu M ◽  
Shine S. R
Keyword(s):  
Heat Transfer ◽  
Fluid Flow ◽  
Phase Shift ◽  
Heat Transfer Characteristics ◽  
Laminar Fluid Flow ◽  
Transfer Characteristics ◽  
Flow And Heat Transfer

Numerical study of laminar fluid flow in a curved elliptic duct with internal fins

2008 ◽  
Vol 29 (2) ◽  
pp. 540-544 ◽  
Author(s):  
P.K. Papadopoulos ◽  
P.M. Hatzikonstantinou
Keyword(s):  
Fluid Flow ◽  
Numerical Study ◽  
Laminar Fluid Flow ◽  
Internal Fins

Laminar Fluid Flow Around Two Wall-Mounted Blocks of Different Size

2009 ◽  
Author(s):  
Mohammad Mehdi Tavakol ◽  
Mohammad Eslami
Keyword(s):  
Fluid Flow ◽  
Free Stream ◽  
Three Dimensional ◽  
Simple Algorithm ◽  
Bluff Bodies ◽  
Wake Region ◽  
Science And Engineering ◽  
Vortical Structures ◽  
Laminar Fluid Flow ◽  
Pressure Distributions

Fluid flow around single or multiple bluff bodies mounted on a surface has great significance in science and engineering. Understanding the characteristics of different vortices formed around wall-mounted bodies is quite necessary for different applications. Although the case of a single surface mounted cube has been studied extensively, only little attention has been paid to the flow around two or more rectangular blocks in array. Therefore, a CFD code is developed to calculate three dimensional steady state laminar fluid flow around two cuboids of arbitrary size and configuration mounted on a surface in free stream conditions. The employed numerical scheme is finite volume and SIMPLE algorithm is used to treat pressure and velocity coupling. Results are presented for two rectangular blocks of the different size mounted on a surface in various inline arrangements. Streamlines are plotted for blocks of different size ratio. Velocity and pressure distributions are also plotted in the wake region behind the obstacles. It is shown that how the behavior of flow field and vortical structures depend on the respective size and location of the larger block in comparison with the case of two inline wall mounted cubes of the same size.

Laminar Forced Convection in Annular Microchannels With Slip Flow Regime

2009 ◽  
Author(s):  
Arman Sadeghi ◽  
Abolhassan Asgarshamsi ◽  
Mohammad Hassan Saidi
Keyword(s):  
Nusselt Number ◽  
Fluid Flow ◽  
Aspect Ratio ◽  
Boundary Conditions ◽  
Knudsen Number ◽  
Gas Flow ◽  
Slip Flow ◽  
Outer Wall ◽  
Graphical Form ◽  
Uniform Temperature

Fluid flow and heat transfer at microscale have attracted an important research interest in recent years due to the rapid development of microelectromechanical systems (MEMS). Fluid flow in microdevices has some characteristics which one of them is rarefaction effect related with gas flow. In this research, hydrodynamically and thermally fully developed laminar rarefied gas flow in annular microducts is studied using slip flow boundary conditions. Two different cases of the thermal boundary conditions are considered, namely: uniform temperature at the outer wall and adiabatic inner wall (Case A) and uniform temperature at the inner wall and adiabatic outer wall (Case B). Using the previously obtained velocity distribution, energy conservation equation subjected to relevant boundary conditions is numerically solved using fourth order Runge-Kutta method. The Nusselt number values are presented in graphical form as well as tabular form. It is realized that for the case A increasing aspect ratio results in increasing the Nusselt number, while the opposite is true for the case B. The effect of aspect ratio on Nusselt number is more notable at smaller values of Knudsen number, while its effect becomes slighter at large Knudsen numbers. Also increasing Knudsen number leads to smaller values of Nusselt number for the both cases.

scholarly journals Natural convection in a differentially heated enclosure with triangular roof

1970 ◽  
Vol 39 (1) ◽  
pp. 1-7 ◽  
Author(s):  
Sumon Saha ◽  
Noman Hasan ◽  
Chowdhury Md Feroz
Keyword(s):  
Heat Transfer ◽  
Nusselt Number ◽  
Fluid Flow ◽  
Natural Convection ◽  
Average Nusselt Number ◽  
Numerical Study ◽  
Convection Heat Transfer ◽  
Element Analysis ◽  
Left Wall ◽  
Square Enclosure

A numerical study has been carried out for laminar natural convection heat transfer within a two-dimensional modified square enclosure having a triangular roof. The vertical sidewalls are differentially heated considering a constant flux heat source strip is flush mounted with the left wall. The opposite wall is considered isothermal having a temperature of the surrounding fluid. The rest of the walls are adiabatic. Air is considered as the fluid inside the enclosure. The solution has been carried out on the basis of finite element analysis by a non-linear parametric solver to examine the heat transfer and fluid flow characteristics. Different heights of the triangular roof have been considered for the present analysis. Fluid flow fields and isotherm patterns and the average Nusselt number are presented for the Rayleigh numbers ranging from 103 to 106 in order to show the effects of these governing parameters. The average Nusselt number computed for the case of isoflux heating is also compared with the case of isothermal heating as available in the literature. The outcome of the present investigation shows that the convective phenomenon is greatly influenced by the inclined roof height. Keywords: Natural convection, triangular roof, Rayleigh number, isoflux heating. Doi:10.3329/jme.v39i1.1826 Journal of Mechanical Engineering, vol. ME39, No. 1, June 2008 1-7

scholarly journals Numerical simulation of incompressible laminar fluid flow in tubes with wire coil inserts

2008 ◽  
Author(s):  
D. Muñoz-Esparza ◽  
J. Pérez-García ◽  
E. Sanmiguel-Rojas ◽  
A. García-Pinar ◽  
J. P. Solano-Fernández
Keyword(s):  
Numerical Simulation ◽  
Fluid Flow ◽  
Laminar Fluid Flow ◽  
Wire Coil

Boiling heat transfer characteristics of binary magnetic fluid flow in a vertical circular pipe with a partly heated region

2004 ◽  
Vol 218 (2) ◽  
pp. 223-232 ◽  
Author(s):  
S Shuchi ◽  
K Sakatani ◽  
H Yamaguchi
Keyword(s):  
Magnetic Field ◽  
Heat Transfer ◽  
Nusselt Number ◽  
Fluid Flow ◽  
Boiling Heat Transfer ◽  
Transfer Rate ◽  
Heated Region ◽  
Heat Transfer Characteristics ◽  
Transfer Characteristics ◽  
The Magnetic Field

An investigation was conducted for heat transfer characteristics of binary magnetic fluid flow in a partly heated circular pipe experimentally. The boiling heat transfer characteristics on the effects of the relative position of the magnetic field to the heated region were particularly considered in the present study. From the experimental verification, the Nusselt number, representing boiling heat transfer characteristics, was obtained for various flow and magnetic conditions which were represented by the non-dimensional parameters of the Reynolds number and the magnetic pressure number. Additionally, the rate of change of the Nusselt number found by applying the magnetic field was also estimated and the optimal position of the field to the partly heated region was discussed. The results indicated that the effect of the magnetic field to the heat transfer rate from the heated wall was mainly subjected to the effect of the vortices induced in the magnetic field region and the possibility of controlling the heat transfer rate by applying an outer magnetic field to utilize the effect.

Sign in / Sign up

Export Citation Format

Share Document