Heat transfer gradient through the reactor

1
Heat transfer gradient through the reactor

• Yan Vasudha

EGEE 520 project presentation
Dec 1 2005
2
Introduction
2

• Steel

Al2O3
Air
3
5
9
11
7
Glass reactor
1
12
Fuel
2
4
6
8
10
3
Governing equations
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k thermal conductivity (Wm-1K-1) A
cross-sectional area (m2) dT/dn temperature
gradient (Km-1)
Conduction
Convection
h heat transfer coefficient (Wm-2K-1) Tsolid
temperature at the surface of the solid body
(K) Tfluid ambient or remote temperature of the
fluid (K)
Radiation
eSB Stefan-Boltzman constant (Wm-2K-4) s
emissivity of the surface Tsolid temperature at
the boundary of the solid body (K) T8 ambient
temperature (K)
Partial differential equation for heat
conduction
4
4
Formulation
Initial assumptions Steady-state process Axial
symmetry (2D) Modes Convection and Conduction
Incompressible Navier-Stokers
Subdomain and Boundary settings in FEMlab
5
5
Solution
Temperature distribution with flow rate 0.01mL/s
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6
Validation
Heat gained by fluid when it passes through the
reactor
q 7.895 W/m3
Heat transfer through radial conduction in
cylindrical wall
q 9.7596 W/m3
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Parametric Study
Temperature distribution with flow rate 0.001mL/s
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8
Parametric Study
Temperature distribution with flow rate 0.1mL/s
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9
Conclusion
When the flow rate of fuel is high, temperature
distribution is roughly symmetric with z 0. The
temperature of fuel is almost constant (293 K)
except in two bottoms. When the flow rate of
fuel is decreased, the temperature of fuel
increases. Temperature distributions within
Al2O3 and steel almost maintain the same no
matter what the flow rate is. However, the
temperature distribution within air changes with
changing flow rate. FEMlab is a useful tool for
simulation of heat transfer process, and the
results of our modeling are reasonable.
10
Questions?