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Convective heat transfer around vertical jet fires: an experimental study
Bulent Kozanoglu1, Luis Zárate, Mercedes Gómez-Mares
1Universidad de las Américas, Puebla, Mexico. bulentu.kozanoglu@udlap.mx
Journal of Hazardous Materials
|October 4, 2011
Summary
This study analyzed convection heat transfer in vertical jet fires. Higher flame lengths increase heat transfer, with Nusselt number correlating positively with Rayleigh, Reynolds, and Froude numbers.
Area of Science:
- Fluid Dynamics
- Heat Transfer
- Combustion Science
Background:
- Vertical jet fires involve complex turbulent combustion and heat transfer phenomena.
- Understanding convection heat transfer is crucial for fire safety and design.
Purpose of the Study:
- To experimentally investigate convection heat transfer in vertical jet fires.
- To develop correlations for heat transfer coefficients based on dimensionless numbers.
Main Methods:
- Experimental analysis of turbulent propane flames in subsonic and sonic regimes.
- Application of the solid flame model to calculate convection heat transfer coefficients.
- Development of dimensionless equations relating heat transfer to flow parameters.
Main Results:
- Convection heat transfer rate increases with increasing flame length.
- Nusselt number shows a positive correlation with Rayleigh and Reynolds numbers.
- For subsonic flames, Nusselt number increases with Froude number and orifice diameter.
Conclusions:
- Flame length is a key factor influencing heat transfer in vertical jet fires.
- Dimensionless parameters effectively describe convection heat transfer in these fires.
- The developed equations provide a basis for predicting heat transfer in vertical jet fire scenarios.
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