Numerical and Experimental Modeling of Natural Convection for a Cryogenic Prototype of a Titan Montgolfiere
نویسندگان
چکیده
Natural convection in a spherical geometry is considered for prediction of the buoyancy characteristics of one meter diameter singleand double-walled balloons in a cryogenic environment. The steady-state flow characteristics obtained by solving the ReynoldsAveraged Navier Stokes equations (RANS) with a standard k-ε model are used to determine the balloon performance in terms of net buoyancy as a function of heat input. Thermal radiation effects on the overall balloon performance are also investigated. The results obtained compared favorably with the corresponding cryogenic experiments conducted at the same scale in a cryogenic facility. In addition, both numerical and experimental results were compared with engineering heat transfer correlations used in system-level models of the Titan Montgolfiere. Finally, we examine scaling issues for the full-scale Titan Montgolfieres.
منابع مشابه
Computational Modeling and Experiments of Natural Convection for a Titan Montgolfiere
Computational models are developed to predict the natural convection heat transfer and buoyancy for a Montgolfiere under conditions relevant to the Titan atmosphere. Idealized single and double-walled balloon geometries are simulated using algorithms suitable for both laminar and (averaged) turbulent convection. Steady-state performance results are compared to existing heat transfer coefficient...
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