Quasi-2D Modeling of High-Aspect-Ratio-Cooling-Channel Flows

Abstract

A trade-off analysis is performed on a cooling channel system representative of liquid rocket engine cooling systems. This analysis requires multiple cooling channel flow calculations which are performed by means of a proper numerical approach, referred to as quasi-2D model. This model, which is suited to high-aspect-ratio cooling channels, permits to have a fast prediction of both the coolant flow evolution and the temperature distribution along the whole cooling channel structure. Before using the quasi-2D model for the trade-off analysis, its validation by comparison with CFD results is presented and discussed. Results show that the pump power required to overcome losses in the cooling circuit can be minimized selecting a channel shaped with a suitably high aspect ratio. Nomenclaturė m mass flow rate, kg s −1 A area of the channel cross section, m 2 b channel width, m D h channel hydraulic diameter, m f w skin friction factor G mass flow rate per unit area, kg m −2 s −1 h channel height, m h w heat transfer coefficient, W m −2 K −1 k thermal conductivity, W m −1 K −1 L channel length, m N number of cooling channels N u Nusselt number P channel perimeter, m p pressure, Pa P r Prandtl number q heat flux, W m −2 r chamber radius, m Re Reynolds number s w internal wall thickness, m T temperature, K t w rib thickness, m x, y, z length, height, and width coordinates, m Subscripts 0 total value aw adiabatic wall