Numerical studies are conducted on turbulent incompressible flow over 2D backwardfacing
step in order to investigate the performance of three different turbulence models (standard k-e,
realizable k-e and SST k-ω) in predicting the region of separation and reattachment behind the edge
of the step. Current solutions of Reynolds number (Re= 13200) and expansion ratio (H: H2=1:3) are
compared with experimental measurements. Among the turbulence models, SST k-ω and standard k-e exhibited good agreement with the experimental results.
In this paper, Reynolds average Navier stokes models simulation was computed
with standard k-є, realizable k-є and SST k-w.The three models were proposed to forecast the
turbulence flow behaviour inside a rectangular channel with two baffle plates. The geometry
and the grid were generated using commercial CFD software fluent. The flow behaviours of
three models were characterized based on positions of the entrance to the first baffle,
positions between first and second baffle and lastly the second baffle. At the three different
positions the three models studied have demonstrate differences in the velocity profiles and
separation range. Comparison with previous literatures shows applicability of these three
models to produce velocity profile characteristics and separation behaviours. Even though
some of the models have shown slight deviation from the experimental results but in general
the three models were considered to be in close agreement with most published literatures.
This paper studied the heat transfer in an asphalt solar collector with small scale geometry.
Solar energy reaches the earth and consequently increases the temperature of the ground, which then
leads to the increase of the temperature of the air. Water circulates through a series of pipes embedded
in the asphalt pavement for the extraction of solar energy. The radiation in this study was produced
from the top asphalt pavement. In this study, the temperature of the asphalt pavement decreased when
solar energy was collected from the circulating water. This reduces the heat island effect in the city and
decreases the power consumption for air conditioning. The temperature is distributed between the
asphalt pavement and the inner pipes. Increase of the flow rate has a great influence on the energy
collection by reducing the temperature of the asphalt pavement. The result of this test was obtained
using a small-scale asphalt pavement, which showed a high amount of heat collected.