الفهرس 
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Abstract
The purpose of this work iS to provide the correlation between the
greenhouse, the flow separation, and now separation control. in particular in
internal flow. Understanding of some basic mechanism of greenhouse effects
has increased substantially in the iast few years. This undetstauding suggests
that taming of greenhouse - the new challenge in the field of flow separation
control ~ is possible so as to eliminate some of ib deleterious effecl<; while
enhancing its useful traits.
Under certain conditions of pressure and velocity gradients, wall-hounded
flows separate. To improve the performance of natural or man-made
flow systems, it moy beneficial to de)a.y or advance this detachment process.
A well designed and manufactured of two-dimensional flat-walled diffuser
is manipulated. The diffuser with specific dimensions has a separation
and backflow near the exit due to an adverse pressure gradient.
The experimental measurements were carried out at four stations to gain
information of pressure and velocity distributions of air flow through
the diffuser. The experimental procedure begins with normal air in order
to be used as a reference with the hot air with free exit and hot air with
boundary condition at the exit of the diffuser, greenhouse simulation. The
separation point is determined theoreticaUy using an integral approach of
empirical method. Flow separation control is currently employed, injection of
air directly in the boundary-layer regions, to show the effect of blowing on
flow separation and the performance of the diffuser. However, the pressure
recovery coefficient and the performance of the diffuser are found to be
function of the rate of injection.
The hot air with different temperatures through the diffuser is used
to investigate the effect of hot air on flow separation. However, the new
location of separation point is. expected due to the e!Tect of hot air and
compared with the ca..”ie of using normal air.
The greenhouse effect is attained in lhe experiment through using
a. cotton screen with specific porosity located near the exit of the diffuser. The
cotton screen as an impedance creates a pressure DROP across it that associates
an adverse pressure gradient in the boundary layer regions near the exit
of the diffuser. However, the location of the separation poinl and the
pressure recovery coefficient would be expected to be related with the
greenhouse effect. Therefore, the experimental measurements are necessary
and relevant to investigate the link between the greenhouse, the flow
separalion, and the flow separation controL