The steam-assisted gravity drainage process (SAGD) is a promising meth
od for the in situ recovery of bitumen and heavy oil. A horizontal wel
l is employed as the producer because its extended contact with the re
servoir makes it possible to achieve economic production rates. Either
horizontal or vertical injection wells can be used. It is possible to
place the injection and the production wells wide apart vertically if
the viscosity of the in situ oil is a few thousand cp, e.g., in Lloyd
minister type reservoirs, whereas in bitumen reservoirs, a much closer
separation is usually employed. A major incentive in the use of verti
cal injection wells is that they may already be available from previou
s production. The major disadvantage of using vertical wells is that t
he steam chamber has to grow in the direction of the axis of the horiz
ontal well as well as transversely. Thus the effective length of the p
roduction well is less than its physical length at least until the ope
ration becomes mature. The present work focuses on the growth of the s
team chamber along the production well under different operating condi
tions and with varying configurations of injection and production well
s. Experiments were carried out using a three dimensional, scaled, cyl
indrical, physical model with central vertical injection wells. The ef
fect of parameters such as the type of production surface, thermal con
ductivity of production well, point of injection along the vertical in
jection well, and the effect of the injection of non-condensible gas a
long with steam were studied. A theoretical model to predict the growt
h of the steam chamber around the Vertical injection well is presented
. Predictions from this model are compared to field and experimental d
ata.