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The local heat transfer enhancement in a parallel duct by local
blowing or suction slot at the heated wall has been numerically
studied on adaptive grid system, which is found from new grid
and adaptive grid generation methods. The flow solver employed
two-dimensional k-.epsilon. turbulent model, wall function
approximation on a generalized nonstaggered grid system and the
SIMPLE algorithm equipped by the QUICK scheme for convective
fluxes. The Sorenson and Steger elliptical grid generation
method is improved to have the function of grid control along
all of the boundaries. The improvement is achieved by
interpolating interior control functions from those found at
boundaries through transfinite interpolation, and two new
elliptic grid generation methods are subsequently developed.
Three new elliptic adaptive grid generation methods are also
developed based on the interpretation of control functions and
Anderson''s adaptive grid method. Among adaptive grid methods,
the most promising one combines present elliptic grid
generation, Anderson adaptive grid methods, and a new method
retaining background grid clustering and stretching. Numerical
test cases have illustrated the feasibility of all the grid
generation and adaptive grid methods. In studying the local
heat transfer enhancement, arrangements introducing a stream of
injecting fluid or sucking fluid through a slot at wall are
employed. Cases of uniform temperature and uniform heat flux at
heated wall, where the opposite wall is adiabatic, are
examined. It is found that both arrangements can enhance the
local heat transfer coefficient at the downstream side of the
slot. The considered situations are described by parameters of
the momentum flux ratio between injected (or and main stream,
slot angle measured from the upstream wall,
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