  Resolving fluid transport at engine surfaces is required to predict transient
heat loss, which is becoming increasingly important for the development of
high-efficiency internal combustion engines (ICE). The limited number of
available investigations have focused on non-reacting flows near engine
surfaces, while this work focuses on the near-wall flow field dynamics in
response to a propagating flame front. Flow-field and flame distributions were
measured simultaneously at kHz repetition rates using particle tracking
velocimetry (PTV) and planar laser induced fluorescence (PLIF) of sulfur
dioxide (SO2). Measurements were performed near the piston surface of an
optically accessible engine operating at 800 rpm with homogeneous,
stoichiometric isooctane-air mixtures. High-speed measurements reveal a strong
interdependency between near-wall flow and flame development which also
influences subsequent combustion. A conditional analysis is performed to
analyze flame/flow dynamics at the piston surface for cycles with weak and
strong flow velocities parallel to the surface. Faster flame propagation
associated with higher velocities before ignition demonstrates a stronger flow
acceleration ahead of the flame. Flow acceleration associated with an advancing
flame front is a transient feature that strongly influences boundary layer
development. The distance from the wall to 75% maximum velocity ({\delta}75) is
analyzed to compare boundary layer development between fired and motored
datasets. Decreases in {\delta}75 are strongly related to flow acceleration
produced by an approaching flame front. Measurements reveal strong deviations
of the boundary layer flow between fired and motored datasets, emphasizing the
need to consider transient flow behavior when modelling boundary layer physics
for reacting flows.
