  The 2015 Outburst of V404 Cygni is an unusual one with several X-ray and
radio flares and rapid variation in the spectral and timing properties. The
outburst occurred after $26$ years of inactivity of the black hole. We study
the accretion flow properties of the source during its initial phase of the
outburst using {\it Swift}/XRT and {\it Swift}/BAT data in the energy range of
$0.5-150$ keV. We have done spectral analysis with the two-component advective
flow (TCAF) model fits file. Several flow parameters such as two types of
accretion rates (Keplerian disk and sub-Keplerian halo), shock parameters
(location and compression ratio) are extracted to understand the accretion flow
dynamics. We calculated equipartition magnetic field $B$ for the outburst and
found that the highest $B \sim 900$~Gauss. Power density spectra (PDS) showed
no break, which indicates no or very less contribution of the Keplerian disk
component, which is also seen from the result of the spectral analysis. No
signature of prominent quasi-periodic oscillations (QPOs) is observed in the
PDS. This is due to the mismatch of the cooling timescale and infall timescale
of the post-shock matter.

High Energy Astrophysical Phenomena