  We study the recent outburst of the black hole candidate EXO 1846-031 which
went into an outburst in 2019 after almost 34 years in quiescence. We use
archival data from Swift/XRT, MAXI/GSC, NICER/XTI and NuSTAR/FPM
satellites/instruments to study the evolution of the spectral and temporal
properties of the source during the outburst. Low energy (2-10 keV) X-ray flux
of the outburst shows multiple peaks making it a multipeak outburst. Evolving
type-C quasi-periodic oscillations (QPOs) are observed in the NICER data in the
hard, hard intermediate and soft intermediate states. We use the physical Two
Component Advective Flow (TCAF) model to analyze the combined spectra of
multiple satellite instruments. According to the TCAF model, the accreting
matter is divided into Keplerian and sub-Keplerian parts, and the variation in
the observed spectra in different spectral states arises out of the variable
contributions of these two types of accreting matter in the total accretion
rate. Studying the evolution of the accretion rates and other properties of the
accretion flow obtained from the spectral analysis, we show how the multiple
peaks in the outburst flux arises out of variable supply of accreting matter
from the pile-up radius. We determine the probable mass of the black hole to be
$10.4^{+0.1}_{-0.2}~M_\odot$ from the spectral analysis with the TCAF model. We
also estimate viscous time scale of the source in this outburst to be $\sim 8$
days from the peak difference of the Keplerian and sub-Keplerian mass accretion
rates.
