  The effects of the heliospheric current sheet (HCS) on the evolution of
Alfv\'enic turbulence in the solar wind are studied using MHD simulations
incorporating the expanding-box-model (EBM). The simulations show that near the
HCS, the Alfv\'enicity of the turbulence decreases as manifested by lower
normalized cross helicity and larger excess of magnetic energy. The numerical
results are supported by a superposed-epoch analysis using OMNI data, which
shows that the normalized cross helicity decreases inside the plasma sheet
surrounding HCS, and the excess of magnetic energy is significantly enhanced at
the center of HCS. Our simulation results indicate that the decrease of
Alfv\'enicity around the HCS is due to the weakening of radial magnetic field
and the effects of the transverse gradient in the background magnetic field.
The magnetic energy excess in the turbulence may be a result of the loss of
Alfv\'enic correlation between velocity and magnetic field and the faster decay
of transverse kinetic energy with respect to magnetic energy in a spherically
expanding solar wind.
