  We conduct 3D magnetohydrodynamic (MHD) simulations of decaying turbulence in
the solar wind context. To account for the spherical expansion of the solar
wind, we implement the expanding box model. The initial turbulence comprises
uncorrelated counter-propagating Alfv\'en waves and exhibits an isotropic power
spectrum. Our findings reveal the consistent generation of negative residual
energy whenever nonlinear interactions are present, independent of the
normalized cross helicity $\sigma_c$. The spherical expansion facilitates this
process. The resulting residual energy is primarily distributed in the
perpendicular direction, with $[S_2(\mathbf{b})-S_2(\mathbf{u})] \propto
l_\perp$ or equivalently $-E_r \propto k_\perp^{-2}$. Here $S_2(\mathbf{b})$
and $S_2(\mathbf{u})$ are second-order structure functions of magnetic field
and velocity respectively. In most runs, $S_2(\mathbf{b})$ develops a scaling
relation $S_2(\mathbf{b}) \propto l_\perp^{1/2}$ ($E_b \propto
k_\perp^{-3/2}$). In contrast, $S_2(\mathbf{u})$ is consistently shallower than
$S_2(\mathbf{b})$, which aligns with in-situ observations of the solar wind. We
observe that the higher-order statistics of the turbulence, which act as a
proxy for intermittency, are strongly affected by the expansion effect but have
weak dependence on the initial $\sigma_c$. Generally, the intermittency is more
pronounced when the expansion effect is present. Finally, we find that in our
simulations although the negative residual energy and intermittency grow
simultaneously as the turbulence evolves, there is no obvious causal relation
between them because they are generated on different scales.
