  Dust attenuation in star-forming galaxies (SFGs), as parameterized by the
infrared excess (IRX $\equiv L_{\rm IR}/L_{\rm UV}$), is found to be tightly
correlated with star formation rate (SFR), metallicity and galaxy size,
following a universal IRX relation up to $z=3$. This scaling relation can
provide a fundamental constraint for theoretical models to reconcile galaxy
star formation, chemical enrichment, and structural evolution across cosmic
time. We attempt to reproduce the universal IRX relation over $0.1\leq z\leq
2.5$ using the EAGLE hydrodynamical simulations and examine sensitive
parameters in determining galaxy dust attenuation. Our findings show that while
the predicted universal IRX relation from EAGLE approximately aligns with
observations at $z\leq 0.5$, noticeable disparities arise at different stellar
masses and higher redshifts. Specifically, we investigate how modifying various
galaxy parameters can affect the predicted universal IRX relation in comparison
to the observed data. We demonstrate that the simulated gas-phase metallicity
is the critical quantity for the shape of the predicted universal IRX relation.
We find that the influence of the infrared luminosity and infrared excess is
less important while galaxy size has virtually no significant effect. Overall,
the EAGLE simulations are not able to replicate some of the observed
characteristics between IRX and galaxy parameters of SFGs, emphasizing the need
for further investigation and testing for our current state-of-the-art
theoretical models.
