A	heat transfer surface area, m2
A m	heat transfer surface area of the mill chamber, m2
c	bead loading or fractional volumetric concentration of the beads, –
C p	specific heat capacity, J/g °C
EBM	enthalpy balance model
D b	bead size, µm
LPM	lumped-parameter model
m	mass in the mill chamber, g
ML	machine learning
PL	power law
P	power consumption, J/min
Pξ	heat generation rate during milling, retrieved from EBM study, J/min
Q gen	apparent heat generation during milling, J/min
RMSE	root-mean-squared error, °C
T	temperature at the mill outlet, °C
T ch	chiller temperature, °C
T rise	temperature rise at 6 min of milling, °C
T 0	initial temperature at the mill outlet, °C
t	milling time, min
U	overall heat transfer coefficient, W/m2 °C
UA	apparent overall heat transfer coefficient times surface area, J/min °C
UA m	apparent overall heat transfer coefficient times surface area in the mill chamber, J/min °C
ξ	fraction of mechanical power converted into heat, –
ω	stirrer (rotational) speed, rpm