Mean stratification 〈Q〉_τ (top row) and fluctuations 〈δQ〉_τ (middle row) of the radiative energy exchange rate averaged over surfaces of the constant Rosseland optical depth and time of the G2V (left column), K0V (middle), and M2V (right) stars. The black, blue, and red curves in the top and middle row corresponds to the results computed from the simulations run using the 18OB, 4OB, and grey opacity setups, respectively. The deviation measures χ_C and χ_H are shown in the legend at the panels of the top row. Bottom row: relative difference of 〈δQ〉_τ computed with 4OB (blue curve), and grey (red) compared to 〈δQ〉_τ obtained using 18OB. The fluctuations shown in the middle row are computed as the standard deviation of Q.