Figure 9 shows that the heat transfer coefficient of the first effect is more important that that of the second effect, due to the layout of the triangle evaporator station, where there is an additional first effect vessel, which feeds the two evaporator additional first effect vessel, which feed the two evaporator trains equally. The responses of each of the first effect vessels were not identical.
The extra first effect, 1c , was found to have a slightly different relationship between its observed heat transfer coefficient and the optimal flow distribution.