It is difficult and challenging to design high-performance fuel additives i
n an industrial-design setting where data are sparse and noisy, and fundame
ntal knowledge is often limited. An automated framework is presented for th
e design of such fuel-additive molecules that minimize the intake-valve dep
osit in the automobile. A hybrid model that combined functional descriptors
from a first-principles degradation model with a statistical/neural-networ
k model was developed to predict additive performance, given the additive s
tructure. The results of the predictive model are discussed for differentia
l industrial case studies. An evolutionary method using specialized represe
ntation and constrained operators to enforce formulation constraints was us
ed to generate optimal additive molecules that meet desired performance cri
teria. The evolutionary design strategy in combination with the hybrid pred
iction model was successful in identifying novel additive molecules that al
so possess good synthesis potential.