Process engineering is the branch of chemical engineering that addresses the design, synthesis and operation of chemical or manufacturing processes in which raw materials are converted into products. Chemical engineers develop new processes or modify existing ones in order to optimize facilities; reduce costs or maximize profit; improve operations with respect to flexibility, reliability, energy efficiency and safety; and ensure quality control and address environmental impact. These goals are achieved by modeling and systematically analyzing industrial processes. Process engineering research at Princeton includes projects to design new power plants; computational approaches using novel mixed-integer nonlinear optimization and deterministic global optimization frameworks where discrete and continuous decisions are modeled explicitly for process design, synthesis, scheduling and planning applications; and efforts to develop a fundamental understanding of the time-dependent behavior of phenomena such as instabilities and oscillations in the dynamics of chemical reactors, as well as transitions to turbulence and pattern formation in fluid flow.