Micro- and millistructured reactors offer significant advantages compared to conventional reactors, e.g., in terms of heat and mass transfer as well as safety. For the substitution of larger batch reactors by continuously operated millireactors a comprehensive reactor characterization is required. The heat transfer and hydrodynamics of the millistructured plate reactor PR37 are studied. The meandering of the process channel and its periodically changing cross-sectional area increase the heat transfer significantly and lead to a dependency of the heat transfer coefficient on the Reynolds and Prandtl number that is not found in straight channels at Reynolds numbers below 2300.
