Predicting cleaning of equipment using computational fluid dynamics

In the food industry, production lines are ideally run for very long time periods without the need for cleaning. A prerequisite is that the equipment and the line are hygienically designed. This means that there are no stagnant areas, crevices or other parts of the flow domain that may cause entrapment of the product that can subsequently lead to bacterial growth. However, unhygienic geometries such as those described are frequently encountered in practice, and more frequent cleaning is a necessity. This article reported modeling results validated with experimental work. Computational fluid dynamics was used to assess the cleanability of a T-junction. Electrical conductivity measurements of a salt solution of known concentration before and after the T-junction is cleaned using deionized water were reported. This comparison gives an acceptable qualitative agreement with finite volume-based calculations that involve both steady-state and transient operations. This approach is a necessary prerequisite for the development of models that will ultimately include bacterial growth and deactivation kinetics under processing conditions.