# Modular Design of Vacuum Systems for Lyophilization

## TL;DR

This paper introduces a method to design custom vacuum systems for lyophilization by combining CFD and analytical models.

## Contribution

A novel method for predicting vacuum performance by concatenating CFD and analytical models of individual components.

## Key findings

- A vacuum chamber validated the pressure prediction method successfully.
- A larger vacuum tunnel was designed and built, achieving a target pressure below 10 Pa.
- The method accurately predicted performance for custom geometry lyophilization systems.

## Abstract

Computational Fluid
Dynamics (CFD) can be used to characterize
lyophilization vacuum systems, but these simulations are typically
unique to a specific geometry. This work presents a general method
for predicting pressure performance by concatenating CFD and analytical
models of individual components to create a vacuum system model. This
method enables rapid exploration of vacuum system layouts to build
custom geometry lyophilizers, which is particularly useful for novel
continuous lyophilization systems. A vacuum chamber was built to validate
this pressure prediction method. The simulations were then used to
design a larger vacuum tunnel for continuous lyophilization that could
achieve a target pressure below 10 Pa throughout its length. This
tunnel was then built, and its performance matched the predictions
of the component concatenation method. These results indicate that
the component simulation and concatenation methods can be effectively
used to predict the vacuum performance of custom geometry lyophilization
systems.