Dry ice sublimation: A computational study with experimental validation for the effects of geometry

Area of Science:

• Physical Sciences
• Chemical Engineering
• Thermodynamics

Background:

• Dry ice is crucial for cold-chain distribution of temperature-sensitive products.
• Current sublimation estimates (3%-8% per day) are general and do not account for geometry.
• Mass is the primary specification, overlooking geometric influences on sublimation rates.

Purpose of the Study:

• To develop and validate a computational model for dry ice sublimation.
• To investigate the impact of geometry and orientation on dry ice sublimation rates.
• To enhance understanding of dry ice cooling for practical cold-chain applications.

Main Methods:

• Experimental sublimation of dry ice blocks.
• Development and validation of a multi-physics computational model.
• Inclusion of radiation and convection heat transfer, and computational fluid dynamics.
• Evaluation of geometric feature changes during sublimation.

Main Results:

• The volume-to-surface area ratio is a key parameter for sublimation cooling performance.
• For identical masses, spherical dry ice (high volume-to-surface area ratio) sublimates nearly 50% slower than block-shaped dry ice (lower ratio).
• Model validation confirmed the significant influence of geometry on sublimation.

Conclusions:

• Dry ice geometry critically affects sublimation rates and cooling efficiency.
• Optimizing dry ice shape can significantly improve cold-chain management.
• The validated model provides a tool for predicting and managing dry ice sublimation.