Lesson #9: Comparison of Rigid and Flexible gel packs
Gel Packs are a critical component of a thermal system, in most cases more important than insulation, since they provides a source of energy (and/or heat sink) which allows maintenance of temperature within an insulated container.
Gel Packs can be segragated in two main categories: rigid (or bricks) and flexible bags. These categories describe the type of packaging that is used to contain the phase change material (PCM) contained within them.
Rigid/Brick Gel Packs: they usually come in the form of ‘bricks’ or bottles. These gel packs are ideal for use when rigidity or reusability are required while also providing a more reliable shape when frozen when compared to flexible film gel packs.
Custom sizes are typically expensive to manufacture and can require long lead times because tooling requirements.
The following are examples of typical rigid Gel Packs:
Flexible Gel Packs: they are the lowest cost type of gel packs. With the low cost typically comes the inability to re-use them and the higher potential for leakage. These requires that the Phase Change Material (PCM) typically be in the form of a gel, which is usually water based.
Custom sizes are typically readily manufactured since tooling is not required.
The following are examples of typical flexible Gel Packs: