Turner Jennings

Objective and outcomes

The objective of this design was to create a saline "bath" to submerge samples of murine blood vessels in during mechanical testing, capable of heating the saline to murine body temperature for biaxial pressure-extension mechanical tests with a duration of multiple hours. The bath was incorporated into an existing biaxial mechanical testing apparatus (pictured above). The system is currently used by Prof. Chiara Bellini and her lab members in the mechanical characterization of murine cardiovascular tissues.

This project highlights my ability to interface with existing designs to enhance capabilities and iterate on feedback from equipment operators.

System requirements

• The heating setup needed to fit within the size and mounting constraints of the existing test setup
• Due to temperature sensitivity and controlled concentrations of agents added to the saline, there could be no hot spots on the heating surface nor fluid mixing.
• The heating system needed to have an optically clear window to facilitate optical sample measurement

Heating channel cross-section

Key features

• Heating channels were designed into the main system body that connected to an external reservoir by a set of fluid manifolds. Temperature in the reservoir was controlled by a sous vide cooker to create a consistent heat flux into the sample bath via a hot water flow through the body.
• The fluid resistance in each channel was optimized such that the majority of the heat flux came through the bottom of the bath, supporting even temperature distribution through natural convection.
• The system was designed for easy dissassembly and cleaning to prevent contamination