PREP0002822 PCM Reference Material Developer

PCM Reference Material Development Researcher

Project Description:

Commercial phase change materials (PCMs) in the US and EU markets are incorporated in macro- and micro-encapsulations for latent heat storage in building energy applications. The thermal conductivity and the specific heat capacity of these PCM products, which are usually reported in the specification’s datasheet and are measured by a Heat Flow Meter (HFM), are the main thermal data used for installation guidance and energy saving calculations. However, these measurements exhibit non-linear behaviors with temperature due to contributions from the encapsulation materials and other factors. Therefore, the thermal behavior of encapsulated PCMs masks the thermal properties of the actual PCM and its phase change properties. Furthermore, the measurement by an HFM is fundamentally a relative measurement, being heavily correlated with the calibration of internal heat flux transducers using a reference material. This work aims to establish the groundwork needed to develop a reference material for validating the specific heat capacity values, as well as the thermal conductivity of macro-encapsulated PCMs. The research focus is to ultimately provide a new measurement service by developing a PCM reference material with reliable thermal properties and a well-defined phase-temperature relationship.

Key Responsibilities: 

• Simulate thermal distributions on empty and PCM-filled encapsulation panels between heating and cooling sources
• Determine thermal conductivity and heat capacity values of the PCM encapsulation panels using computational methods   
• Analyze the PCM melting and solidification process in the encapsulations using computational methods
• Present results at internal meetings and occasional meetings with external stakeholders
• Ensure that results, protocols, software, and documentation have been archived

Desired Qualifications: 

• Master’s degree in computer science, Engineering, Manufacturing, or a related field
• A minimum of 2 years of relevant experience is preferred 
• Familiarity with PCM and thermal simulations is a big plus
• Ability to work with a commercial finite element software (experience with COMSOL is preferred but not required)
• Ability to develop an analytical model needed to analyze data
• Strong oral and written communication skills

Other Details:

• Full-time: the participant is expected to work 40 hours a week
• Location: the participant will work at the NIST Gaithersburg Campus.
• Duration: this is expected to be a one-year position. Extensions are sometimes granted depending on the availability of funds.