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Hundreds of INUTEQ cooling vests developed for use by Dutch athletes at the Tokyo Olympics this summer have been donated for use in Dutch hospitals during the COVID-19 pandemic.
The PCM-equipped pullovers, designed to help athletes cope with heat stress, became available when the Tokyo Games were postponed until 2021. The pullovers can be worn under the heavy, heat-trapping protective gear used by doctors and nurses.
The pullovers are manufactured in Netherlands. The cooling material is Croda‘s CrodaTherm 21, a biobased PCM with a melting temperature of 21 degrees C. The 1.3-kg pullover is a simple “one-size-fits-most” garment, with two adjustable buckles and no fabric shell.
“Doctors and nurses at the ICU, who are treating corona patients, can work comfortably for up to three hours longer thanks to this cooling vest,” said Dr. Thijs Eijsvogels, physiologist at Radboud University Medical Center, Nijmegen. “The cooling vests ensure a stable body temperature, less sweating, maintenance of concentration and a faster recovery after each intensive work session.”
The pullover is marketed as “PCM CoolOver” on the INUTEQ website. It can be worn “under military combat gear, hazardous materials suits, mascot costumes and other professional apparel.”
Phase Energy Ltd. has announced the development of shape-stable technology for organic wax-based PCMs.
The company, based in Hull, United Kingdom, said a tetradecane-based shape-stable material would typically contain more than 90% PCM; the new technology has achieved levels of up to 96%. “Initial tests indicate that little, if any, enthalpy is lost, possibly due to the very low level of additives required,” the company said.
The technology was jointly developed with Rainer Busch of IBC Europe, Germany.
“So far, the technology has been used for paraffins, esters etc. and on a range of PCMs with [melt points] of up to 53 degrees Centigrade,” Phase Energy said in a LinkedIn post. “The technology permits the production of leak-resistant packs/pouches using very simple process technology.”
“We’re currently working with some companies in the cold chain area; looking at cold packs/pouches, pallet covers etc.,” Ian Biggin, director at Phase Energy, said in an e-mail. “As the technology can be adapted to higher temperature PCMs we are also interested in those areas as well but we decided that cold chain was the obvious place to start.”
U.S. patent application 20200131363 (applicant Rogers Corp., Chandler, Ariz.):
“A method of manufacturing a polyurethane phase-change composition comprises forming a curable composition comprising a homogeneous mixture of an organic isocyanate, a polyol having a hydroxyl functionality of 1.5 to 5, and a phase-change material; and curing the curable composition to obtain a polyurethane phase-change composition, wherein the polyurethane phase-change composition has a transition temperature, determined by differential scanning calorimetry according to ASTM D3418, of 5 to 70° C.”
U.S. patent application 20200136209 (applicant Toyota Motor Engineering & Manufacturing North America Inc., Plano, Texas):
“A battery module including a battery cell and a thermal management system for removing heat from the battery cell. The thermal management system includes two or more unit cells in an array. Each unit cell includes a primary shell comprising a primary phase change material (PCM), and a secondary shell comprising a secondary PCM that is thermally coupled to the primary shell. The battery cell is thermally coupled to the primary shell at a heat transfer interface and the secondary shells of adjacent unit cells in the array are separate.”
U.S. patent application 20200132897 (applicant TruIris LLC, Columbus, Ohio):
“Wearable ocular devices (such as ocular prostheses or contact lenses) utilizing diffraction gratings to produce color, as well as methods for producing such devices, are provided. A diffraction grating on the device may diffract the incident light to the observer. The result may be colored light that appears to originate from the wearer’s eyes. The diffraction grating may achieve a look or feeling that is qualitatively or quantitatively different from the look or feeling achieved by previous devices that use dyes or inks.”More U.S. patent applications:
Temperature management bedding systems | Graphene oxide aerogel beads | Thermal material with high capacity and high conductivity | Self-healing metal structures | Heat exchanger for three fluids | Steam power plant | Lightweight thermal battery
• The University of Twente, Netherlands, has an opening for a four-year Ph.D. position in phase change materials for heat storage. “This research project will try to introduce a smart composite material which can store the heat for both short and long-term storage time,” according to the posting. “This smart material will be based on inorganic salt hydrates having controllable discharging speed which is very advantageous for future smart heat batteries.” The starting salary is 2,325 euros per month, plus an annual 8.3% year-end bonus.
• Because of uncertainties associated with the COVID-19 pandemic, the 2020 Advancements in Thermal Management conference, scheduled for Aug. 6-7 in Denver, will be held as a virtual event on the same dates. According to the conference website: “Thermal 2020 presentations will be webcast with live slide presentations, audio, and real-time Q&A. Attendees may revisit these presentations after the event via recordings delivered directly to them. Exhibit booths feature rich, virtual profiles. Networking is done all-day via video conference rooms and though scheduled 1×1 meetings.” A full conference pass costs $295 through June 12.
• Peli BioThermal says air ambulance crews in Europe are transporting blood products via the company’s Credo ProMed transport bags. The temperature-controlled bags are designed to protect blood products needed for transfusions at emergency scenes.
• Researchers at the U.S. Department of Energy’s Argonne National Laboratory are working to integrate a new thermal energy storage technology within CHP systems from Capstone Turbine Corp. to boost heat recovery. In the Argonne system, high-temperature PCMs are embedded within highly thermally conductive foam. The foam is then sealed with inert gas inside a module, preventing moisture or oxygen from getting inside and degrading the components.
For our full list of recent academic research, see puretemp.com/academic. Here are highlights from the past week:From European Polymer Journal:
• Extremely fast synthesis of polythioether based phase change materials (PCMs) for thermal energy storage
From Journal of Building Engineering:
• Thermal behavior analysis of hollow bricks filled with phase-change material (PCM)
• FEM Applied to Building Physics: Modeling Solar Radiation and Heat Transfer of PCM Enhanced Test Cells
From Iranian Polymer Journal:
• Encapsulation of phase change materials with alginate modified by nanostructured sodium carbonate and silicate
From Energy & Fuels:
• Aluminium ammonium sulfate dodecahydrate with multiple additives as composite phase change materials for thermal energy storage
From Materials Today: Proceedings:
• Evaluation and reduction of temperature stresses in concrete pavement by using phase changing material
• Optimization of Heat Energy Based on Phase Change Materials used in Solar Collector using Taguchi Method
• Experimental and Theoretical Investigations on Thermal Conductivity of the Paraffin Wax using CuO Nanoparticles
From Journal of Energy Storage:
• Novel synthesis of silica coated palmitic acid nanocapsules for thermal energy storage
• Recent progress in phase change materials storage containers: Geometries, design considerations and heat transfer improvement methods
• Effect of phase separation and supercooling on the storage capacity in a commercial latent heat thermal energy storage: Experimental cycling of a salt hydrate PCM
• Energy efficiency optimization of the waste heat recovery system with embedded phase change materials in greenhouses: A thermo-economic-environmental study
• Characterization of innovative mortars with direct incorporation of phase change materials
From Applied Thermal Engineering:
• A trade study of a phase change system in a stratospheric airship based on a triple gasbag concept
• Experimental evaluation of structural insulated panels outfitted with phase change materials
• Lattice Boltzmann simulation of melting heat transfer in a composite phase change material
• Parametric modeling and simulation of low temperature energy storage for cold-climate multi-family residences using a geothermal heat pump system with integrated phase change material storage tank
• Multi-level uncertainty optimisation on phase change materials integrated renewable systems with hybrid ventilations and active cooling
• A novel solar thermal system combining with active phase-change material heat storage wall (STS-APHSW): Dynamic model, validation and thermal performance
From Advances in Energy Research:
• Theoretical Modeling of Phase Change Material-Based Space Heating Using Solar Energy
From Chemical Engineering Journal:
• High latent heat and recyclable form-stable phase change materials prepared via a facile self-template method
From Composites Part B: Engineering:
• In situ one-step construction of monolithic silica aerogel-based composite phase change materials for thermal protection
From Solar Energy:
• Effects of external insulation component on thermal performance of a Trombe wall with phase change materials
From Journal of Architectural Engineering:
• Experimental and Numerical Thermal Properties Investigation of Cement-Based Materials Modified with PCM for Building Construction Use
From Energy Conversion and Management:
• Experimental and numerical study on the thermal performance of ventilated roof composed with multiple phase change material (VR-MPCM)
From Construction and Building Materials:
• Multi-scale analysis on thermal properties of cement-based materials containing micro-encapsulated phase change materials
From Applied Energy:
• D-mannitol@silica/graphene oxide nanoencapsulated phase change material with high phase change properties and thermal reliability
• Novel bio-based phase change materials with high enthalpy for thermal energy storage
From Materials Today Energy:
• A detailed review on heat transfer rate, supercooling, thermal stability and reliability of nanoparticle dispersed organic phase change material for low-temperature applications
From International Journal of Thermal Sciences:
• Experimental study and assessment of high-tech thermal energy storing radiant floor heating system with latent heat storage materials
From Advanced Powder Technology:
• Paraffin core-polymer shell micro-encapsulated phase change materials and expanded graphite particles as an enhanced energy storage medium in heat exchangers
More than 1,500 people have joined a LinkedIn group devoted to the discussion of phase change material and thermal energy storage. The Phase Change Matters group is an interactive complement to the award-winning blog and newsletter of the same name.
You are invited to join the group and connect with PCM and TES experts from around the world. This month we welcome Gurkan Arif Yalcinkaya, owner, TLC Data Center, Istanbul, Turkey; Milad Arzani, research assistant at Surface Nano Engineering and masters student in mechanical engineering at University of Tehran, Iran; Mark Braley, technical sales manager – sensors at Acal BFi, Oxford, United Kingdom; Razan Bader, teaching assistant, PV design engineer at Power Source Jordan for Renewable Energy Systems, Amman, Jordan; and Ingo Horger, business development manager at Outlast Technologies, Germany.