3D printing can be performed in countless ways; in fact, the choices are as infinite as the ability to innovate using this technology with an expanding force of hardware, software, and materials. Many different types of objects can be made that were not previously possible also, along with allowing for self-sustainability in creating items in the lab that can further a variety of studies. This was the case during a recent examination of thermal-physical properties by Italian researchers, explained in their recently published paper, ‘Coffee-based colloids for direct solar absorption.’
The researchers used 3D printing to create ‘collectors’ for their experiments for solar absorption, seeking an alternative to the usual carbon-based nanocolloids. To avoid the disadvantages of carbon—including cytotoxicity and harm to the environment—the authors leaned toward a much more natural mixture of:
- Arabica coffee
- Distilled water
- Copper sulphate
The study revolved around the creation of a better surface absorber overall, functioning via sunlight and its energy being passed to a carrier fluid. That carrier must possess suitable thermal and optical properties, however. Because coffee is so dark, it is more conducive to soaking up sunlight, and resulting heat—harkening back to previous studies with black India ink. That research was encouraging, and in considering it, the authors have combined their experiments to try and include nanocolloids—but without the toxicity.
“Different nanoparticle types have been investigated, such as single- and multi-walled nanotubes, graphite, nano-horns, or carbon powder in water. However, the increasing use of carbon nanoparticles may lead to major environmental concerns and biological risks, because of their (cyto)toxicity. In this sense, biocompatible (nano)colloids may represent a more sustainable and safe-by-design alternative to carbon-based nanosuspensions,” stated the researchers.
Coffee is much more complex than you may imagine (which may be the secret to the magic it bestows upon so many of us each morning), and available in a wide range of different compositions. For this experiment, the researchers used a stovetop aluminum coffee maker, with 100 cm3 maximum capacity, a 35 cm3 capacity filter, and a topper pot. Proposed colloids were then explored regarding extinction coefficient and stored energy fraction, while photo-thermal performance was compared with a selective surface absorber using the customized, 3D printed solar collectors. Three different flow rates were examined during the experiment.
“Experimental tests are carried out in the same conditions for direct and indirect absorption, and the efficiency of the collectors compared,” stated the researchers in their paper.
Regarding the performance of the 3D printed collectors, the researchers explained that a balance between absorption and reflection at the bottom of the channel was critical. Thermal conductivity was promoted via ‘tuning’ of the geometry channel.
“Field tests, in good agreement with numerical models, have demonstrated that these fluids can provide similar performance to the traditional indirect absorption based on selective surfaces,” concluded the researchers.
“These results may pave the way to a new, unconventional family of biocompatible, environmentally sustainable and inexpensive colloids for solar applications, for example suited for vapor formation, seawater desalination, domestic hot water production, or sustainable solar cooling.
As further advances are made in technology today, the options for materials in 3D printing continue to grow; however, this is not without concern for what types of energy we are using, along with how we are impacting the environment. Studies regarding materials and emissions, toxicity, and various methods for recycling continue to emerge also, along with different ways to harness solar energy in the actual exercise of 3D printing. Find out more about colloids and solar absorption here. What do you think of this news? Let us know your thoughts! Join the discussion of this and other 3D printing topics at 3DPrintBoard.com.[Source / Images: Coffee-based colloids for direct solar absorption]
You May Also Like
3D Printing Webinar and Virtual Event Roundup, September 27, 2020
A range of topics will be covered in this week’s roundup of webinars and virtual events, starting with controlled nesting and increased productivity. Moving on, attendees can learn how to...
What Does the Siemens-Nexa3D Partnership Mean for 3D Printing?
3D printer manufacturer Nexa3D has announced a collaboration with technology company Siemens to automate its polymer laser sintering systems. Even during COVID-19, the two companies have remained committed to Industry...
3D Printing News Briefs, August 11, 2020: 3DEO, Nexa3D, AK Medical
In today’s 3D Printing News Briefs, 3DEO has won a design competition, and Nexa3D will be demonstrating its expanded line of ultra-fast polymers at this week’s AM Industry Summit. Finally,...
3D Printing Webinar and Virtual Event Roundup, August 9, 2020
We’ve only got four online events to tell you about this week—a summit and a few webinars, one of which is on-demand. Read on to learn more! AM Industry Virtual...
View our broad assortment of in house and third party products.