The surface of the wavy wall and the convex pyramid structure designed thanks to the 3D printing technology means that the power density of the heat exchanger exceeds 6 megawatts per cubic meter, and cooling efficiency is 30% to 50% higher than that of traditional design, providing new ideas for copying with double energy consumption of construction in 205. Simulations to see the optimal channel of the flow channel and the optimal flow and the layer of finesse. Although limited by the cost of laser sintering, this technology will be the first to shed light on the dawn of the cooling revolution in high -added fields such as aerospace.
As a key device for the transmission of thermal energy, heat exchangers have entered all corners of modern society, including data centers, ships, factories and various buildings.
The essential function of this type of equipment is to obtain an effective heat transfer, but at this stage, due to traditional manufacturing processes, consumer products currently use several standard structures with the lowest cost and the simplest treatment.
A new study shows that innovative structures designed thanks to 3D printing technology can make the main components of refrigeration equipment such as air -and more efficient air conditioners and refrigerators. Currently, research results have been published in the International Journal of Heat and Mass Transfer.
“Heat exchangers are one of the main devices of the industrial economy, and they are an important part of each machine and each energy transfer system,” notes William King, professor at the University of Illinois in Urbana-Champaign. “The existing conceptions generally use structures that are easy to use such as straight lines, right angles and round tubes.”
In response, he and his team used 3D printing technology to cross the limits of traditional and developed manufacturing innovative structures with corrugated walls and pyramid -type bulges. These conceptions can considerably optimize the thermal conduction path, which is difficult to achieve by traditional manufacturing techniques.
The research team has designed the system based on a common R-134A refrigerant, which is widely used in equipment such as air conditioners and refrigerators.
When cold water lowers the temperature of the refrigerant, it passes from gas to liquid during the process of passage through the device. This liquid refrigerant can then enter other parts of the cooling system to reduce the temperature of various parts of the part to the server grid.
The most effective way to refrigerate is generally by building very fine walls between the sides of the equipment and maximizing the contact area between water and the refrigerant and these walls. (Imagine being lying on ice in a thin t-shirt is certainly much colder than touching the ice with your hands with gloves.)
To design the best heat exchanger, researchers used simulation techniques and automatic learning models developed to predict the performance of different conceptions in a variety of conditions.
After 36,000 simulation checks, the researchers finally finalized the design. The main innovations, one is to add many small fins to the side of the equipment by contacting the water, which widens the surface to maximize heat transfer; The second is to design a wavy water flow path, which again helps to increase the contact zone. Thanks to the simulation, the researchers accurately calculated the degree of flexion of the canal and the optimal position of the fins.
On the side where the refrigerant circulates, small pyramid type protuberances distributed along the wall are added to the design. These structures increase not only the cooling area, but also promote the mixture as the refrigerant passes, preventing the liquid from adhering to the walls of the tube (this fixation will reduce the efficiency of the heat transfer).
After determining the final design, the researchers used a 3D printing technology called “Direct Laser Metal Straving”, which used the laser layer by layer to melt the metal powder (the experience used aluminum alloy powder) to finally build a complete heat exchanger equipment structure.
The test results show that heat exchangers manufactured by this technology cool the refrigerant more effectively than other conceptions. Under the same pumping power conditions, its power density exceeds 6 megawatts per cubic meter, which is 30% to 50% higher than the common shell and tube exchangers, and its power density is comparable to another common industrial design (such as heat exchangers with breastplates).
“Although this device does not significantly exceed the most advanced technologies at present, there are a lot of potential for the use of modeling and 3D printing to develop new conceptions of heat exchanges,” commented Dennis Nasuta, director of R&D at Optimize Thermal Systems, a consulting firm of the HVAC industry. “There is still room for exploration and we have not yet touched its performance ceiling.”
However, Dennis Nasuta also underlined the current bottleneck. Compared to traditional manufacturing, additive manufacturing technologies such as laser sintering still have low efficiency and high cost problems, and it is difficult to apply them large -scale to short -term civil refrigeration equipment. He thinks that this technology can be the first to implement in sub-sectors such as aerospace and high-end cars that can withstand high costs.
It is expected that the energy refrigeration energy consumption will double by 2050, and an innovative design is crucial to deal with a huge demand for energy in the future. “The increase in the number of electronic equipment transported by modern ships has done an urgent need for compact and effective cooling systems,” said Nenad Miljkovic, member of the research team.
However, many challenges, including manufacturing costs, still have to be overcome before innovations like William King and the designed team really work in real equipment.
Dennis Nasuta has also noted that another obstacle to the adoption of these new technologies is that current standards do not require higher efficiency. In fact, there is already a variety of technologies that can improve the efficiency of equipment on the market, but they have not been popularized for similar reasons.
“It will take a long process to really enter the houses of ordinary people,” he admitted, “therefore, this technology will not appear in home air conditioners next year.”
