Fluid dynamics simulations show that switching pumps on and off can reduce turbulence in pipes and reduce energy costs.
A joint study by the Okinawa Institute of Science and Technology Graduate University (OIST) and the Politecnico di Milano University found that transportation costs are significantly reduced when liquids are pumped through pipes intermittently.
In a proof-of-concept study recently published in Scientific Reports, researchers used numerical simulations to show that fluid flow transitions between turbulent and laminar states when the pump is periodically switched on and off. indicated to continue. This has reduced energy costs by up to 22%. This number, researchers say, could be further optimized.
Laminar flow, like the one you see when you slowly open a faucet, is smooth, streamlined, and energy efficient. On the other hand, turbulence, such as when the tap is fully open, is chaotic and wastes energy.
“When you inject ink in laminar flow, you see well-defined lines of ink moving down the pipe, but in turbulent flow, each fluid particle takes an unpredictable path, causing the ink to spread. This small Chaotic motion at scale results in a lot of energy loss,” explains Giulio Foggi Rota, lead author and current PhD student in the Complex Fluids and Flows Unit. “Laminar flow is ideal for fluid transport, but when a viscous fluid moves at high speed and large scale, the system naturally evolves into a turbulent state.”
Reducing turbulence and reducing the cost of moving fluids through pipes can have many economic and environmental benefits. Transportation of the fluid is a significant part of the final cost of the fuel, so if developed countries transition to liquid hydrogen, liquid hydrogen is likely to be cheaper. For developing countries that have not yet been able to switch to green energy, oil and natural gas could become a more affordable alternative to firewood.
In this study, researchers wrote code that, when run on a powerful supercomputer, could simulate standardized turbulence.
Scientists ran different scenarios by varying the time the pump was switched on, the intensity of the pump (how fast it accelerates the fluid), and the total amount of time each pump on/off cycle.
They found a long cycle featuring a short, powerful pump that rapidly accelerates the fluid flow, and a long phase that turns off the pump and slows down the fluid, perfect for keeping the fluid in a laminar flow-like state. I discovered that Maximum time.
As a next step, researchers are trying to better understand the physics underlying the repeated transitions between turbulent and layered states.
Professor Marco Edoardo Rosti said, “If we can more fully understand why fluids behave the way they do due to unsteady pumping, we can get a lot closer to figuring out the optimal pumping strategy for maximal energy savings. ‘ said. , OIST Heads the Complex Fluids and Flows Unit.
Original: New pumping strategy could reduce energy costs for fluid transport by 22%
Than: Okinawa Institute of Science and Technology Graduate University | Okinawa Institute of Science and Technology Graduate University Milan Polytechnic University
