Supercomputing Propels Jet Atomization Research for Industrial Processes

February 8, 2019

Feb. 8, 2019 — Whether it is designing the most effective method for fuel injection in engines, building machinery to water acres of farmland, or painting a car, humans rely on liquid sprays for countless industrial processes that enable and enrich our daily lives.

To understand how to make liquid jet spray cleaner and more efficient, though, researchers have to focus on the little things: Scientists must observe fluids flowing in atomic, microsecond detail in order to begin to understand one of science’s great challenges—turbulent motion in fluids.

Visualization of the liquid surface and velocity magnitude of a round jet spray.
Copyright: Bundeswehr University Munich

Experiments serve as an important tool for understanding industrial spray processes, but researchers have increasingly come to rely on simulation for understanding and modelling the laws governing the chaotic, turbulent motions present when fluids are flowing quickly.

A team of researchers led by Prof. Dr. Markus Klein at the Bundeswehr University Munich (German: Universität der Bundeswehr München) understood that modelling the complexities of turbulence accurately and efficiently requires it to employ high-performance computing (HPC), and recently, it has been using Gauss Centre for Supercomputing (GCS) resources at the Leibniz Supercomputing Centre (LRZ) in Garching near Munich to create high-end flow simulations for better understanding turbulent fluid motion.

“Our goal is to develop simulation software that someone can apply commercially for real engineering problems,” says Dr. Josef Haßlberger, collaborator on the Klein team. He works together with collaborator Sebastian Ketterl on the computational project. The team’s research recently was chosen for the cover of the Journal of Fluid Mechanics.

It’s a (multi)phase

When scientists and engineers speak of liquid sprays, there is a bit more nuance to it than that—most sprays are actually multiphase phenomena, meaning that some combination of a liquid, solid, and gas are flowing at the same time. In sprays, this generally happens through atomization, or the breakup of a liquid fluid into droplets and ligaments, eventually forming vapours in some applications.

Researchers need to account for this multiphase mixing in their simulations with enough detail to understand some of the minute, fundamental processes governing turbulent motions—specifically, how droplets form, coalesce and break-up, or the surface tension dynamics between liquids and gases—while also capturing a large enough area to see how these motions impact jet sprays. Droplets are formed and influenced by turbulent motion, but also further influence turbulent motion after forming, creating the need for very detailed and accurate numerical simulation.

When modeling fluid flows, researchers have several different methods they can use. Among them, direct numerical simulations (DNS) offer the highest degree of accuracy, as they start with no physical approximations about how a fluid will flow and recreates the process “from scratch” numerically down to the smallest levels of turbulent motion (“Kolmogorov-scale” resolution). Due to its high computational demands, DNS simulations are only capable of running on the world’s most powerful supercomputers, such as SuperMUC at LRZ.

Another common approach for modeling fluid flows, large-eddy simulations (LES), make some assumptions about how fluids will flow at the smallest scales, and instead focus on simulating larger volumes of fluids over longer periods of time. For LES simulations to accurately model fluid flows, though, the assumptions built into the model must rely on quality input data for these small-scale assumptions, hence the need for DNS calculations.

To simulate turbulent flows, the researchers created a three-dimensional grid with more than a billion individual small cells, solving equations for all forces acting on this fluid volume, which according to Newton’s second law, give rise to a fluid accelerating. As a result, the fluids velocity can be simulated in both space and time. The difference between turbulent and laminar, or smooth, flows depends on how fast a fluid is moving as well as how thick, or viscous, it is and in addition to the size of the flow structures. Then researchers put the model in motion, calculating liquid properties from the moment it leaves a nozzle until it has broken up into droplets.

Based on the team’s DNS calculations, it began developing new models for fine-scale turbulence data that can be used to inform LES calculations, ultimately helping to bring accurate jet spray simulations to a more commercial level. LES calculates the energy carrying large structures, but the smallest scales of the flow are modelled, meaning that LES calculations potentially provide high accuracy for a much more modest computational effort.

Flowing in the right direction

Although the team has made progress in improving LES models through gaining a more fundamental understanding of fluid flows through its DNS simulations, there is still room for improvement. While the team can currently simulate the atomization process in detail, it would like to observe additional phenomena taking place on longer time scales, such as evaporation or combustion processes.

Next-generation HPC resources will help to close the gap between academic-caliber DNS of flow configurations and real experiments and industrial applications. This will give rise into more realistic databases for model development and will provide detailed physical insight into phenomena that are difficult to observe experimentally.

In addition, the team has more work to do to implement its improvements to LES models. The next challenge is to model droplets that are smaller than the actual grid size in a typical large-eddy simulation, but still can interact with the turbulent flow and can contribute to momentum exchange and evaporation.


Source: Eric Gedenk, Gauss Centre for Supercomputing

Subscribe to HPCwire's Weekly Update!

Be the most informed person in the room! Stay ahead of the tech trends with industy updates delivered to you every week!

Insights from Optimized Codes on Cineca’s Marconi

February 15, 2019

What can you do with 381,392 CPU cores? For Cineca, it means enabling computational scientists to expand a large part of the world’s body of knowledge from the nanoscale to the astronomic, from calculating quantum effe Read more…

By Ken Strandberg

What Will IBM’s AI Debater Learn from Its Loss?

February 14, 2019

The utility of IBM’s latest man-versus-machine gambit is debatable. At the very least its Project Debater got us thinking about the potential uses of artificial intelligence as a way of helping humans sift through al Read more…

By George Leopold

ClusterVision in Bankruptcy, Fate Uncertain

February 13, 2019

ClusterVision, European HPC specialists that have built and installed over 20 Top500-ranked systems in their nearly 17-year history, appear to be in the midst of bankruptcy proceedings. According to Dutch news site Drimb Read more…

By Tiffany Trader

HPE Extreme Performance Solutions

HPE Systems With Intel Omni-Path: Architected for Value and Accessible High-Performance Computing

Today’s high-performance computing (HPC) and artificial intelligence (AI) users value high performing clusters. And the higher the performance that their system can deliver, the better. Read more…

IBM Accelerated Insights

Medical Research Powered by Data

“We’re all the same, but we’re unique as well. In that uniqueness lies all of the answers….”

  • Mark Tykocinski, MD, Provost, Executive Vice President for Academic Affairs, Thomas Jefferson University

Getting the answers to what causes some people to develop diseases and not others is driving the groundbreaking medical research being conducted by the Computational Medicine Center at Thomas Jefferson University in Philadelphia. Read more…

South African Weather Service Doubles Compute and Triples Storage Capacity of Cray System

February 13, 2019

South Africa has made headlines in recent years for its commitment to HPC leadership in Africa – and now, Cray has announced another major South African HPC expansion. Cray has been awarded contracts with Eclipse Holdings Ltd. to upgrade the supercomputing system operated by the South African Weather Service (SAWS). Read more…

By Oliver Peckham

Insights from Optimized Codes on Cineca’s Marconi

February 15, 2019

What can you do with 381,392 CPU cores? For Cineca, it means enabling computational scientists to expand a large part of the world’s body of knowledge from th Read more…

By Ken Strandberg

ClusterVision in Bankruptcy, Fate Uncertain

February 13, 2019

ClusterVision, European HPC specialists that have built and installed over 20 Top500-ranked systems in their nearly 17-year history, appear to be in the midst o Read more…

By Tiffany Trader

UC Berkeley Paper Heralds Rise of Serverless Computing in the Cloud – Do You Agree?

February 13, 2019

Almost exactly ten years to the day from publishing of their widely-read, seminal paper on cloud computing, UC Berkeley researchers have issued another ambitious examination of cloud computing - Cloud Programming Simplified: A Berkeley View on Serverless Computing. The new work heralds the rise of ‘serverless computing’ as the next dominant phase of cloud computing. Read more…

By John Russell

Iowa ‘Grows Its Own’ to Fill the HPC Workforce Pipeline

February 13, 2019

The global workforce that supports advanced computing, scientific software and high-speed research networks is relatively small when you stop to consider the magnitude of the transformative discoveries it empowers. Technical conferences provide a forum where specialists convene to learn about the latest innovations and schedule face-time with colleagues from other institutions. Read more…

By Elizabeth Leake, STEM-Trek

Trump Signs Executive Order Launching U.S. AI Initiative

February 11, 2019

U.S. President Donald Trump issued an Executive Order (EO) today launching a U.S Artificial Intelligence Initiative. The new initiative - Maintaining American L Read more…

By John Russell

Celebrating Women in Science: Meet Four Women Leading the Way in HPC

February 11, 2019

One only needs to look around at virtually any CS/tech conference to realize that women are underrepresented, and that holds true of HPC. SC hosts over 13,000 H Read more…

By AJ Lauer

IBM Bets $2B Seeking 1000X AI Hardware Performance Boost

February 7, 2019

For now, AI systems are mostly machine learning-based and “narrow” – powerful as they are by today's standards, they're limited to performing a few, narro Read more…

By Doug Black

Assessing Government Shutdown’s Impact on HPC

February 6, 2019

After a 35-day federal government shutdown, the longest in U.S. history, government agencies are taking stock of the damage -- and girding for a potential secon Read more…

By Tiffany Trader

Quantum Computing Will Never Work

November 27, 2018

Amid the gush of money and enthusiastic predictions being thrown at quantum computing comes a proposed cold shower in the form of an essay by physicist Mikhail Read more…

By John Russell

Cray Unveils Shasta, Lands NERSC-9 Contract

October 30, 2018

Cray revealed today the details of its next-gen supercomputing architecture, Shasta, selected to be the next flagship system at NERSC. We've known of the code-name "Shasta" since the Argonne slice of the CORAL project was announced in 2015 and although the details of that plan have changed considerably, Cray didn't slow down its timeline for Shasta. Read more…

By Tiffany Trader

The Case Against ‘The Case Against Quantum Computing’

January 9, 2019

It’s not easy to be a physicist. Richard Feynman (basically the Jimi Hendrix of physicists) once said: “The first principle is that you must not fool yourse Read more…

By Ben Criger

AMD Sets Up for Epyc Epoch

November 16, 2018

It’s been a good two weeks, AMD’s Gary Silcott and Andy Parma told me on the last day of SC18 in Dallas at the restaurant where we met to discuss their show news and recent successes. Heck, it’s been a good year. Read more…

By Tiffany Trader

Intel Reportedly in $6B Bid for Mellanox

January 30, 2019

The latest rumors and reports around an acquisition of Mellanox focus on Intel, which has reportedly offered a $6 billion bid for the high performance interconn Read more…

By Doug Black

US Leads Supercomputing with #1, #2 Systems & Petascale Arm

November 12, 2018

The 31st Supercomputing Conference (SC) - commemorating 30 years since the first Supercomputing in 1988 - kicked off in Dallas yesterday, taking over the Kay Ba Read more…

By Tiffany Trader

Looking for Light Reading? NSF-backed ‘Comic Books’ Tackle Quantum Computing

January 28, 2019

Still baffled by quantum computing? How about turning to comic books (graphic novels for the well-read among you) for some clarity and a little humor on QC. The Read more…

By John Russell

Contract Signed for New Finnish Supercomputer

December 13, 2018

After the official contract signing yesterday, configuration details were made public for the new BullSequana system that the Finnish IT Center for Science (CSC Read more…

By Tiffany Trader

Leading Solution Providers

SC 18 Virtual Booth Video Tour

Advania @ SC18 AMD @ SC18
ASRock Rack @ SC18
DDN Storage @ SC18
HPE @ SC18
IBM @ SC18
Lenovo @ SC18 Mellanox Technologies @ SC18
NVIDIA @ SC18
One Stop Systems @ SC18
Oracle @ SC18 Panasas @ SC18
Supermicro @ SC18 SUSE @ SC18 TYAN @ SC18
Verne Global @ SC18

Deep500: ETH Researchers Introduce New Deep Learning Benchmark for HPC

February 5, 2019

ETH researchers have developed a new deep learning benchmarking environment – Deep500 – they say is “the first distributed and reproducible benchmarking s Read more…

By John Russell

ClusterVision in Bankruptcy, Fate Uncertain

February 13, 2019

ClusterVision, European HPC specialists that have built and installed over 20 Top500-ranked systems in their nearly 17-year history, appear to be in the midst o Read more…

By Tiffany Trader

IBM Quantum Update: Q System One Launch, New Collaborators, and QC Center Plans

January 10, 2019

IBM made three significant quantum computing announcements at CES this week. One was introduction of IBM Q System One; it’s really the integration of IBM’s Read more…

By John Russell

Nvidia’s Jensen Huang Delivers Vision for the New HPC

November 14, 2018

For nearly two hours on Monday at SC18, Jensen Huang, CEO of Nvidia, presented his expansive view of the future of HPC (and computing in general) as only he can do. Animated. Backstopped by a stream of data charts, product photos, and even a beautiful image of supernovae... Read more…

By John Russell

HPC Reflections and (Mostly Hopeful) Predictions

December 19, 2018

So much ‘spaghetti’ gets tossed on walls by the technology community (vendors and researchers) to see what sticks that it is often difficult to peer through Read more…

By John Russell

IBM Bets $2B Seeking 1000X AI Hardware Performance Boost

February 7, 2019

For now, AI systems are mostly machine learning-based and “narrow” – powerful as they are by today's standards, they're limited to performing a few, narro Read more…

By Doug Black

The Deep500 – Researchers Tackle an HPC Benchmark for Deep Learning

January 7, 2019

How do you know if an HPC system, particularly a larger-scale system, is well-suited for deep learning workloads? Today, that’s not an easy question to answer Read more…

By John Russell

Intel Confirms 48-Core Cascade Lake-AP for 2019

November 4, 2018

As part of the run-up to SC18, taking place in Dallas next week (Nov. 11-16), Intel is doling out info on its next-gen Cascade Lake family of Xeon processors, specifically the “Advanced Processor” version (Cascade Lake-AP), architected for high-performance computing, artificial intelligence and infrastructure-as-a-service workloads. Read more…

By Tiffany Trader

  • arrow
  • Click Here for More Headlines
  • arrow
Do NOT follow this link or you will be banned from the site!
Share This