Author: Blair Johnson

We’ve had a lot to celebrate this past year, so let’s touch on some of the highlights!

Summer 2023 was relatively calm but full of learning. Aubrey worked tirelessly to finish her dissertation, while Po-Chen persisted with data analysis and testing of a new turbulence sensor (details hopefully forthcoming, pending our next tests!). Meanwhile, Arefe spent the summer at the WHOI GFD program, as a Fellow!  She spent the summer back in the land of numerical modeling, looking at internal waves and all things stratified. I got to visit for two weeks of seminars and time with collaborators, and loved spending some time in Cape Cod.

In August 2023, the JETlab graduated our first* Ph.D., the fabulous Aubrey McCutchan!  Her defense went smoothly, and was an extremely proud moment as she taught us all about ice melting in turbulence, and her hopes/goals to integrate her findings into glacier melt models and improve the accuracy of models so we can all get a more realistic view of sea level rise. Sadly we forgot to take a photo of the big moment (here is one from when she started 5 years ago!), but all the forms were signed to make it official. Aubrey’s second paper was published in the Fall, about her homogeneous isotropic turbulence tank that she tuned to perfection.  (*I’ll also note that we also minted a Ph.D. a few years back with Yongsik, who started his grad school studies with colleague Ben Hodges. Ben and I co-supervised Yongsik as he wrapped up his dissertation … so Aubrey is the first Ph.D. from start to finish in our group!)

The JETlab briefly shrunk by 1, with Aubrey’s graduation. Then we quickly brought in two new students in September – welcome Biman and Hiromu! Biman is starting his Ph.D., studying buoyant plumes on our NSF-funded project (with collaborator Alexis Kaminski at Berkeley). He’s been diligently going through data that I collected with Po-Chen, Riley, and Ella, as he is  learning all about image processing. Hiromu is starting his Masters and has taken over Aubrey’s turbulence tank. Just this week he set up our PIV system again, and we’ll have ice back in the tank soon for our next set of experiments!

In November, Arefe and I traveled to Washington, D.C. for the APS-DFD conference, where we got to reunite with many of our favorite fluid mechanicians, including former-JETlabber Julio! I presented Aubrey’s latest ice melting experiments (paper coming soon, fingers crossed…) and Arefe gave a killer talk on mixing in stratified turbulence. The three days flew by with lots of knowledge, laughter, and wonderful connections. After APS, I squeezed in a little Thanksgiving excursion, and then got to attend the SERDP Symposium in Arlington. It was great to connect with lots of sediment/nearshore folks, and see the NRL-Stennis crew in full force.

We have one more key celebration from December, with the publishing of Arefe’s first paper! Her review paper is now in the new journal Flow, and we hope it’ll be a great resource for experimentalists and modelers alike who are interested in turbulence generation. Cheers to Arefe.

We all got a little bit of rest over winter break, and then in January welcomed another new Masters student, Alexandra Stephens!  Alex has joined our Army Corps / USCRP project and is getting up to speed on surface PIV, turbulence, waves, and swash dynamics. She’ll be running tests in our large outdoor flume in preparation for experiments at ERDC next summer, with a great team led by Ryan Mieras at UNC Wilmington. We also had a fun two-day set of tests on our outdoor flume working with a Houston-based company.

It’s been extremely fun having the group back to 5 members this semester, and to have so much energy in the lab with all of our projects running in various stages. We’ve also had a shuffling of our undergrad research assistants, with Riley stepping down this semester and Ella jumping back in, after returning from a semester abroad in Spain, and Kavya joining the crew with a research fellowship from the department.  We have a few papers in review right now, and are doing our best to share the discoveries of the JETlab with the world. I have also officially kicked off the process of applying for tenure, and am asking for all good vibes and crossed fingers throughout the process. Arefe, Po-Chen, and I will be seeing y’all at Ocean Sciences a week from now, and I’ll get back to posting our updates when I can!

UT adjusted the academic calendar this year, meaning we’re already a week into “summer” in Texas! A lot happened this semester. We won some grants (woohoo, NSF CAREER for stratified mixing! And some others that aren’t yet “official” so we’ll stay hush…). We submitted two papers from the JETlab – both very turbulence-focused, my favorite!  And one more for a UT Geosciences student who did fascinating experiments on lofting density currents – fascinating (and difficult) experiments. Aubrey melted her beautiful clear ice spheres in spectacular fashion, and are in the midst of testing a new turbulence sensor. Arefe was offered a position at the WHOI GFD program for this summer, and we could not be more proud of her being selected!

Thankfully travel mostly subsided after a very busy Fall and Winter of seminars and conferences for all of us. I still got to see a few of my favorite colleagues and collaborators at small meetings this spring. I was asked to serve on a PhD committee for a Music Composition student — and now it is my goal to serve on ALL of the music PhD committees, because the students are so immensely talented, and the “exam” includes a free concert!  No better way to spend an evening.

And ….. we finally resurrected the 1972 flume!  Po-Chen and I wrapped up final details — sealing up the ends, and installing a drain — and filled the flume at the start of May. The first day (only with maybe 1/2″ of water) there were no leaks! But also the water was going straight to the drain/sewer, since we didn’t have a way to plug the pipe.  Then once we closed it and could do a proper fill the following week, a few little Niagara Falls opened up.  But for the 22m (give or take a few … we need to measure) length, with some amateur flume-retrofitters, I think we did a spectacular job. We still have a few fixes to come – somehow wires got crossed so the pump now flows BACKWARDS (you can’t make this stuff up…), and the motor smells like fire… realized it hasn’t been tended to in at least 25 years, if not more?  And of course, leaks to fix. But water is moving, and I am pretty proud that we’ve made it this far on a very bare bones budget, with zero “professional” help.

I am more than ready for summer! Our 3 PhD students are doing fantastic work – with our first anticipated graduation in August!  I am looking forward to many more flume days, leaks included, as we do the final touches to say we successfully retrofit a flume. I’ll have a brief trip to WHOI and a couple little vacations. And hopefully several more paper submissions before our new JETlab students join us in August.

It has been a whirlwind batch of months for the JETlab, so we are long overdue for an update. We have all logged a LOT of airline miles this year! We’ve all continued to dig further into our turbulence research, and are starting to see the light at the end of the tunnel (cough cough, papers and graduation dates!) for a few of us!  Some of our highlights:

Blair returned from NRL Stennis in August with a renewed zest for lab work, since she finally ran her own experiments and got to learn how to do tomographic PIV, while playing with all sorts of wonderful equipment and with fantastic mentors and collaborators. Her semester was subsequently filled with seminars galore — presenting the group’s research at various universities and getting to visit other labs — always a joy. It is a delight to meet with the faculty and graduate students at different universities, and to feel inspired by the innovation happening everywhere. In Fall 2022, Blair visited the Woods Hole Oceanographic Institute, Johns Hopkins University (her alma mater!), CalTech, and MIT. This spring, Blair has already visited the University of New Hampshire, and heads to the SAFL lab this coming week — high on her bucket lists of super awesome labs to visit! We hope it lives up to her expectations!!

We also had lots of conference travel. Po-Chen ventured solo to the Young Coastal Scientists and Engineers Conference in Pensacola in October, and then to the American Geophysical Union Fall Meeting in Chicago in December. Aubrey, Arefe, and Blair went together to the American Physical Society – Division of Fluid Dynamics meeting in Indianapolis in November (brr!!!), where we got to reunite with JETlab alum Julio (presently at UW for his PhD!) and lots of other friends.  Blair also had a rapid trip to DC for the SERDP Symposium in December. Everyone’s talks and posters went fabulously at all of their visits, and it is exciting to see everyone continuing to grow their networks and gain inspiration for new ideas and future paths through these opportunities.

Our famous 1972 flume is soooooooo close to being done!  All that remains is to seal up each end, where the glass and acrylic join up with the original steel plates, and to fit a tube into the mystery-threaded drain at the bottom. Please keep all fingers and toes crossed for when we add water in very near future!! Moment of truth, whether it was all worthwhile. We hope so!

We are on the cusp of submitting several papers on the excellent research happening with our turbulence tanks, so stay tuned. We also have two new undergraduate researchers, Riley and Ella, who have been a joy to work with as they learn about lab work and image analysis. We are also hoping to welcome a few new faces to the JETlab for Fall 2023, and can’t wait to see how our admissions process continues! Lots to come …

It’s been a big semester for the JETlab!  We are excited to report a newly-minted Masters of Science for James Holyoke, who wrote a fantastic thesis covering two important topics – design of portable median barriers for flood zones, and tracking edge features in buoyant plumes to develop remote sensing techniques.  James will be sorely missed at UT, but we are glad to have had two years of work together in Austin! Congrats, James!

We also have three Ph.D. candidates in the group, with Po-Chen passing his Quals last semester and successfully applying to Candidacy this spring!

What else happened this semester?  Arefe and Blair virtually attended the Ocean Sciences Meeting that would have been held in Hawaii if we weren’t still in the midst of a global pandemic.  Arefe gave an excellent talk on stratified mixing in the Nearshore Processes session, and Blair presented Po-Chen’s project on sediment transport.  Meanwhile, Po-Chen and Blair wrapped up their SERDP project with lots of glorious freeze-coring of colored sands and some sneaky PIV maneuvers, which we’re still going to keep under wrap until we work out some bugs!  But it was a fun semester with lots of lab experiments and tons of learning.  Everyone is in the midst of writing papers and running tests, and blossoming into talented, capable, and confident scientists.   We also enjoyed a number of happy hours and dinners to stay sane along the way 🙂

And finally, we’ve made progress in renovating our 1972 flume, after MANY years of frustration and preparations.  We aren’t done yet, but stay tuned to Blair’s twitter for updates – #JETlab and #1972flume will show you all you need to know.

Blair is presently enjoying the start of summer living in New Orleans and working at the Naval Research Lab at Stennis as an ONR faculty fellow.  She (I … I never know whether to write this in first person or third!) was thrilled to receive the CAEE department teaching award this Spring semester, and is determined to go into year 5 at UT with lots of hope for wonderful things to continue.

We are thrilled to wrap up 2021 with several celebrations across the group for a successful semester, despite the ongoing pandemic, continued lab renovations, and the odd things that keep experimental fluid mechanics researchers awake at night.  Some of our highlights include:

In October, Ph.D. candidates Aubrey and Arefe traveled to the Young Coastal Scientists and Engineers Conference in Myrtle Beach, SC, where Aubrey won an award for her excellent poster on turbulence and ice melting, and Arefe gave a fantastic oral presentation of her stratified mixing research. Well done, friends!

Arefe and I then traveled to Phoenix, AZ, for the American Physical Society – Division of Fluid Dynamics meeting in November. This was my first in-person conference in 21 months, and I could not have been more excited. Arefe did a fantastic job presenting her poster and meeting some of the folks we’ve only read about. It was an incredible joy to share science together and to have so many meals and outings with our colleagues and friends we’ve missed so dearly.

One of my favorite things that has blossomed during the pandemic (but hopefully will stick around for years to come!) is a weekly writing group between women fluid mechanics professors at various institutions. We finally met in-person together for the first time at APS, and I can honestly say I have not smiled that big in years. We’ve been through many paper/proposal submissions, acceptances, and rejections together, and it is comforting to have the support of such brilliant and kind people on a regular basis.

With that, let’s wrap up 2021 and continue on next year. Loads of gratitude for my students and colleagues who make this job such a joy!

It has been a minute since we’ve updated the site — and we owe belated congratulations to Julio Chavez Dorado on completion of his Masters thesis this summer!  Julio was a valuable member of the JETlab for the past 2 years on a Fulbright scholarship.  His work on surface velocimetry in our outdoor flume was tricky, but he was determined throughout and learned a ton about image processing along the way.  This past month, Julio traded Austin for Seattle to begin his PhD at the University of Washington!  We will miss him dearly, but are so glad he’s staying in Fluid Mechanics so that we can continue to rendezvous at conferences in the coming years.

With Julio’s graduation, the JETlab is down to 3 PhD students (all of whom have passed their qualifying exams, WOOHOO!) and 1 Masters student, but we’ve gained several wonderful new undergraduate members!  I realize we missed doing a formal post to welcome Po-Chen to our crew — he had a staggered start, due to international travel restrictions and Visa delays thanks to the pandemic, but he’s been in Austin since January already and we are so glad to work with him.  I am happy to report that we’ve finally recovered to what feels like “normal” lab operations for the first time since the pandemic shutdown in March 2020. I am also thrilled that we are allowed to have undergraduate researchers in the lab again — it was such a loss having those personnel restrictions in place.  Of course we acknowledge the safety concerns, but it really stank.  Hopefully soon it will all be a distant memory.  We are still doing many zoom meetings, but all get to cross paths in the lab and for occasional celebratory dinners.

In the mean time, experiments are going strong – fluorescent dyes all over the place to visualize stratified layers in turbulence mixing experiments, to visualize plumes to develop remote sensing techniques, and much more.  We have several in-person conferences coming up this Fall for the first time since winter 2019/2020, and can’t wait to see our friends and colleagues in 3D again!

Howdy all, and welcome to the end of spring semester!  There were many highlights and causes for celebration this semester, though sadly several of those didn’t get to happen in person due to covid19.  Let’s list a few of them to share the joys (and acknowledge the non-joys) of Spring 2020.

In February, I attended the Ocean Sciences Meeting in San Diego!  It was wonderful to see my Nearshore friends and colleagues all in the same room – definitely got the wheels churning for future projects and collaborations.  If only there were more time!  I was also thrilled to reconnect with several of my EFMH colleagues from Cornell, pictured here.  I had planned an extra weekend mini-vacation with that trip — and I am glad it happened, because little did we know travel would be halted indefinitely with the rapid spread of coronavirus.  Logged many miles exploring southern California’s beaches and consumed a LOT of fish tacos.

In March, we had to put the JETlab to sleep.  We initially stayed open through Spring Break with many social distancing and safety requirements in place.  While we were still running, on March 19, Aubrey finished building her new tank and a fantastic addition to the lab – our mini homogeneous isotropic turbulence tank, presently called the J-20 for the 20 jets that run it.  She was able to collect lots of PIV data, and then on March 24th, 3pm, we locked it up not knowing when we’d be back.  Sweet dreams, turbulence!

Zoom meetings commenced, and thankfully we all stayed healthy and relatively happy.  Some new hobbies emerged, post-seminar zoom happy hours were held, and we all made the most of it.  (And we are still doing this, as I write!)

In April, we had several bits of awesome JETlab news.  Aubrey was awarded the NSF GRFP, which means she has full funding to move forward with her PhD!  I could not be more proud – she’s incredibly deserving and has a bright path ahead for sure.  Congrats, Aubrey!

I was relieved to have a JFM paper published – finally all of my PhD work is “officially” done, years after graduation.  We can share videos of sand and turbulence and all of it now, no secrets left!  I was also awarded another grant for the lab, so we may continue studying median barriers in flood-prone areas, a project that we hope continues to evolve so we can better serve our coastal communities in Texas .. and elsewhere.

Then May emerged – with three of our JETlabbers officially becoming Masters of Engineering!  Congratulations to Hannah, Greg, and Aubrey for writing fantastic theses of your work over the past two years.  Admittedly we were not able to “finish” some parts due to the lab closure, but they all did excellent work from day 1. I am sad to see our group shrink – Greg will be moving on to complete his PhD with Lina Sela – thankfully still in the same building – but will be switching over from experiments to remote sensing.  Hannah will be working for Exxon (staying in Texas, mostly, woohoo!) and Aubrey will be a PhD student in our group, effective immediately.  Two years with them absolutely flew by.  They’ve taught me a lot and have brought a lot of laughter and great memories to the lab.  Sadly we don’t have a group graduation photo, but here are some of my favorite action shots with them.

And with that, we’ve concluded another semester of research, writing, teaching, seminars, conferences, etc.  We’ve probably made about 8,247 mistakes in the lab thus far, and that number will only continue to rise once it’s safe for us to continue working in there again.  Cheers!

Happy new year, folks!  It was a busy and wonderful Fall semester in the JETlab – it flew by, with many travel highlights along the way, some of which include:

September:

• THESIS2019 conference at the University of Delaware (thanks to Tom Hsu!), where Hannah gave her first presentation and poster, and we nerded out with our favorite sediment transport friends from around the world.

 

• JETlab group dinner!  We welcomed two new students, Arefe and Julio, to the crew.

October:

• I visited UIUC to give a seminar, toured my PhD colleague Rafael Tinoco‘s amazing EEL lab, then Rafael came to UT the next week to do the same!
• I officially started my first lead PI grant, from SERDP!  It’s a one-year SEED grant, involving fluidization of a sediment bed in turbulence and the potential to exhume buried munitions .. stay tuned.

November:

• APS-DFD conference in Seattle with my favorite fluid mechanicians!  Part of the Cornell EFMH crew (+ Berkeley) pictured.

• Gave seminars at the University of British Columbia and Simon Fraser University, with Thanksgiving spent wandering around downtown Vancouver, gorging on sushi and oysters. Many thanks to Greg Lawrence, Jason Olsthoorn, Jeremy Venditti, and Lizzie Dingle for making my Canada trip happen and showing me your fabulous labs!

December:

• Traveled to the SERDP-ESTCP symposium in DC, which was wonderfully eye-opening on the DoD’s environmental interests.
• Traveled to the AGU Fall Meeting in SF, where Luisa, Aubrey, and Greg gave fantastic talks and posters.  And I guess I did too, in the #FlumeFriday session.  Caught up with many of the Cowen EFMH crew from Cornell, always a great time.

We also have two December graduates of EWRE from the JETlab.  Luisa Florez and Andrew Jaeger successfully completed their MS degrees, woot woot!!  Starting in January, Luisa will be working for BP in Houston, and Andrew will be the lead Engineer of the Coast Guard in Corpus Christi. I’m selfishly glad all my graduates have stayed in Texas so far, since it means I don’t have to say goodbye yet.  We don’t have a December ceremony, so … no graduation photos, sadly.

A few of us did a little hike at McKinney Falls State Park over winter break:

There were many other memorable moments in the lab – joyful, curious, disastrous, and hilarious.  I’m very thankful to my students, as always, for their positive attitudes, troubleshooting skills, and love of learning.

Cheers to a wonderful start to 2020!

With the end of the semester, we have some exciting news and a few farewells!

Many many congratulations to my very first Masters student, Junior Lagade, Jr., who submitted a lovely thesis and made my first year and a half as an assistant professor a true joy.  Junior will be staying in Austin to work as an environmental engineer, and I am hoping to finally attend one of his hip-hop dance classes.

Huge congratulations also to Yongsik Kim  for a fantastic Ph.D. defense and graduation!  Yongsik did a dam-good project (ha..) on pressure flushing and I hope we can still rendezvous on future travels.  Yongsik is working in South Korea and in charge of many dam projects throughout the country.  We sadly didn’t get a graduation day photo.

It has been a productive and fun semester in the lab, playing with liquid nitrogen, getting sugar pretty much everywhere, using intense black lights, watching tadpoles come out of the flume pumps, all sorts of joys that I’ll eventually update on the Research page.  We are making progress having more and more tanks in the lab and trying to plug the million leaks that go along with them.  Stay tuned to #flumefriday posts on Twitter for the good stuff.

Thanks for an excellent semester to my 2018 and 2019 JETlabbers!  (Yongsik we will photoshop you in from Korea one day!)

After many many hours of sledgehammering, drilling, shoveling, and carrying out tons of rocks, sand, rotten wood, and the works, the outdoor flume is back in action.  This is a very beautiful sight, thanks to the dedication and hard work of a crew of undergraduate civil engineering students (thanks to Kelly, Lorenzo, Marco, James, Sanjiv, and Jhoneil) and all my current JETlab students (Junior, Luisa, Greg, Andrew, Hannah, and Aubrey).  It looks brand new.

 

Thankfully we had some great 80+ degree weather in the middle of February to finish everything up.

One final before shot:

 

 

 

 

 

 

And some action shots:

 

 

 

 

 

 

 

 

 

 

We’ll be putting some test median barriers in here in the next month or so — stay tuned!