For Utah Opera’s return, engineers study how air can flow safely through Capitol Theatre

(Photo courtesy of the University of Utah) Tony Saad, left, and James Sutherland, chemical engineers at the University of Utah, applied their research in "computational fluid dynamics" to create computer models of airflow on the stages of Abravanel Hall and the Capitol Theatre. The research is helping organizations make performance spaces safer amid the COVID-19 pandemic.

James Sutherland and Tony Saad have gotten to know the stages of Capitol Theatre and Abravanel Hall quite well — but they haven’t performed at those venues.

The two chemical engineers, researchers at the University of Utah and experts in “computational fluid dynamics,” are helping musicians of the Utah Symphony and Utah Opera perform with less risk of spreading COVID-19 to each other or their audiences.

“The basic question is: How do you reduce risk?” said Sutherland, a professor of chemical engineering at the U. “To answer that question, you need to know: Where is the air going? So you understand: If there are emissions occurring, where do those emissions end up?”

The engineers’ work was an aid in launching Utah Symphony’s season in mid-September in Abravanel Hall — and it’s being applied to the opening of Utah Opera’s 2020-21 season, on Friday, Oct. 9, the company’s first performances since the pandemic started in March.

Sutherland and Saad, an assistant professor, started by creating computer models of the Abravanel and Capitol stages, noting where the air vents were and how fast air moved through different vents. Once those models were built, they plugged in figures to represent musicians playing their instruments, with data provided by researchers at the University of Minnesota. Using the supercomputers at the U.’s Center for High Performance Computing, they figured out where respiratory droplets moved. And, more important, where they didn’t move.

Saad compared it to having to drive somewhere with a smoker in the car.

“First thing, obviously, you would open the windows, to just try to get all of that smoke out,” Saad said. “And you’d probably ask the smoker to sit closer to the window.”

In the traditional orchestra arrangement at Abravanel — violins toward the front, percussion along the back wall, brass and woodwinds in the middle — the modeling found that the droplets expelled by the horns and winds lingered.

The engineers found that by rearranging the musicians — putting the horn and wind players around the edges of the stage, where the vents were — and opening the doors at the sides of the Abravanel stage, the droplets and particles moved out.

“By opening the doors, we’re encouraging the air that is potentially infected with particles to leave,” Saad said. “And by rearranging instruments, we’re asking the ‘smoker,’ essentially, to sit closer to the window, where they’re more likely to just get those respiratory droplets immediately out of the chamber.”

Rearranging the opera

At the Capitol, the setup is somewhat different, because “the ventilation there is much, much older,” Sutherland said.

Christopher McBeth, Utah Opera’s artistic director, said that the stage configuration for the October shows will be reversed from the normal arrangement. The instrumental musicians, who usually play in the cramped orchestra pit, will take up the back of the Capitol stage. The singers will perform on the floor of the pit, which will be elevated to be flush with the stage. A scrim, on which scenery will be projected, will separate the singers and the orchestra.

In running their models, Saad said, it was harder in the Capitol to identify exit vents. “It was difficult to see where the air was going, if it was going anywhere.”

There are two large doors on the back wall of the Capitol stage, Saad said, but they’re too high up to pick up the air from the orchestra area. The engineers suggested a ventilation box — what folks in the HVAC industry call a “plenum” — to help carry the air to the doors and out.

(Images courtesy of University of Utah) A computer simulation shows airflow on the stage of Salt Lake City's Capitol Theatre, where the orchestra will be seated during performances of Utah Opera. The image on the left shows the projected airflow under normal conditions. The center image shows the airflow with the back doors of the stage opened. The image on the right projects the airflow if an HVAC plenum were to be built, to help suck air from the stage and out the doors.

Even with a “plenum,” the orchestra at Capitol will be different than usual. McBeth said the arrangements for the two one-act operas in the October program will mostly feature strings, “with heavy use of piano and percussion.” Those musicians, unlike brass and woodwind players, can mask up and still play their instruments.

The engineers were able only to assess the droplets and particles expelled by instrumental musicians. Sutherland — who is a member of the Tabernacle Choir at Temple Square, which also hasn’t performed since March — said singers are tougher to quantify, because their exhaled breath doesn’t go through a tube (like a clarinet or a trombone), and because they move around on stage, while instrumentalists usually stay in their seats.

The U. engineers’ research, Sutherland said, will provide “at least some insight into when they do put instruments in given positions, what that is doing in terms of the concentrations of aerosols in the air.”

In the early days of the COVID-19 pandemic, the act of singing was identified as a potential hazard. A story about a choir practice in March in Washington state — where one chorister with the coronavirus passed it on to 52 of the 60 other members attending — spread around the world as fast as the disease.

Research about whether singing spreads the coronavirus has been limited. One study by a university in Sweden, published in September, found that singing songs at top volume and with lots of consonants can spread droplets and aerosol particles that could carry the virus.

(Trent Nelson | Tribune file photo) The facade of the Capitol Theatre in Salt Lake City. Utah Opera will start its 2020-21 season at the Capitol on Friday, Oct. 9, 2020.

A smaller scale

The pandemic has forced McBeth to rethink one of the things that makes opera opera: its epic scale.

Utah Opera originally had planned to open the season with Richard Wagner’s “The Flying Dutchman,” one of the largest productions in classical opera.

“It would be 60 in the chorus, a good 50 in the orchestra, and another eight principal [singers], that would get a little tough with 120 folks, and keep them all together,” McBeth said. “That was too many people in too close quarters, for sure.”

Instead, McBeth programmed a pair of intimate one-act operas, both of which encompass themes of loneliness and isolation that are particularly relevant in our socially distanced lives.

“The Human Voice” is a 1958 work by the French composer Frances Poulenc, adapted from a 1930 Jean Cocteau play. The story centers on a woman on the phone with her lover, who is leaving her. (The Cocteau play, coincidentally, was adapted into a short film by Spanish director Pedro Almodóvar, starring Tilda Swinton, that premiered at the Venice Film Festival in September.)

“It’s the story of a young woman, struggling right now with the fact that she’s alone and desperate to reach out and have contact with another human being,” McBeth said. “It’s a piece that’s timely. We all understand that at another level now, after the last six months.”

The work will be sung in a contemporary English translation by soprano Wendy Bryn Harmer, a Utah native and veteran of the Metropolitan Opera — who McBeth had initially signed to perform the female lead in “The Flying Dutchman.” (Harmer will trade off performances with Edith Grossman, a resident artist at Utah Opera.)

“When we talked about doing this, she got very excited at the opportunity to add this to her repertoire,” McBeth said. (The Met, by the way, has canceled its 2020-21 season, and isn’t planning another production until fall 2021.)

The second opera on the program is lighter fare: a two-man comedy, “Gentleman’s Island,” written in 1958 by composer Joseph Horovitz and librettist Gordon Snell.

Based on a poem by W.S. Gilbert — before he teamed up with Arthur Sullivan to create such operettas as “H.M.S. Pinafore” and “The Pirates of Penzance” — the story follows Mr. Gray and Mr. Somers, two Englishmen who are stranded on the same desert island. They are reliant on each other for survival, but there’s a particularly English obstacle: They won’t speak to each other until they are properly introduced, and there’s nobody around to do that.

Two Utah Opera regulars, tenor Brian Stucki and baritone Christopher Clayton, play the Englishmen, with resident artists Daniel O’Hearn and Brandon Bell alternating.

“It’s not quite Monty Python, in terms of self-deprecation through humor, but we’re not far off,” McBeth said.

Safety measures

Utah Opera is implementing protocols in the audience: Spacing between family groups, mask requirements for anyone entering the theater, hand sanitizer stations, contactless ticketing, and no intermission between the one-act operas.

“People can feel particularly safe, and feel like they’re keeping that prescribed social distance that we all need to be practicing,” said McBeth, who added that about 200 or 250 tickets will be sold per performance, in a venue that usually seats 1,700. “Everybody’s going to have the best seat in the house.”

Saad, who has studied classical guitar, said it was exciting to take their research, which can get quite academic, and use it in a practical setting.

“Music is one of the first things humans invented. Percussions and sound. It’s so elemental for people to be able to listen to music, especially in these days,” Saad said. “It gives hope. It’s a single piece of good news in this insane year.”

Utah Opera returns

Utah Opera begins its 2020-21 season with two one-act operas: Francis Poulenc’s “The Human Voice” and Joseph Horovitz’s “Gentleman’s Island.”

Where • Capitol Theatre, 50 W. 200 South, Salt Lake City.

When • Premieres Friday, Oct. 9, at 7:30 p.m.; other performances are Saturday, Oct. 10, at 1 and 7:30 p.m.; Monday, Oct. 12, at 7 p.m.; Wednesday, Oct. 14, at 7 p.m.; Thursday, Oct. 15, at 7 p.m.; Friday, Oct. 16, at 7:30 p.m.; Saturday, Oct. 17, at 1 and 7:30 p.m.; and Sunday, Oct. 18, at 2 p.m.

Tickets • Availability limited due to COVID-19 restrictions; some shows are sold out. Tickets, ranging from $20 to $110, can be purchased online at Arttix.org.