Remembering Stanford ‘Sol’ Penner, a Founding Engineering Professor at UC San Diego

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Stanford S. “Sol” Penner Photo credit: UC San Diego Jacobs School of Engineering

Professor Emeritus Stanford S. “Sol” Penner, one of the founders and creators of the engineering program at the University of California San Diego, passed away on July 15, 2016 at his home in La Jolla, Calif. He was 95 years old.

Penner’s research program was broad and included work that profoundly influenced the design of liquid propellant rocket engines used for space exploration.

In 1964, Penner joined the UC San Diego faculty and became the first chair of the campus’ first department of engineering. The department was named AMES -- the Aeronautical and Mechanical Engineering Sciences Department (aeronautical later became aerospace). As AMES department chair, Penner hired or helped hire many of the profoundly influential professors who worked together to build what grew into four of the Jacobs School of Engineering’s six academic departments: Bioengineering, Mechanical and Aerospace Engineering, NanoEngineering (which includes chemical engineering), and Structural Engineering.

In 1973, he created the Center for Energy Research at UC San Diego as a place for researchers from across campus and around the world to come together to pursue critical, interdisciplinary energy research.

“We have lost one of the most brilliant minds and one of the pillars on which UCSD is standing. We have had many illustrious colleagues during these 50 years since the formation of UCSD, but one can say with total honesty that very few have been as loved and admired as Sol Penner, especially among all of us in engineering. Sol Penner was not only our founder and leader, but he was a generous colleague and a dear friend to many of us,” said UC San Diego distinguished mechanical and aerospace engineering professor Juan C. Lasheras.

In 2004, in a Jacobs School of Engineering publication, Penner described some of what drew him to UC San Diego in the early 1960s. “After that first visit and meeting with the principal designers of the new campus in the beguiling environment provided by the La Jolla location, I was totally convinced that a great university would be the result. Also, I was enthusiastic about the exciting opportunity of founding a single department where engineers and applied scientists from many disciplines could interact with colleagues while working on common long-term goals. The innovative programs were especially appropriate at the height of the Cold War when there was a strong demand for Ph.Ds. in advanced engineering and applied science R&D,” he said.

Penner is recognized worldwide for his research contributions and expertise in a wide range of areas including thermophysics, applied spectroscopy, propulsion, combustion, and a variety of topics in energy. His theoretical and experimental work on relaxation processes in nozzle flows, propellant burning, laminar flames, droplet burning and ablation profoundly influenced the design of liquid propellant rocket engines used for space exploration.

Building engineering excellence at UC San Diego

From 1964 to 1968, Penner served as the chair of the Department of Aeronautical and Mechanical Engineering Sciences (AMES). As department chair, he attracted an impressive group of highly distinguished faculty in fluid and solid mechanics, systems and control engineering, structures, ocean engineering, chemical engineering, bioengineering, materials science and aerospace engineering.

"Sol was a great scientist-engineer and a tremendous leader. He always had great vision and the abilities to recognize talents and seize on opportunities,” said Shu Chien, a Distinguished Professor of Bioengineering and director of the UC San Diego Institute of Engineering in Medicine.

In 1965, in response to Y.C. Bert Fung and Benjamin Zweifach’s proposal to establish a program in Bioengineering, which as a field of study was in its infancy, Penner asked them to come to UC San Diego to start this novel interdisciplinary program in AMES. In 1966, Fung and Zweifach joined UC San Diego, along with Marcos Intaglietta. Y.C. Fung went on to become widely known as the father of biomechanics. Fung won the National Medal of Science, he is a member of all three National Academies, and he is part of the team that built one of the top bioengineering programs in the world.

Bioengineering is just one example of Penner’s legacy at UC San Diego. Penner brought to UC San Diego not only his scientific talent and a full complement of state-of-the-art facilities but also a pioneering spirit. To create solid and structural mechanics, Penner attracted Bill Prager, a giant in the field. Penner and Prager helped to recruit a number of young faculty, including Gil Hegemier, who was part of the team that went on to create the Powell Structural Research Laboratories and the Englekirk Structural Engineering Center at UC San Diego; and Sia Nemat-Nasser who helped create the materials science graduate degree program at UC San Diego.

“Penner had a clear perception of the potential of young people and once they joined the team he provided the opportunity to do creative work and make fundamental contributions. Thus, within a few years UCSD had become well-known world-wide for being the hot-bed of engineering sciences,” said Sia Nemat-Nasser, Distinguished Professor of Mechanics and Materials, and Director of the Center of Excellence for Advanced Materials at UC San Diego. 

Penner’s vision was to create a group of distinguished experts who would cooperate on interdisciplinary studies without departmental boundaries while simultaneously developing their own areas of expertise. 

“The consequences of this visionary investment cannot be more apparent,” said Lasheras.

When Penner stepped down as AMES department chair in 1968, the department was already recognized as one of the leading Engineering Sciences departments in the nation. In 1971, only seven years after its creation, the National Research Council of the National Academies ranked AMES in the top 10 Aeronautical Engineering Departments in the nation.

This legacy remains. The bioengineering seeds that Penner planted grew into what is now the top bioengineering department in the nation according to the most recent survey by the National Research Council of the National Academies. Penner was also instrumental in building up what grew into the departments of Mechanical and Aerospace Engineering, NanoEngineering (which includes chemical engineering), Structural Engineering -- all of which are influential and highly ranked.

“Sol was a visionary and giant, not only in the AMES department and at UCSD, but in all of engineering, and far beyond,” said UC San Diego mechanical and aerospace engineering professor Frank Talke.

Center for Energy Research

From 1971 to 1972, funded by a Guggenheim fellowship, Penner visited colleagues in Europe, Asia and Australia. He returned to UC San Diego convinced that issues of energy, ecology and economy would provide a major challenge to the physical well-being of people everywhere. The following year, he founded the UC San Diego Center for Energy Research and served as its director until 1990, when the directorship moved to UC San Diego professor Forman Williams, who had been Penner’s graduate student at the California Institute of Technology (Caltech).

From the early 1970s on, Penner devoted much of his time to energy conservation, fossil-fuel development, fuel-cell design, and environmental issues in the United States and abroad. In 1975, he founded Energy, the International Journal. He served as editor of the journal until 1998.

Sol. Penner (left) and student. Photo published in AMES graduate program brochure from the 1960s. Original photo caption: Ionization rates of metals influence the radar returns from missiles and space vehicles. They may be measured in shock tubes with proper diagnostic tools. Photo credit: UC San Diego Jacobs School of Engineering

Research and publications

Penner is recognized worldwide for his expertise in thermophysics and his contributions to propulsion, combustion, thermophysics and basic energy systems. His theoretical and experimental work on relaxation processes during nozzle flow, propellant burning, laminar flames, droplet burning, and ablation has profoundly influenced the nozzle design, scaling, and stabilization of liquid rockets.

He was elected to the National Academy of Engineering in 1977 for his “contributions to aerothermochemistry and its application to combustion theory, radiative heat transfer, and reentry phenomena.”

Thirty years later, in 2007, Penner won the National Academy of Engineering’s Founders Award as recognition for “pivotal studies on thermal radiation, directing government studies, founding a university department and energy center, and training future leaders.”

At the time of his retirement, Penner had published over 320 peer reviewed journal articles, seven books, 10 monographs, and had edited 10 books. In 1957 alone, he published several seminal books including Quantitative Molecular Spectroscopy and Gas Emissivities and Chemistry Problems in Jet Propulsion. 

In 1960, he founded the Journal of Quantitative Spectroscopy and Radiative Transfer serving as chief editor for over 30 years.

One of those future leaders was UC San Diego mechanical engineering professor Forman Williams. “Sol had more of a positive influence on my career than anyone else by far,” said Williams, who described Penner’s breadth of contributions in engineering science as “extraordinary.”

The list of national and international awards and honorary degrees awarded to Penner also includes the prestigious Distinguished Associate Award from the U.S. Department of Energy and the Edward Teller Award for the Defense of Freedom. He is a member of the International Academy of Astronautics and a fellow of the American Academy of Arts and Sciences.

Biographical information

Stanford S. “Sol” Penner was born in Unna, a small town in the North Rhine-Westphalia region of Germany on July 4, 1921. He came to the United States when he was 15 years old. As a child, he was always interested in art and humanities, and his first ambition was to become an artist and a poet.  Although he dedicated his life to science and technology, he continued following his early passion for the arts. He was an avid collector of art and accumulated an impressive collection of paintings and sculptures; notable among them is a collection of Chinese hardstone carvings that has been exhibited in several museums.

After finishing high school and earning an undergraduate degree in chemistry from Union College in 1942, he joined the Ph.D. program at the University of Wisconsin to work with Farrington Daniels, a well-known physico-chemist. Penner became involved in solid-propellant rocket engine research.

During WWII, he joined the Allegany Ballistic Laboratory in West Virginia where he was responsible for a rocket test-firing range. At the end of the war, Penner returned to the University of Wisconsin and completed his Ph.D. in 1946. His early propellant and radiation heat transfer studies were the beginning of a long lasting research program in combustion, applied spectroscopy and gas emissivities that extended over 60 years.

After a short postdoc at ESSO Research Laboratories in Linden, New Jersey, he joined the Jet Propulsion Laboratory in Pasadena and was later appointed to the faculty of Caltech as a Professor of Jet Propulsion. While at Caltech, he made outstanding contributions to radiative heat transfer, gas spectroscopy and chemically reacting flows in jet propulsion. He served as director of the Research and Engineering Division at the Institute for Defense Analyses in Washington, D.C. from 1962 to 1964 while on leave from Caltech. In 1964, he joined the UC San Diego faculty and remained on the UC San Diego faculty for more than 40 years.

Penner contributed to UC San Diego in many ways beyond his exemplary research, teaching, advising and academic leadership at the department level. His work included a stint as UC San Diego Vice Chancellor of Academic Affairs.

In 2000, through a generous donation, Penner established the endowed Stanford S. and Beverly P. Penner Lecture Series in the Department of Mechanical and Aerospace Engineering. He conceived the lecture series as a continuation of the early days of UC San Diego, when every new faculty member was invited to give a lecture to the entire faculty and student body—from all departments.

In 2008, thanks to another generous donation, Penner created the Stanford S. & Beverly P. Penner Endowed Chair in Engineering or Applied Science in the Department of Mechanical and Aerospace Engineering at the UC San Diego Jacobs School of Engineering. The inaugural holder of the Penner Chair is Juan C. Lasheras.

“We will always hold Sol Penner in a very special place in our heart. He was not only a great mentor to many of us but a very dear friend,” Lasheras said.

On November 5, 2015 the Mechanical and Aerospace Engineering department dedicated the von Kármán-Penner seminar room at UC San Diego. Penner was close collaborator of Theodore von Kármán, the world renowned mathematician, aerospace engineer and physicist.

“The dedication of our conference room to von Kármán and Penner honored their approach to science and engineering which combined academics, government and industry to promote knowledge in ever new directions for the benefit of humankind. Penner helped bring this approach to engineering at UC San Diego and in particular to the Mechanical and Aerospace Engineering department, that MAE continues today,” said Vitali F. Nesterenko, professor and chair, UC San Diego department of Mechanical and Aerospace Engineering.

Penner is survived by his younger brother Bernhard, his children Robert and Lynn with her husband Christopher Clague, his grandchildren Michael with his betrothed Jesse McDougal and Kirby with her husband Joshua Lottman and their children Flynn and Everleigh.

The family suggests that any gifts in Sol Penner’s honor be made to the Jacobs School of Engineering at UC San Diego.