Daniel Rosner

Daniel Edwin Rosner, of Woodbridge and Hamden, CT, passed away on February 3, 2025 at the age of 91 years, with his wife Susan, son Stefan, and grandson Zachary by his side. Dan was born in The Bronx, NYC, in late-October of 1933, to Samuel and May Rosner. Dan was athletic, with a mean stickball pitch that proved effective in the narrow streets where he lived and attended P.S. 64, two "El" stops north of Yankee Stadium. Dan also had a keen eye as well as an appreciation for – and natural ability in – the arts, particularly graphic arts and printmaking. Dan developed a burgeoning portfolio of artwork, and was accepted to the High School of Music & Art in upper Manhattan, where he soon became the art editor of the high school newspaper, and ultimately for the school yearbook for his senior year. While at the High School of Music & Art, Dan made several very close friendships that – quite remarkably – endured for nearly 3/4 of a century, right up until his final days. He graduated in 1951 with the Phi Beta Kappa Alumni Award, as well as the prestigious Saint-Gaudens Medal for art. Though he clearly possessed the talent and interest to pursue a successful career in the graphic arts, he instead decided to enroll in Brooklyn College so that he would have access to a full academic program while still pursuing a fine arts degree. But by this time, his interest in pursuing a career in the arts had started to wane, as the art and artists that were attracting the attention of art critics and the public seemed to him more like scribbles and paint splatters in stark contrast to the works of the Renaissance and post-impressionist "realists" that he truly appreciated. At around this same time, progress in liquid propellant rocketry and jet-engine flight had sparked his interest, and from a physics professor, he learned of a graduate / research program in jet and rocket propulsion at Princeton University. He opted to transition to engineering, and transferred to City College of New York (CCNY) to finish up his undergraduate degree, graduating summa cum laude with a BS in Mechanical Engineering in 1955. Dan met his true love, Susan Daniels, also a student at CCNY, with their courtship enabled by frequent weekend train trips while Dan pursued a PhD in the Aeronautical Engineering program with a Guggenheim Fellowship at Princeton University. Dan and Sue married in Aug. 1958, and by the time he was awarded his PhD, they had started a family with the arrival of their daughter Lisa in 1959 and their son Stefan in 1961. While Dan worked in the aerospace industry in Princeton, NJ for several years, he was recruited for a faculty position at Yale University in New Haven, CT, becoming a Professor of Chemical and Environmental Engineering, with a joint appointment in Mechanical Engineering, twice serving as department chair. Dan's textbook, Transport Processes in Chemically Reacting Flow Systems is widely used for teaching Transport Phenomena in chemical engineering departments across the country, and won the American Society of Engineering Education award in 1988. He received the David Sinclair lifetime achievement award from the American Association of Aerosol Research in 1999, an honorary doctorate from the Universidad Nacional de Educatión a Distancia in Madrid in 2002, and the Particle Technology Award from the American Institute of Chemical Engineers in 2011. In 2005, Dan was nominated to the Connecticut Academy of Science and Engineering and was awarded the Llewellyn West Jones, Jr. Chair of Chemical and Environmental Engineering. While teaching at Yale, Dan directed the dissertations of 23 PhD students from all over the world. He published over 280 scientific papers on problems in chemically reacting flows, aerosol science, and other broadly related fields, conducting experiments and computations and developing useful analytical models for industrial applications. He stayed in close touch with his students, and remained active in research as a Senior Research Scholar and emeritus professor well past his retirement from Yale in 2014, continuing to publish several papers each year. Dan's research was unusually eclectic and multidisciplinary in nature, impressive in both breadth and depth. Engineers at NASA sought Dan's expertise on high-temperature reacting flows for the Space Shuttle Orbiter's siliconized pyrolytic carbon wing leading edge and nose cap thermal protection tiles, developed to withstand the extreme conditions of hypersonic reentry. Dan also conducted wind-tunnel experiments and heat transfer computations on the plates of Stegosaurus in collaboration with the Department of Geology and Geophysics at Yale and the Peabody Museum of Natural History. This work formed the basis for the current hypothesis that the primary function of these plates was most likely thermoregulation, and not – as previously supposed – for armor or sexual display. The resulting paper, Plates of the Dinosaur Stegosaurus: Forced Convection Heat Loss Fins? was published in Science magazine (June 1976) with Dan's meticulous hand-rendered etching of Stegosaurus on the journal cover, evoking his roots in the graphic arts. Indeed, while Dan was quite involved with his family and career in academia, his interest in artwork never waned. He continued to create wood- and linoleum cut Holiday cards with his children, and even honed his skills in new media, including pen & ink drawings and watercolor painting, often combining these into mixed-media pieces. Dan's signature woodcut prints of industrial settings and watercolor paintings of Yale architecture are familiar to many in the community. A collection of his art can be admired at the Koerner Emeritus Faculty Center at Yale. It is perhaps not surprising that both of Dan's children ultimately pursued degrees and careers in engineering, noting that his son additionally "minored" in the graphic arts, with concentrations in photography, serigraphy and lithography. Dan is deeply missed by his family, longtime friends, colleagues and former students. He is survived by his loving wife of 66 years, Susan, daughter Lisa, son Stefan and daughter-in-law Julaine (Herreid), grandchildren Zachary and Paloma, and loyal dog Panda. A private memorial remembrance of Dan will take place this spring. He will be laid to rest at that time, in the good company of other luminaries and friends, at the historic Grove Street Cemetery in New Haven. To plant Memorial Trees in memory of Daniel Rosner, please click here to visit our Sympathy Store.