Obituary: Professor Chia-Shun Yih
Chia-Shun Yih, Stephen P. Timoshenko Distinguished University Professor Emeritus at the University of Michigan, internationally known in his field, fluid mechanics, died April 25 outside of Tokyo at the age of 78. He was on a flight from Detroit to Taiwan to attend scientific meetings, when he died quietly in his sleep of acute heart failure.
He was a member of the Department of Mechanical Engineering and Applied Mechanics. His numerous honors included a Guggenheim Fellowship (1964), the Alexander von Humboldt Senior Scientist Award (Germany, 1977-78), the Theodore von Karman Medal (American Society of Civil Engineers, 1981), the Stephan S. Attwood Award (University of Michigan, 1984), the Fluid Dynamics Prize (American Physical Society, 1985), and the Otto Laporte Award (APS, 1989). He was elected to the American Physical Society (1958), the National Academy of Engineering (1970), and the Academia Sinica (the Chinese National Academy of Science in Taiwan). Prof. Yih was one of three scientists who, at the 1996 meeting of the Academia Sinica, proposed the creation of an institute of mechanics in Taiwan. He was enroute to a meeting to discuss the status of mechanics in Taiwan and the mission of such an institute when he died.
Prof. Yih was born in 1918 in Kweiyang, Kweichow Province, China. He entered Soochow Middle School in 1934, where his eagerness to learn led him to travel to Shanghai one spring vacation on a book-buying expedition. He returned with books on mathematics, physics, and chemistry, as well as numerous works of English and American literature, all in English.
It was a difficult period in China’s history. Japan had occupied Manchuria since 1931 and threatened further expansion into China. "Full-scale war between China and Japan finally broke out in 1937, soon after our graduation from high school," recalls Yih’s former classmate and life-long friend, Prof. Yuan-Cheng Fung. "We managed to take the entrance examination of the National Central University, in Nanking, about two months before its fall. Our university was moved to Chungking, far in the hinterland . . . Our college years were spent in makeshift classrooms and laboratories, classes at the crack of dawn to avoid air raids, long hours in the dugouts, military training, and an endless stream of exciting or sad news." Prof. Yih proudly recalled rising in the pre-dawn hours to study by candlelight.
After graduating in 1942, Yih worked at the National Hydraulic Laboratory, the National Bureau of Bridge Design, and the National University of Kweichow. "At that stage we both intended to be practicing engineers," writes Fung. "Then something changed our lives. By nationwide examinations, the Ministry of Education chose 42 scholars to study in the United States. We were among the 42, and after the war, came to the U.S. via India." From Calcutta they traveled through the Suez Canal and across the Atlantic on an American troop ship, landing in New York City on December 28, 1945. Yih’s first purchases in the U.S. were a Webster’s dictionary and a ticket to hear the famed contralto, Marian Anderson.
Entering the University of Iowa in 1946, Yih rapidly completed his graduate work in the Department of Mechanics and Hydraulics, earning his M.S. in 1947 and Ph.D. in 1948. In 1949, he and Shirley Ashman were married, and he taught at universities in North America and France before coming to the University of Michigan as an associate professor, in 1956. Two years later, he was promoted to professor of Fluid Mechanics. In 1967 he was named Stephen P. Timoshenko Distinguished University Professor, and in 1974 he was chosen to give the Henry Russel Lecture -- the highest honor the University of Michigan can bestow upon a senior faculty member.
His published work includes well over 100 scientific papers as well as two books, Dynamics of Nonhomogeneous Fluids (1960), later revised as Stratified Flows (1980), and Fluid Mechanics, A Concise Introduction to the Theory (1969). One colleague noted that "his depth of achievement in the broad areas of mechanics and applied mathematics is matched by his abilities in the physical sciences generally . . . he could logically be a professor in mathematics or physics or in any one of several engineering departments."
In a 1977 letter to a friend, Yih wrote, "For me, the criterion of science is truth, but its motivation resides in a sense of beauty -- and in that it is like art." He delighted in the beauty of nature and took a lively interest in the arts, including Chinese and Western literature and painting. He was particularly drawn to the French Impressionists. During a sabbatical in Geneva, Switzerland in 1964, he took up painting, going frequently into the mountains with easel and paintbox. He produced scores of canvases in the ensuing years. He was a keen enthusiast of gardens and had planted five flowering trees at his home in Ann Arbor a week before his death. "Given another lifetime," wrote a colleague, "one feels he might prefer to be a painter or a poet; but in his present incarnation, he is outstanding as an applied mathematician."
His students found him an inspiring teacher whose excitement and enthusiasm were contagious, and he was much in demand as a doctoral thesis adviser. He is remembered for his quick mind, spontaneity, enthusiasm, and love of life.
Prof. Yih is survived by his wife Shirley; sisters Chia-Ju and Chia-Ling; children Yiu-Yo, David, and Katherine; and three grandchildren. A memorial ceremony will be held in Ann Arbor in July.
The poet Donald Hall once persuaded Yih to write about life in China. "Old China Remembered" appeared in The Ohio Review in 1977. Hall wrote in his introduction to this series of vignettes: "When I think of Chia-Shun now in his absence, he smiles with a wild enthusiasm -- and it may be enthusiasm over a poem a thousand years old, or over a problem he is solving . . ., or over the petal of a flower in front of us. He delights in the world . . . but unlike most humans -- scientist or poet or salesman or factory worker -- his world moves far outside the borders of his work; it is wide with things to be loved and cherished."