The single-largest gift in University of Denver history — nearly $27 million from former chancellor and Board of Trustees chairman Daniel Ritchie — will help fund a new center for the study of aging as well as a school for engineering and computer science.

Other donors contributing to the total gift of $41 million are Betty Knoebel, widow of Denver food-service pioneer Ferdinand "Fritz" Knoebel, and the estate of the late William C. Petersen, an alumnus of the DU School of Engineering who had a lengthy career at the Gates Rubber Co. in Denver.

Construction on the new 110,000-square-foot facility, which will house the Daniel Felix Ritchie School of Engineering and Computer Science and the Knoebel Center for the Study of Aging, is expected to begin this fall, with the building opening in 18-24 months.

"This is an extraordinarily exciting time for our university, and these gifts will go a long way in transforming and redefining the focus of our science, engineering and related programs and research," DU chancellor Robert Coombe said. "It will help us lay a strong foundation for collaboration across disciplines, while we expand our ability to serve the future needs of our region and state."

Knoebel's gift amounts to $9.2 million and comes from the proceeds of the sale of a ranch that she donated to the school in 2010. Petersen's gift is for $4.8 million.

The Knoebel Center for the Study of Aging will focus on research that addresses aging and aging-related conditions. It will be focused on biomedical and social sciences research and discovery, with the intent of increasing the healthy years of life.

The center's lab will occupy a floor in the Daniel Felix Ritchie School of Engineering and Computer Science. The facility will serve as the centerpiece for what the university says is an effort to expand interdisciplinary science, technology, engineering and mathematics offerings.

The building, to be named in honor of Ritchie's father, will be located on the southern part of campus, between the Newman Center for the Performing Arts and Olin Hall.