John H. Lienhard V
John Henry Lienhard V (born 1961) is the Abdul Latif Jameel Professor of Water and Mechanical Engineering at the Massachusetts Institute of Technology. His research focuses on desalination, heat transfer, and thermodynamics. He has also written several engineering textbooks. Childhood and education Lienhard was born in 1961 in Pullman, Washington, where his father, John H. Lienhard IV, was a professor at Washington State University. His mother, Carol Ann Bratton, a violinist, was a member of the Washington State University String Quartet. The family moved to Lexington, Kentucky in 1967 when his father took a position at the University of Kentucky. Lienhard attended primary school and high school in Lexington. Lienhard enrolled at the University of Kentucky when he was 16. He completed his bachelor's degree in engineering, summa cum laude, at the University of California, Los Angeles in 1982, and he took his master's degree in heat and mass transfer at UCLA in 1984 for research on Rayleigh–Bénard instability. He then transferred to the University of California, San Diego, where he wrote his doctoral dissertation on wind tunnel measurements of strongly stratified turbulent flow, finishing in 1988. Lienhard's doctoral experiments encompassed Brunt–Väisälä frequencies up to 2.4 s−1 and required the development of hot-wire anemometry usable in the presence of large temperature fluctuations. Career Lienhard joined the mechanical engineering faculty of the Massachusetts Institute of Technology in 1988, immediately after graduating from UCSD. He has spent his entire professional career at MIT. Lienhard's initial research at MIT focused on cooling by liquid jet impingement. This work included fundamental convection problems, droplet splattering, free-surface turbulence interactions, and pattern-formation in the hydraulic jump. The thin boundary layer at a jet's stagnation point also provided an attractive avenue to high heat flux engineering. In 1993, Lienhard's group reported the highest steady state fluxes to that date removed from a macroscopic area, achieved using a high speed water jet (≈40 kW/cm2). They later extended this approach to arrays of jets, allowing larger areas to be cooled at high flux. In 1998, they used a water jet array at 46 m/s to remove 1.7 kW/cm2 by convection alone over areas of several cm2. In the 2000s, Lienhard refocused his research on the problem of clean water supply and scarcity, particularly around desalination technologies. He approached this area through his background in thermal engineering and transport phenomena, making energy efficiency a central aim. His group's desalination research has spanned a broad range of topics including humidification-dehumidification, forward and reverse osmosis, membrane distillation, produced water, electrodialysis, nanofiltration, solar desalination, and thermophysical properties. The seawater thermophysical property database developed by his group has been widely used by other researchers. Lienhard has written hundreds of peer-reviewed research publications and has been issued more than 35 US patents. The patents have facilitated several start-up companies formed by his former students. Lienhard has been responsible for launching a number of major research programs at MIT. He was the founding director of the Center for Clean Water and Clean Energy (2008–2017), a multi-million