James P. Johnston

Professor Emeritus
Faculty of Thermosciences Division, Department of Mechanical Engineering

Phone: 650-723-4024 | Fax: 650-723-4548 | Email: jpj@stanford.edu

Degrees: Mechanical Engineering
At the Massachusetts Institute of Technology:
B.S. & M.S. (1954), Sc.D. (1957).

Short Resume

He was Chairman of the Thermosciences Division, 1985/90, and Associate Chairman of the Mechanical Engineering Department, 1992/94. Before joining the faculty of the Mechanical Engineering Dept. of Stanford University in 1961, he worked at Ingersoll-Rand Company as a research engineer (1957/61).  He became emeritus in 1994.  Research and teaching covered many areas of fluid dynamics, gas dynamics, and thermodynamics with a particular emphasis on areas where basic knowledge had important impact on the performance of flow machinery (turbines, compressors, pumps, diffusers, nozzles, etc.).  Twenty-five graduate students earned their Ph.D. degrees under his supervision.

He received a Freeman Fellowship from the ASME (1967), the ASME's Robert T. Knapp research paper award (1975), an AIAA Survey Paper citation (1981), and he was elected as a Fellow of ASME in 1984. He has served as Associate Editor of the Journal of Fluids Engineering. He is currently a life member of ASME. He is the author of over 90 published papers, several book chapters and many conference papers and reports.

Recent Publications

J.P. Johnston and K.A. Flack, "Advances in Three-Dimensional Turbulent Boundary Layers with Emphasis on the Wall-Layer Regions," J. Fluids Engr., Vol. 118, No. 2, 219-233, (1996).

M.W. Plesniak, R.D. Metha, and J.P. Johnston, "Curved Two-Stream Mixing Layers Revisited," Experimental Thermal and Fluid Science, Vol. 13, No. 3, 190-205, (1996).

J.P. Johnston, "Effects of system rotation on turbulence structure - A Review Relevant to Turbomachinery Flows," International Journal of Rotating Machinery, Vol. 4, No. 2, pp. 97-112 (1998).

K.A. Flack and J.P. Johnston, "Near-Wall flow in a Three-Dimensional Boundary layer on the Endwall of a 30 deg. Bend," Experiments in Fluids, Vol. 24, pp. 175-184 (1998).

J.P. Johnston, "Diffuser Design and Performance Analysis by a Unified Integral Method," Trans. ASME, J. Fluids Engr., Vol. 120, No. 1, pp. 6-18, (1998).

J.P. Johnston, "Pitched and Skewed Vortex Generator Jets for Control of Turbulent Boundary Layer Separation: a Review," A keynote paper for 3rd ASME/JSME Joint Fluids Engineering Conference and FED Summer Meeting, San Francisco, July 18-22, (1999).

Z.U. Khan and J.P. Johnston, "On Vortex Generating Jets," International J. of Heat and Fluid Flow, Vol. 21, No. 5, pp. 505-511, (2000).

J.P. Johnston, B.P. Mosier, and Z.U. Khan, "Vortex generating jets, effects of jet-hole inlet geometry," International J. of Heat and Fluid Flow, Vol. 23, No. 6, pp. 750-757 (2002).

S. Kang, J.P. Johnston, T. Arima, M. Matsunaga, H. Tsuru, and F.B. Prinz, "Micro-scale Radial-Flow Compressor Impeller Made of Silicon Nitride - Manufacturing and Performance," Trans. ASME, J. of Gas Turbines and Power, Vol. 126, No. 2, pp. 358-365, (2004)

J.P. Johnston, S. Kang,, T. Arima, M. Matsunaga, H. Tsuru, and F.B. Prinz, "Performance of a micro-scale radial-flow compressor made of silicon nitride," Paper No: IGTC03 XXX-094, International Gas Turbine Congress, November 2-7, Tokyo, Japan, (2003).  

Primary Interests

1. Turbulent boundary layer separation, reattachment, and control of stall.  Control of flow separation and stall by active and passive means for internal flows, e.g. diffusers. Recent work concentrated on use of Vortex Generator Jets, the VGJ method, for active generation of longitudinal vortices as replacements for solid vortex generators for separation control.

2. Flow in, performance of, and the design of Diffusers. The prediction of subsonic flow in diffusers has advanced in recent years, but a method developed in the late 1970's and early 80's, the Unified Integral Method, still appears to be useful for rapid estimation of diffuser performance. This method is reviewed in our 1998 J. of fluids Engineering paper.  

3. Micro-scale gas turbine power generator. From 1999 through 2002, a very small gas turbine engine/generator with design output of 100 Watts was under development by the Stanford Rapid Prototyping Laboratory directed by Prof. F.B. Prinz. We assisted to his group in regards the gas dynamics and fluid dynamics in the turbomachinery.  A high-speed, radial-flow compressor, radial-turbine and shaft assembly (12 mm rotor diameter) was manufactured as a single component from Silicon Nitride, a material chosen to withstand temperatures as high as 1300 degrees C.  Aerodynamic performance experiments at reduced speed (420,000 rpm) and CFD at design speed (800,000 rpm) for the compressor impeller showed that it should meet design requirements (Pr = 3 and efficiency of 65% at design point flow rate of 2.4 g/sec). 

For further information, e-mail jpj@stanford.edu

tsd@www-tsd.stanford.edu

Last updated May 5, 2004.

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