Josiah D. Knight

Research Themes

Energy Systems & Materials

Research Interests

Fluid mechanics, thermodynamics, heat transfer, and dynamics

Bio

Josiah Knight, Associate Professor of Mechanical Engineering, is Co-Director of the Energy and Environment Certificate, a program that prepares students to confront complex problems in providing safe, clean, reliable and affordable energy. The curriculum brings together students from arts and sciences as well as engineering in a series of courses spanning natural science, social science and technology, culminating in a capstone course in which multidisciplinary teams design, build, test and evaluate energy system prototypes. In the process, students learn to communicate across a spectrum of backgrounds and interests, as they must do to address energy problems in the larger world.

Knight's current research interests are in solar thermal energy and alternate propulsion methods for ground transportation. Solar thermal energy, in addition to direct uses for space, water and industrial heating, has been shown to be an efficient means of electricity generation. Much progress has been made in recent years on fault-tolerant solar thermal collectors, and integration of such systems with distributed power generation is a promising path toward low-carbon electricity.

Alternatives to the gasoline and diesel internal combustion engine have potential to expand the range of fuels that can be efficiently used for transportation and stationary power. A major issue in the development of biofuels for ICEs is that much of the heating value of the biomass is consumed in transforming the solids to liquid fuels. Burning solid biomass directly delivers greater net energy, but must be done in external combustion. Activity in this area is presently focused on optimizing performance of external combustion engines by using adaptive intake and exhaust porting and closed-loop valve control. The area is rich in both applied and basic questions that couple thermodynamics and electro-mechanical dynamics in nonlinear regimes.

Education

• B.S. University of Virginia, 1980
• M.S. University of Virginia, 1982
• Ph.D. University of Virginia, 1986

Positions

• Associate Professor of the Thomas Lord Department of Mechanical Engineering and Materials Science
• Director of Energy Engineering Education

Awards, Honors, and Distinctions

• P.M. Ku Award. Society of Tribologists and Lubrication Engineers. 2005

Courses Taught

• ME 592: Research Independent Study in Mechanical Engineering or Material Science
• ME 591: Research Independent Study in Mechanical Engineering or Material Science
• ME 555: Advanced Topics in Mechanical Engineering
• ME 492: Special Projects in Mechanical Engineering
• ME 490: Special Topics in Mechanical Engineering
• ME 461: Energy Engineering and the Environment
• ME 331L: Thermodynamics
• ENRGYEGR 310: Introduction to Energy Generation, Delivery, Conversion and Efficiency
• ENERGY 796T: Bass Connections Energy & Environment Research Team
• ENERGY 795-1: Connections in Energy: Interdisciplinary Team Projects
• ENERGY 396T: Bass Connections Energy & Environment Research Team
• ENERGY 395-1: Connections in Energy: Interdisciplinary Team Projects
• ENERGY 310: Introduction to Energy Generation, Delivery, Conversion and Efficiency
• EGR 424L: Energy and Environment Design

Publications

• Plaut RH, Virgin LN, Knight JD. Predicting critical speeds in various rotordynamics problems. Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science. 2017 Nov 1;231(21):3913–22.
• Knight JD, Virgin LN, Plaut RH. Predicting Critical Speeds in Rotordynamics: A New Method. In: Journal of Physics: Conference Series. 2016.
• Virgin LN, Knight JD, Plaut RH. A New Method for Predicting Critical Speeds in Rotordynamics. Journal of Engineering for Gas Turbines and Power. 2016 Feb 1;138(2).
• Richter DD, Jenkins DH, Karakash JT, Knight J, McCreery LR, Nemestothy KP. Resource policy. Wood energy in America. Science (New York, NY). 2009 Mar;323(5920):1432–3.
• Richter DDBJ, Jenkins DH, Karakash JT, Knight J, Mccreery LR, Nemestothy KP. Wood Energy: The Dangers of Combustion Response. SCIENCE. 2009;324(5933):1390–1.
• Knight J. Welcome from the technical program chair. Proceedings of the ASME/STLE International Joint Tribology Conference, IJTC 2004. 2004 Dec 1;(PART B).
• Knight JD. Strategic plan guides STLE toward future success - New mission statement is first step. LUBRICATION ENGINEERING. 2002 Apr 1;58(4):5-+.
• Knight JD, Ghadimi P. Analysis and observation of cavities in a journal bearing considering flow continuity. Tribology Transactions. 2001;44(1):88–96.
• Ecker H, Knight JD, Wu L. Nonlinear dynamic simulation of an active magnetic bearing system with non-symmetric coordinate coupling forces. In: American Society of Mechanical Engineers (Paper). 1997.
• Ecker H, Knight JD, Wu L. Nonlinear dynamic simulation of an active magnetic bearing system with non-symmetric coordinate coupling forces. Proceedings of the ASME Turbo Expo. 1997 Jan 1;4.
• Virgin LN, Walsh TF, Knight JD. Nonlinear behavior of a magnetic bearing system. Trans ASME, J Eng Gas Turbines Power (USA). 1995;117(3):582–8.
• Virgin LN, Walsh TF, Knight JD. Nonlinear behavior of a magnetic bearing system. American Society of Mechanical Engineers (Paper). 1994 Jan 1;1–7.
• Virgin LN, Walsh TF, Knight JD. Nonlinear behavior of a magnetic bearing system. Proceedings of the ASME Turbo Expo. 1994 Jan 1;5.
• Sato Y, Knight JD. Closure to “Discussions of ‘Performance Characteristics of Shrouded Rayleigh-Step and Spiral Groove Viscous Pumps’” (1992, ASME J. Tribol., 114, pp. 504–505). Journal of Tribology. 1992 Jul 1;114(3):505–6.
• Knight JD, Xia Z, McCaul E, Hacker HJ. Determination of forces in a magnetic bearing actuator: Numerical computation with comparison to experiment computation with comparison to experiment. Journal of Tribology, Transactions of the ASME. 1992;114(4):796–801.
• Sato Y, Knight JD. Performance characteristics of shrouded Rayleigh-step and spiral groove viscous pumps. Journal of Tribology, Transactions of the ASME. 1992;114(3):499–506.
• Knight JD, Ghadimi P. Effects of modified effective length models of the rupture zone on the analysis of a fluid journal bearing. Tribology Transactions. 1992 Jan 1;35(1):29–36.
• Sato Y, Knight JD, Somerday B. Observation and prediction of cavities in a lubricant between non-parallel disks in relative rotation. Tribology Transactions. 1992 Jan 1;35(1):170–6.
• Sato Y, Knight JD. Performance characteristics of shrouded Rayleigh-step and spiral groove viscous pumps. American Society of Mechanical Engineers (Paper). 1991 Dec 1;1–5.
• Knight JD, Niewiarowski AJ. Effects of two film rupture models on the thermal analysis of a journal bearing. Journal of Tribology, Transactions of the ASME. 1990;112(2):183–8.
• Knight JD. Prediction of temperatures in tilting pad journal bearings. Tribology Transactions. 1990 Jan 1;33(2):185–91.
• Knight JD, Niewiarowski AJ. Effects of two film rupture models on the thermal analysis of a journal bearing. American Society of Mechanical Engineers (Paper). 1989 Dec 1;
• Zuck CJ, Flack RD, Knight JD. Experiments and stability predictions of two sets of tilting pad bearings on an overhung rotor. STLE TRIBOLOGY TRANS. 1988;31(4, Oct. 1988):468–75.
• Knight JD, Barrett LE. ANALYSIS OF TILTING PAD JOURNAL BEARINGS WITH HEAT TRANSFER EFFECTS. Journal of Tribology, Transactions of the ASME. 1988;110(1):128–33.
• Zuck CJ, Flack RD, Knight JD, Barrett LE. Experiments and stability predictions of two sets of tilting pad bearings on an overhung rotor. Tribology Transactions. 1988 Jan 1;31(4):468–75.
• Knight JD. Analysis of axially grooved journal bearings with heat transfer effects. ASLE Transactions. 1987 Jan 1;30(3):316–23.
• Knight JD, Barrett LE. Analysis of tilting pad journal bearings with heat transfer effects. 1987 Jan 1;
• Knight JD, Barrett LE. ANALYSIS OF AXIALLY GROOVED JOURNAL BEARINGS WITH HEAT TRANSFER EFFECTS. ASLE Transactions. 1987;30(3):316–23.
• Knight JD, Barrett LE. Analysis of tilting pad journal bearings with heat transfer effects. 1987 Jan 1;
• Knight JD, Barrett LE. ANALYSIS OF AXIALLY GROOVED JOURNAL BEARINGS WITH HEAT TRANSFER EFFECTS. ASLE Preprints. 1986 Dec 1;
• Knight JD, Barrett LE, Cronan RD. The effects of supply pressure on the operating characteristics of two-axial-groove journal bearings. ASLE Transactions. 1985 Jan 1;28(3):336–42.
• Allaire PE, Barrett LE, Flack RD, Barton FW, Knight JD. ROTOR DYNAMIC ANALYSIS OF A NUCLEAR HEAT TRANSPORT PUMP UNDER NORMAL AND PART VOID CONDITIONS. I Mech E Conference Publications (Institution of Mechanical Engineers). 1984 Dec 1;23–30.
• Allaire PE, Barrett LE, Flack RD, Barton FW, Knight JD. Rotor dynamic analysis of nuclear heat transport pump under normal and part void conditions. 1984 Jan 1;
• Allaire PE, Barrett LE, Flack RD, Barton FW, Knight JD. Rotor dynamic analysis of nuclear heat transport pump under normal and part void conditions. 1984 Jan 1;
• Knight JD, Barrett LE. An approximate solution technique for multilobe journal bearings including thermal effects, with comparison to experiment. ASLE Transactions. 1983 Jan 1;26(4):501–8.
• Allaire PE, Lewis DW, Knight JD. Active Vibration Control of a Single Mass Rotor on Flexible Supports. Journal of the Franklin Institute. 1983 Jan 1;315(3):211–22.
• Knight JD, Barrett LE. APPROXIMATE SOLUTION TECHNIQUE FOR MULTILOBE JOURNAL BEARINGS INCLUDING THERMAL EFFECTS, WITH COMPARISON TO EXPERIMENT. ASLE Preprints. 1982 Dec 1;