Amitabh Narain

Professor

Ph.D., University of Minnesota

Fluid Mechanics and Heat Transfer

Contact Email: narain@mtu.edu

Publications

Curriculum Vitae

Research Interests

 

                        Narain’s current research interests are both computational and experimental in nature and emphasize the area of free-surface flows – especially internal condensing flows.  His secondary interests are in related areas of transport processes. These include cavitation signatures in an automobile’s torque-converter, computational simulations of forced and natural convection turbulent flows through heat exchangers, displacement pumps, etc.  The condensing flow research has demonstrated the significance of exit conditions on condenser operations. The experiments demonstrate how exit-condition effects can lead to different steady flows as well as unsteady/oscillatory flows that result from system-instabilities. The results relate to effective design and operation of applications (from micro- to macro- scales) that employ condensers. These applications could be ground and space based thermal management systems (e.g. looped heat pipes, etc.), Rankine power cycles, etc.

                        Ongoing condensing flow research has achieved significant milestones. These are: state of the art computational code capable of simulating these flows including the time-varying locations of the wavy interface, development of a new state of the art experimental facility for investigating internal condensing flows, and our own invention of a well tested fluorescence and fiber-optic based film thickness sensor capable of measuring time-varying thicknesses of a dynamic film. Recent publications discuss results obtained from accurate direct computational simulations and experiments for two dimensional internal condensing flows - both in steady and unsteady (i.e. wavy-interface) regimes. The simulations and experiments (funded by NSF and NASA) identify various instability mechanisms and flow regimes/categories. For condensation inside vertical tubes and channels, the ongoing experiments employ modern electronic flow control techniques, fiber-optic flow visualization techniques, our own fluorescence and fiber-optic based sensor for measuring local time varying thickness of the liquid film, etc.