Multiphase Flow and Thermal-hydraulics Laboratory


MFTL: Multiphase Flow and Thermal-hydraulics Lab

Yang Liu, Asst Professor, Mechanical Engineering

Department of Mechanical Engineering
635 Prices Fork Road
Blacksburg, VA 24061

Yang Liu

Assistant Professor

The laboratory performs experimental and computational studies on various multiphase flow and reactor thermal-hydraulics topics.  In the first area, we study the full spectrum of two-phase flow regimes that are of practical interest, ranging from bubble nucleation to film and droplet dynamics.  Research activities include advanced instrumentation development, experimental studies, and model development for both 1-D system codes and 3-D CFD codes.  In the area of reactor thermal-hydraulics, the focus is on reactor safety related issues.  Specific topics include air entrainment in the Emergency Core Cooling System, flow structure development in rod bundles, flow induced vibration on piping elements, passive safety systems, and spent fuel pool safety.

Current Students

Yucheng Fu, Ph.D. Student
BS, Mechanics and Engineering Science, Fudan University, 2013
Research Project
High resolution optical measurement of two-phase flow

Dewei Wang, Ph.D. Student
BS, Theoretics and Applied Mechanics, University of Science and Technology of China, 2013
Research Project
Development of advanced multi-sensor probes

Kyle Song, Ph.D. Student
BS, Mechanical Engineering, University of Virginia, 2013
Research Project
Development of a fast X-ray imaging system for two-phase flow measurement

Yuki Mugikura, M.S. Student
BS, Mechanical Engineering, Virginia Tech, 2014
Research Project
Advanced optical measurement of two-phase flow

Robert Langhans, M.S. Student
BS, Mechanical Engineering, Virginia Tech-Technische Universität Darmstadt, 2013
Research Project
CFD simulation of natural circulation and thermal stratification in a SFR plenum

Our Facility

Rectangular Two-phase Flow Loop

  • Fully transparent, 3 cm x1 cm rectangular test section, 3 m tall (z/dh=200)
  • Designed for air-water vertical upflows
  • Covering all two-phase flow regimes spanning from bubbly to annular flow
  • Two inlet configurations: bubbly flow injection and film flow injection
  • Three instrumentation stations (z/dh=8.8, 72.4 and 136) for conductivity probes, pressure transmitters and high speed cameras
  • A 10 hp multistage centrifugal pump with a maximum discharge head of 180 m
  • Two magnetic flow meters (±1% of the reading)
  • Four air mass flow meters (±1% of the reading)
  • One high precision dp transmitter
  • Complete data acquisition system

Circular Two-phase Flow Loop

  • 2.54 cm inner diameter, 3 m tall test section
  • Fully transparent, perfect for flow visualization and optical measurement
  • Share the same air and water delivery and measuring systems with the rectangular test loop
  • Specially designed two-phase injector using sintered metal tube
  • Three instrumentation stations along the axial direction

High Speed Imaging System

  • Two high speed cameras (Photron FASTCAM SA4 and SA6) owned by MFTL
  • Up to five high speed cameras (4 SA4s and 1 SA6) are available through collaboration
  • Attainable frame rate up to 500,000 fps (SA4)
  • Highest attainable resolution of SA6 is 1920 x 1440 at 1125 fps
  • Two 1500-unit LED panels, two 256-unit LED panels, and multiple halogen lights
  • Various lenses: 35 mm, 40 mm, 55 mm, 105 mm and 180 mm

X-Ray Two-Phase Flow Measurement System

A fast X-Ray two-phase flow imaging system is available at MFTL to perform void fraction and gas velocity measurement in various flow regimes ranging from bubbly to annular.

  • A compact X-ray source (50 KeV, 1 mA)
  • Two sets of specially designed line detector systems
  • Various pixel sizes ranging from 100~800 micrometer
  • Maximum line coverage up to 15 cm
  • Frame rate could exceed 1000 Hz
  • Void fraction, gas velocity, and gas flux can be measured by this system

Computational Resource

  • A dedicated 64-core AMD Opteron workstation
  • Several Dell Precision workstations based on Intel Xeon processors
  • Granted access to up to 1024 cores on the BlueRidge cluster managed by the Advanced Research Computing department at Virginia Tech

Laboratory address and students offices:

140 Kelly Hall
325 Stanger St.
Blacksburg, VA 24061-0477
Phone: 540-231-1442 (lab)

Department of Mechanical Engineering
College of Engineering, Virginia Tech
635 Prices Fork Road, Blacksburg, VA 24061