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Measurements of Local Instantaneous Convective Heat Transfer in a Pipe - Single and Two-phase Flow
Published on: April 30, 2018
Temperature measurement in laminar free convective flow using digital holography
Md Mosarraf Hossain1, Chandra Shakher
1Laser Applications and Holography Laboratory, Instrument Design Development Center, Indian Institute of Technology, Delhi, New Delhi-110016, India.
Applied Optics
|April 3, 2009
Summary
A new digital holographic interferometry method accurately measures water temperature during laminar free convection. This fast, simple technique avoids complex phase shifting, offering precise temperature determination for fluid dynamics research.
Area of Science:
- Fluid Dynamics
- Optical Metrology
- Thermodynamics
Background:
- Accurate temperature measurement is crucial for understanding fluid dynamics, particularly in free convection flows.
- Traditional methods can be complex, time-consuming, or require specialized equipment.
- Digital holographic interferometry offers a promising non-intrusive approach for quantitative flow analysis.
Purpose of the Study:
- To present a novel, simplified method for measuring temperature in laminar free convection water flow.
- To validate the accuracy of the proposed method using established principles.
- To demonstrate the applicability of the technique for fluid temperature characterization.
Main Methods:
- Utilized lensless Fourier transform digital holography for hologram recording and reconstruction.
- Employed a quantitative phase analysis of two digital holograms: one in a quiescent state and one during convection.
- Applied the Tilton and Taylor equation to correlate refractive index changes with temperature.
Main Results:
- Successfully measured quantitative temperature variations in laminar free convection flow.
- Demonstrated a simple and fast experimental procedure without phase-shifting requirements.
- Visualized turbulent free convection flow patterns, showcasing the method's versatility.
Conclusions:
- The presented digital holographic interferometry method provides a simple, fast, and accurate means for temperature measurement in laminar free convection.
- The technique effectively leverages refractive index changes to determine fluid temperature.
- This approach has significant potential for advanced fluid dynamics and heat transfer studies.
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