Skip to main content
SpringerLink
Log in

A new method for measuring time constants of a thermocouple wire in varying flow states

  • Originals
  • Published:
Experiments in Fluids Aims and scope Submit manuscript

Abstract

A new measuring method is suggested for determining the time constant of a thermocouple wire to be applied for the measurement of the true fluid temperatures in varying flow states. Based on the techniques of internal heating which are commonly used to measure mean time constants, we extend the existing method to measure instantaneous time constants continuously. A method of measurement and analysis is presented and verified experimentally.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Log in via an institution

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Similar content being viewed by others

Abbreviations

A s :

surface area [m2]

c :

specific heat [J/kg K]

D :

diameter [m]

h :

heat transfer coefficient [W/m2 K]

I :

current [A]

k :

thermal conductivity [W/m K]

L :

length [m]

r :

resistance per unit length [Ω/m]

T :

temperature [°C]

t :

time [s]

t c :

characteristic time to reach uniform state [s]

u :

velocity of stream [m/s]

V :

volume [m3]

x :

axial coordinate [m]

α:

thermal diffusivity [m2/s]

θ :

normalized temperature (≡TθT ∞)/(T RθT ∞))

ϱ :

density [kg/m3]

τ:

time constant [s]

ω :

angular velocity [rad/s]

a :

amplitude

i :

initial condition

j :

junction of thermocouple

R :

reference point

∞:

surrounding

References

  • Ballantyne A; Moss JB (1977) Fine wire thermocouple measurements of fluctuating temperature. Combust Sci Tech 17: 63–72

    Google Scholar 

  • Bradbury LJS; Castro IP (1971) A pulsed-wire technique for velocity measurements in highly turbulent flows. J Fluid Mech 49: 657–691

    Google Scholar 

  • Cambray P (1986) Measuring thermocouple time constants: A new method. Combust Sci Tech 45: 221–224

    Google Scholar 

  • Carslaw HS; Jaeger JC (1959) Conduction of heat in solids, 2nd ed., Chap. 2. London: Oxford University Press

    Google Scholar 

  • Collis DC; Williams NJ (1959) Two-dimensional convection from heated wires at low Reynolds numbers. J Fluid Mech 6: 357–384

    Google Scholar 

  • Katsuki M; Mizutani Y; Matsumoto Y (1987) An improved thermocouple technique for measurement of fluctuating temperatures in flames. Combust Flame 67: 27–36

    Google Scholar 

  • Lockwood FC; Moneib HA (1981) A new on-line pulsing technique for response measurements of thermocouple wires. Combust Sci. Tech 26: 177–181

    Google Scholar 

  • Mathioulakis E; Grignon M; Poloniecki JG (1994) A pulsed-wire technique for velocity and temperature measurements in natural convection flows. Exp Fluids 18: 82–86

    Google Scholar 

  • Ražnjevic' K (1987) Handbook of thermodynamic tables and charts. Washington DC: Hemisphere Publishing

    Google Scholar 

  • Talby R; Anselmet F; Fulachier L (1990) Temperature fluctuation measurements with fine thermocouples. Exp Fluids 9: 115–118

    Google Scholar 

  • Tanaka M; Yamashita I; Chisaka F (1990) Flow and heat transfer characteristics of the Stirling engine regenerator in an oscillating flow. JSME Int J II 33: 283–289

    Google Scholar 

  • Simon TW; Seume JR (1988) A survey of oscillating flow in Stirling engine heat exchangers. NASA CR-182108

Download references

Author information

Authors and Affiliations

  1. Department of Mechanical Engineering, Seoul National University, 151-742, Seoul, Korea

    S. J. Park & S. T. Ro

Authors
  1. S. J. Park
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. S. T. Ro
    View author publications

    You can also search for this author in PubMed Google Scholar

Additional information

The work was supported by Turbo and Power Machinery Research Center at Seoul National University and the authors are grateful to Mr. M. H. Yang for his assistance in the experiment.

Rights and permissions

Reprints and permissions

About this article

Cite this article

Park, S.J., Ro, S.T. A new method for measuring time constants of a thermocouple wire in varying flow states. Experiments in Fluids 21, 380–386 (1996). https://doi.org/10.1007/BF00189059

Download citation

  • Received:

  • Accepted:

  • Issue Date:

  • DOI: https://doi.org/10.1007/BF00189059

Keywords

Search

Navigation