       1. DATA No. (FILE NAME)
              N1000003

       2. KEY WORDS
              Natural Convection, Turbulent Boundary Layer, Reynolds
              Stress, Turbulent Heat Flux, Hot-Wire Measurement

       3. DATA TAKERS AND ARTICLE TITLE
           a. T. Tsuji?CY. Nagano, and M. Tagawa
           b. Dep. of Mech. Eng., Nagoya Institute of Technology
              Gokiso-cho, Showa-ku, Nagoya 466
           c. Structure and Heat Transport of a Turbulent Natural
              Convection Boundary Layer
           d. In preparation for the presentation at TSF 8

       4. ABSTRACT OF EXPERIMENT
                   Velocity and temperature measurements have been
              conducted to investigate the structure and heat transport
              of a turbulent natural convection boundary layer along a
              vertical plate.  The results presented include important
              knowledge of the spanwise velocity fluctuation, which is
              indispensable to the examination of the turbulent kinetic
              energy budget and the construction of a turbulence model
              for turbulent buoyant flows.  The turbulence structure is
              discussed on the basis of a spectral analysis of velocity
              and temperature fluctuations and a conditional sampling
              for Reynolds shear stress and turbulent heat fluxes.

       5. INSTRUMENTATION
                   The flat surface generating flow was a copper plate
              4 m high, 1 m wide and 2 mm thick.  Two V-shaped hot-wires
              in an X-array and a cold-wire were used to measure fluid
              velocity and temperature.  The V-shaped hot-wire was
              constructed by symmetrically bending a 0.0031 mm dia. and








              1.5 mm long tungsten wire at the center.  The cold-wire
              of 0.0031 mm dia. and 3.5 mm long tungsten wire located
              upstream of the hot-wires for temperature compensation.

       6. EXPERIMENTAL PARAMETERS
          *** Test conditions ***
                                    Comments
          x [m]        2.538      : Vertical location
          Tw[deg.]     60.00      : Wall temp.
          Ta[deg.]     18.60      : Ambient temp.
          Pa[Pa]      1.016E05    : Atom. pres.
          Grx         7.985E10    : Grashof no.
          Pr           0.710      : Prandtl no.

                   Physical properties were evaluated at the film
              temperature (=(Tw+Ta)/2), except that the body expansion
              coefficient B was defined as 1/Ta.  Ambient temperature
              increased at the rate of about 0.6 deg./m in the vertical
              direction.

       7. MEASURED VARIABLES
              T   - Mean temperature
              t2  - Intensity of temperature fluctuation (rms value)
              U   - Mean streamwise velocity
              u2  - Intensity of streamwise velocity fluctuation (rms value)
              ut  - Streamwise turbulent heat flux
              uw  - Reynolds stress
              W   - Mean spanwise velocity
              w2  - Intensity of spanwise velocity fluctuation (rms value)
              wt  - Spanwise turbulent heat flux
              y   - Distance normal to the flat plate

       8. DATA
          Grx=7.985E+10,  Tw=60.00 deg.,   Ta=18.60 deg.,  Pr=0.710
          u*=0.06801 m/s (u*: Friction velocity)
          t*=2.630 deg. (t*: Friction temperature)
          N=1.6881E-05 m**2/s (N: Kinematic viscosity)
          y+=u*y/N,  U+=U/u*,  V+=V/u*,  T+=(Tw-T)/t*

                   In evaluating u* and t*, the wall shear stress Fw
              and the wall heat flux were estimated from the following
              experimental formulas (ref. [1]):

                      Fw/(RUb**2)=0.684Grx**(1/11.9)
                      Nux=0.120(GrxPr)**(1/3)

              where Nux is the Nusselt number, R is the density and Ub is
              the reference velocity defined as [gB(Tw-Ta)N]**(1/3).


           a. Mean velocities and mean temperature

               y [mm]      y+           U+           W+           T+
            1    1.21    4.900E+00    3.669E+00   -3.000E-02    3.309E+00
            2    1.31    5.300E+00    4.022E+00   -3.500E-02    3.384E+00
            3    1.41    5.700E+00    4.204E+00   -3.300E-02    3.691E+00
            4    1.51    6.100E+00    4.489E+00   -4.000E-03    3.887E+00
            5    1.61    6.500E+00    4.727E+00   -2.000E-02    4.144E+00
            6    1.81    7.300E+00    5.155E+00    2.000E-02    4.675E+00
            7    2.01    8.100E+00    5.385E+00   -1.100E-02    5.089E+00
            8    2.21    8.900E+00    5.752E+00   -1.300E-02    5.499E+00
            9    2.41    9.700E+00    6.199E+00   -1.800E-02    5.820E+00
           10    2.61    1.050E+01    6.513E+00    1.600E-02    6.147E+00
           11    3.11    1.250E+01    7.108E+00    4.400E-02    7.165E+00
           12    3.61    1.450E+01    7.732E+00    3.700E-02    7.802E+00
           13    4.11    1.660E+01    8.035E+00    4.700E-02    8.545E+00
           14    4.61    1.860E+01    8.402E+00   -3.100E-02    8.842E+00
           15    5.61    2.260E+01    8.846E+00    1.000E-03    9.664E+00
           16    6.61    2.660E+01    9.268E+00    6.000E-03    1.021E+01
           17    7.61    3.070E+01    9.431E+00   -2.000E-03    1.060E+01
           18    8.61    3.470E+01    9.468E+00    1.300E-02    1.102E+01
           19    9.61    3.870E+01    9.485E+00    1.600E-02    1.132E+01
           20   10.61    4.280E+01    9.603E+00   -5.000E-03    1.147E+01
           21   13.61    5.480E+01    9.397E+00   -5.000E-03    1.212E+01
           22   16.61    6.690E+01    9.237E+00   -1.800E-02    1.241E+01
           23   20.61    8.300E+01    8.939E+00   -6.000E-03    1.285E+01
           24   25.61    1.032E+02    8.773E+00   -4.000E-03    1.312E+01
           25   30.61    1.233E+02    8.303E+00    4.400E-02    1.344E+01
           26   40.61    1.636E+02    7.741E+00    1.300E-02    1.377E+01
           27   50.61    2.039E+02    7.306E+00   -2.500E-02    1.406E+01
           28   60.61    2.442E+02    6.394E+00   -1.000E-02    1.435E+01
           29   70.61    2.845E+02    6.084E+00    2.100E-02    1.450E+01
           30   80.61    3.248E+02    5.424E+00    1.500E-02    1.467E+01
           31  100.61    4.053E+02    4.318E+00    1.100E-02    1.493E+01
           32  120.61    4.859E+02    3.389E+00   -2.200E-02    1.517E+01
           33  140.61    5.665E+02    2.438E+00   -5.000E-02    1.523E+01
           34  160.61    6.471E+02    1.925E+00   -4.800E-02    1.536E+01
           35  180.61    7.276E+02    1.510E+00   -3.600E-02    1.539E+01
           36  200.61    8.082E+02    1.258E+00    1.600E-02    1.537E+01


           b. Intensities of velocity and temperature fluctuations









               y [mm]      y+          u2/u*        w2/u*        t2/t*
            1    1.21    4.900E+00    7.420E-01    5.600E-01    1.451E+00
            2    1.31    5.300E+00    8.240E-01    5.810E-01    1.485E+00
            3    1.41    5.700E+00    8.900E-01    6.030E-01    1.580E+00
            4    1.51    6.100E+00    9.480E-01    6.990E-01    1.643E+00
            5    1.61    6.500E+00    1.009E+00    7.140E-01    1.768E+00
            6    1.81    7.300E+00    1.142E+00    7.840E-01    1.918E+00
            7    2.01    8.100E+00    1.245E+00    9.390E-01    2.082E+00
            8    2.21    8.900E+00    1.283E+00    1.018E+00    2.179E+00
            9    2.41    9.700E+00    1.342E+00    1.054E+00    2.283E+00
           10    2.61    1.050E+01    1.407E+00    1.110E+00    2.276E+00
           11    3.11    1.250E+01    1.487E+00    1.196E+00    2.450E+00
           12    3.61    1.450E+01    1.585E+00    1.285E+00    2.485E+00
           13    4.11    1.660E+01    1.669E+00    1.374E+00    2.555E+00
           14    4.61    1.860E+01    1.692E+00    1.471E+00    2.546E+00
           15    5.61    2.260E+01    1.770E+00    1.507E+00    2.527E+00
           16    6.61    2.660E+01    1.766E+00    1.504E+00    2.438E+00
           17    7.61    3.070E+01    1.756E+00    1.472E+00    2.350E+00
           18    8.61    3.470E+01    1.817E+00    1.511E+00    2.230E+00
           19    9.61    3.870E+01    1.832E+00    1.507E+00    2.157E+00
           20   10.61    4.280E+01    1.822E+00    1.528E+00    2.093E+00
           21   13.61    5.480E+01    1.878E+00    1.513E+00    1.876E+00
           22   16.61    6.690E+01    1.882E+00    1.521E+00    1.706E+00
           23   20.61    8.300E+01    1.942E+00    1.540E+00    1.527E+00
           24   25.61    1.032E+02    1.968E+00    1.568E+00    1.374E+00
           25   30.61    1.233E+02    1.987E+00    1.612E+00    1.205E+00
           26   40.61    1.636E+02    2.073E+00    1.637E+00    1.056E+00
           27   50.61    2.039E+02    2.005E+00    1.582E+00    8.970E-01
           28   60.61    2.442E+02    1.987E+00    1.557E+00    8.080E-01
           29   70.61    2.845E+02    1.981E+00    1.517E+00    7.160E-01
           30   80.61    3.248E+02    1.926E+00    1.450E+00    6.750E-01
           31  100.61    4.053E+02    1.759E+00    1.227E+00    5.640E-01
           32  120.61    4.859E+02    1.676E+00    9.440E-01    4.700E-01
           33  140.61    5.665E+02    1.368E+00    7.400E-01    4.610E-01
           34  160.61    6.471E+02    1.119E+00    6.430E-01    4.280E-01
           35  180.61    7.276E+02    8.810E-01    5.590E-01    4.290E-01
           36  200.61    8.082E+02    7.200E-01    5.040E-01    3.950E-01


           c. Reynolds stress and turbulent heat fluxes

               y [mm]      y+         uw/u*u*      ut/u*t*      wt/u*t*
            1    1.21    4.900E+00   -1.800E-02    8.000E-03    6.400E-02
            2    1.31    5.300E+00    1.000E-03   -9.600E-02    5.200E-02
            3    1.41    5.700E+00   -4.000E-03   -4.300E-02    5.200E-02
            4    1.51    6.100E+00    5.000E-03   -7.600E-02    6.500E-02
            5    1.61    6.500E+00   -2.000E-03   -1.750E-01    2.500E-02
            6    1.81    7.300E+00    8.000E-03   -5.000E-02    2.600E-02
            7    2.01    8.100E+00    6.400E-02   -4.100E-02   -4.100E-02
            8    2.21    8.900E+00    6.000E-02   -2.400E-02    3.300E-02
            9    2.41    9.700E+00    8.400E-02   -2.800E-02    5.000E-02
           10    2.61    1.050E+01    5.400E-02    0.000E+00    8.700E-02
           11    3.11    1.250E+01    2.100E-02    3.360E-01    1.000E-03
           12    3.61    1.450E+01    3.000E-02    5.830E-01    7.600E-02
           13    4.11    1.660E+01   -4.000E-03    9.780E-01    3.200E-02
           14    4.61    1.860E+01    4.000E-02    1.087E+00    4.500E-02
           15    5.61    2.260E+01    3.500E-02    1.557E+00    4.000E-03
           16    6.61    2.660E+01   -3.200E-02    1.618E+00    4.700E-02
           17    7.61    3.070E+01    3.100E-02    1.751E+00    8.700E-02
           18    8.61    3.470E+01    3.500E-02    1.971E+00    2.500E-02
           19    9.61    3.870E+01    3.600E-02    1.981E+00   -1.500E-02
           20   10.61    4.280E+01    2.000E-02    1.972E+00   -6.000E-03
           21   13.61    5.480E+01    8.000E-02    2.012E+00   -8.000E-02
           22   16.61    6.690E+01    6.100E-02    1.849E+00    7.500E-02
           23   20.61    8.300E+01    1.000E-02    1.816E+00    4.000E-03
           24   25.61    1.032E+02    6.000E-02    1.663E+00    1.600E-02
           25   30.61    1.233E+02   -4.900E-02    1.426E+00   -2.000E-02
           26   40.61    1.636E+02    2.900E-02    1.323E+00   -8.000E-03
           27   50.61    2.039E+02    1.300E-02    1.075E+00   -3.100E-02
           28   60.61    2.442E+02    2.600E-02    9.280E-01    1.000E-03
           29   70.61    2.845E+02    0.000E+00    8.190E-01   -6.000E-03
           30   80.61    3.248E+02   -1.200E-02    7.360E-01   -1.600E-02
           31  100.61    4.053E+02   -1.900E-02    5.060E-01    1.400E-02
           32  120.61    4.859E+02    2.900E-02    4.130E-01   -7.000E-03
           33  140.61    5.665E+02    4.100E-02    2.250E-01    9.000E-03
           34  160.61    6.471E+02    6.200E-02    1.370E-01    1.300E-02
           35  180.61    7.276E+02    1.600E-02    4.200E-02    1.000E-02
           36  200.61    8.082E+02   -4.900E-02   -5.000E-03   -2.000E-03


       9. MEASUREMENT UNCERTAINTY
                   The estimated uncertainties (95% coverage) at y =9.61 mm
              are as follows:

                      y+     = ?}0.13
                      U+     = ?}0.14
                      W+     = ?}0.24
                      T+     = ?}0.13
                      u2/u*  = ?}0.04
                      w2/u*  = ?}0.03
                      t2/t*  = ?}0.05








                      uw/u*u*= ?}0.08
                      ut/u*t*= ?}0.07
                      wt/u*t*= ?}0.05

      10. REFERENCE
           1. T. Tsuji and Y. Nagano, Characteristics of a Turblent Natural
              Convection Boundary Layer along a Vertical Flat Plate, Int.
              J. Heat Mass Transfer 31, 1723-1734 (1988).

      11. GRAPH
