In this review paper, we will do some compilation
between some typical fluid measurement did by some researcher on fluid type
dynamic. In this discuss in some detail how they used in depended coefficient to find the other
coefficient and see what is the changed, and compared with previous study.
Using the application lows like Newton’s second law (F _ ma) or Bernoulli
equation as it is applied to fluid. It can be used to find the relationship
between the coefficients. However can provide a good foundation for the comparing
of the data between the researchers.
The last measurements did by 1. SO he try to
fine velocity profiles in fully developed turbulent pipe flow are also using a
smaller Pitot probe to decline the uncertainties due to velocity gradient
corrections. The other researcher, use the pressure correction (McKeon &
Smits 2002) 3 frome his analyzing the data this data leads to important
differences from the (Zagarola & Smits) (ZS) 4 conclusions. The results confirm
the being there of a power-law region near to the wall also, for Reynolds
numbers greater than 230×103 (R+ >5×103),
a logarithmic region further out, but the limits of these regions
and some of the constants change from those reported by (Zagarola & Smits).
In special, the log law is found for
600< y+ < 0.12 R+ (as an alternative of 600 < y+ < 0.07R+), and the von Karman constant ?, the additive constant B for the log law using for internal flow scaling, and the additive constant B ? for the log law using outer scaling are appeared to be ( 0.421 ± 0.002, 5.60 ± 0.08 and 1.20 ± 0.1) , respectively, by 95% confidence level (compared by ( 0.436 ± 0.002, 6.15 ± 0.08, and 1.51 ± 0.03) analyzed by ZS). Furthermore , the new results confirm the illustrated by ZS that their pipe flow data are not affected by surface roughness until the highest Reynolds numbers (ReD >13.6×106,
at a minimum).
For region 350 < y+ < 950, the statistics could be assumed to be in reason of good union by the findings with (Osterlund et al) 4, that is recommend a log law by ? =0.38 and B =4.1 for 200 < y+ < 0.15R+ for turbulent boundary layers. The values of ? and B measured by ( Osterlund et al). are clearly different, nevertheless, from the values given here for the region of totaly similarity which occurs more from the wall, that is do for 600 < y+ < 0.12R+, and the power and log law scale given in this paper represent the data more absolutely.