Question

a. 1) Each of the following statements about Buckingham Pi Theorem is true, EXCEPT, An equation of variables can be reduced to a function of A- Pis where requals the number of dimensions involved. b. An equation of variables can be reduced to a function of Pis where requals the number of basic dimensions involved e. The theorem applies to either the MLT or the FLT dimension system d. The theorem is based on dimensional homogeneity of an equation that describes a meaningful physical phenomenon. 2) In a wind tunnel testing of a NASCAR performance, a model is used If the wind tunnel's flow condition (p) is controlled to mimic the exact conditions of the race track, how fast does the air flow in the wind tunnel have to be in order to maintain dynamic similarity a. Keep the Same b. Double the speed c. Triple the speed d. Quadruple the speed a. 3) For an oil cooler with round pipe of diameter of 0.5 inches and the flow condition of Re = 1500, it takes flow this long to establish the fully developed condition: 8 inches b. 25 inches 45 inches d. 50 inches c. 4) For a smooth pipe flow of water with Re = 20.000, the friction factor was found to be f-0.026 (from Moody chart). If the pipe is replaced with a pipe nice the diameter, keeping the same flow rate and conditions, what is the friction factor for the new pipe? a. f = 0.022 b./=0.028 c. f = 0.039 d. f = 0.052 5) The following about turbulent flow in a pipe is true, EXCEPT a) The pipe cross-sectional average velocity is half of the centerline velocity (ie. V=0.5V.) b) The flow Reynolds number is beyond 4100 c) The flow consists of a viscous sublayer, a buflle layer (viscous and turbulent effect both important) and a fully turbulent region up to pipe centerline d) Reynolds-averaged (time mean velocity is used to describe flow velocity 6) The boundary layer (BL) theory does merupply when the following happens. EXCEPT, a. the Reynolds number based on the linear dimension is very small b. there is a boundary layering e. it applies in a turbulent boundary laver en la plat d. the linear dimension of an obite low direction is very, very small

Answer 1

You asked so many questions so i will answer first only.

1 option b will be wrong because no of pi terms is r-1 not r and all rest options are true