Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)
8th Edition
ISBN: 9781305387102
Author: Kreith, Frank; Manglik, Raj M.
Publisher: Cengage Learning
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Chapter 5, Problem 5.8P
To determine
Towing speed for the model ship.
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1. The thrust of a marine propeller Fr depends on water density p, propeller diameter D, speed of advance
through the water V, acceleration due to gravity g, the angular speed of the propeller w, the water pressure
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depends. In other words
CT =
FT
· = ƒen(#1, #2, ...)
pV2D2
(a) What is k? Explain.
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(1)
An underwater device which is 2m long is to be moved at 4 m/sec. If a geometrically
similar model 40 cm long is tested in a variable pressure wind tunnel at a speed of 60
m/sec with the following information,
Poir at Standard atmospheric pressure = 1.18kg/m³
Pwater = 998kg/m3
Hair = 1.80 x 10-5 Pa-s at local atmospheric pressure and
Hwater = 1 × 10-3 Pa-s then the pressure of the air in the model used
times local atmospheric pressure
is
A student team is to design a submarine for a design competition. The overall
length of the prototype submarine is 4.85 m. The prototype submarine is
expected to moves through freshwater in the lake at 0.440 m/s. The student team
builds a one-fifth scale model to test in their university's wind tunnel. Calculate
the wind tunnel air speed in order to achieve similarity with the prototype
submarine. For water at T= 15 °C and atmospheric pressure, the density is p =
999.1 kg/m³ and the dynamic viscosity is µ = 1.138 x 10³ kg/m-s. For air in the
wind tunnel at T= 25 °C and atmospheric pressure, the density is p= 1.184 kg/m³
and the dynamic viscosity is µ = 1.849 x 10-$ kg/m's.
Chapter 5 Solutions
Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)
Ch. 5 - Evaluate the Reynolds number for flow over a tube...Ch. 5 - 5.2 Evaluate the Prandtl number from the following...Ch. 5 - Evaluate the Nusselt number for flow over a sphere...Ch. 5 - 5.4 Evaluate the Stanton number for flow over a...Ch. 5 - Evaluate the dimensionless groups hcD/k,UD/, and...Ch. 5 - 5.6 A fluid flows at 5 over a wide, flat plate 15...Ch. 5 - 5.7 The average Reynolds number for air passing in...Ch. 5 - Prob. 5.8PCh. 5 - When a sphere falls freely through a homogeneous...Ch. 5 - 5.10 Experiments have been performed on the...
Ch. 5 - 5.13 The torque due to the frictional resistance...Ch. 5 - The drag on an airplane wing in flight is known to...Ch. 5 - 5.19 Suppose that the graph below shows measured...Ch. 5 - Engine oil at 100C flows over and parallel to a...Ch. 5 - For flow over a slightly curved isothermal...Ch. 5 - Air at 20C flows at 1 m/s between two parallel...Ch. 5 - Air at 1000C flows at an inlet velocity of 2 m/s...Ch. 5 -
5.43 A refrigeration truck is traveling at 130...Ch. 5 - The air-conditioning system in a Chevrolet van for...Ch. 5 - Determine the rate of heat loss from the wall of a...
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