Problem 1: Consider laminar pipe flow having a thermal entrance region and constant wall temperat...
Which of the following statements are true (could be multiple) for internal flow through a pipe? In laminar flow, the Nusselt is higher for constant wall temperature compared to that for constant heat flux. In turbulent flow, the Nusselt number is higher at the pipe exit than at the pipe entrance In laminar flow, the Nusselt number is lower at the pipe exit than at the pipe entrance In laminar fully developed flow, the Nusselt number is independent of Reynolds...
Consider a 30 m long pipe with a diameter of 1 cm and with a smooth interior wall surface. The pipe wall temperature is kept constant at 60 C. (a) Some liquid enters the pipe with a tempera- ture of 20° C and exits the pipe with a mix- ing cup (bulk) temperature of 57°C. Know- ing that the mass flow rate of the liquid is of 0.015 kg/s, that the liquid density is of 1000 kg/m 3, that the...
Use the integral method for boundary layer flow and convective heat transfer over a flat plate heated by maintaining a constant heat flux q"w, for the case of very low Prandtl number, Pr0. Assume that the free stream velocity of the fluid, U, and free stream temperature, T-do not vary with x. Using the integral form of energy equation, show that under these conditions: (a) the temperature profile, (T- T) is given by, 41 2 CT-T oa (b) the wall...
Fluid Mechanics #1 Laminar Flow in Pipes The axial velocity in a pipe of radius R is given by, . Find the value of r (as a fraction of R) that maximizes u(r). How does this value of velocity compare with Vc? Compute the wall shear stress, du or Perform a control volume analysis on a pipe section of length e. Relate the pressure drop across the pipe section to the shear stress. Substitute the relation above for tw to...
use table A-15 kinematic viscosity 6. Consider a 2-m long smooth cylindrical pipe of 5 cm internal diameter, that is maintained at a constant surface temperature. Air flows through the tube at 0.5 m/s. Air enters the pipe at 20°C and leaves it at 60°C. Determine: (a) Is the flow laminar or turbulent? (b) Is the flow fully developed? (c) What Nu number correlation will you use to find h? Find Nu. (d) Find the convection heat transfer coefficient (h)...
Problem 5. Consider a (i) steady, (ii) incompressible, axisymmetric, (iv) fully- developed, (v) constant viscosity, (vi) laminar flow in a circular pipe. Assume that the pipe is horizontal, so that any gravitational effects can be ignored It is known that an incompressible, constant viscosity fluid can be described by the continuity equation in cylindrical coordinates together with the Naiver-Stokes equations (ak.a., momentum eqns) in cylindrical coor- dinates Ov 00. Or 9-moment um 11ap 2-momentum plus the appropriate boundary conditions. Starting...
Problem 1 It is known that for a laminar flow through a round pipe ф(ND)-32 VD, where "I" and "D" are length and diameter of the pipe, respectively Consider a fully developed, laminar flow Q- through two horizontal smooth pipes of equal ength. The pressure drop for the first pipe is 1.44 times greater than is for the second pipe If the diameter of the first pipe is D, determine the diameter of the second pipe. Neglect the minor losses
4. Consider upwards, laminar flow in a vertical pipe of length L. (a) Starting with the NS equations given in 6.128 c. simplify the eq'ns, state the BCs in the coordinate system shown, solve for vír), wall shear stress tw, and the average flow speed V=Q/rR; (b) rearrange your result into the form , like EB CV relation, (AP/pg +1)=f* (LD)V/(29) for arbitrary length L, and show that the friction factor f= C2/Rc and evaluate C2 as a number. Follow...
PROBLEM 1: Answer/Define/Explain shortly and/or Fill in the blanks (40 P) a) What are the two types of energy transfer in Convection? b) A thermal boundary layer must develop if ....... c) Define the critical Reynolds number. d) What are the assumptions for Boundary Layer Equations for Laminar Flow? e) Define the Nusselt number. f) Define the Prandtl number. g) How the Pr influences the relative growth of the boundary layers, explain briefly ? h) Explain favorable pressure gradient. i)...
1. Is the floe within the pipe turbulent or laminar? Justify your answer 2. What is the average Nusselt number and heat transfer coefficient in the pipe? You can assume that the flow is fully developed 3. What length of pipe is required to achieve the desired exit temperature? 4. Was your assumption of fully developed flow justified? Explain why or why not. How much error did this assumption introduce into calculation of nusselt number? Do you need more or...