2. Consider laminar boundary layer flow over a flat plate of length L and width W which is maintained at constant surface temperature Ts. The free stream velocity and temperature are V.. and T., respectively. (a) At what distance from the leading edge, D, is the total heat transfer rate from the front section, 0 ≤ x ≤ D, equal to the total heat transfer from back section D ≤ x ≤ L? (b) Which section is shorter, and why? Front D x L Back

HEAT TRANSFER From the heat transfer property table of water, the properties at 20 0C are as follows: Density = 997.36 kg/m3 Kinematic viscosity = 1.026 × 10-6 m2/s Prandtl number = 7.17       (i) Thickness of hydrodynamic boundary layer = 9.24 mm (ii) Thickness of thermal boundary layer = 4.79 mm (iii)Local friction coefficient = 0.001228 Average friction coefficient = 0.002456       ANSWER QUESTION (iv) ,(vi) and B

Air at 305 K flows at 4 m/s over a flat plate at 350 K. The air properties are as follows: density =1.1 kg/m3, viscosity =18.1×10−6 Pa.s, specific heat capacity =1005 J/kgK, and thermal conductivity =0.024 W/mK. The velocity and temperature profiles are assumed to be linear, giving the local Nusselt number to be Nux = 0.289 Rex1/ 2Pr1/3. The flow will become turbulent at a Reynolds number of 5×105. Assume the width of the plate perpendicular to the air flow is 1 m.   At what distance from the leading edge does the flow become turbulent? ________m What is the heat transfer at the point of transition? ___________W What is the total heat transfer along the length of the plate where the flow is laminar? __________W

Water (T= 10 C, , k=0.644 W/m.C, u = 5.54× 10^-7 m2/s, Pr=3.55), flow over plate 1m x 1m , with velocity 2 m/s. the plate surfące temperature is 90 C. Give the answer for the following |-the flow tyPe 2-total het transfer 3-theavargeheat transfer cafficient 4- Nu ?

* ZAIN IQ liı. SuspendEA IN A ROom, Ana TS Subjected To Air Flow Parallel To I... A 2m by 3m flat plate is suspended in a room, and is subjected to air flow parallel to its surfaces along its 3m long side as shown in the figure. The free stream air temperature, T, is 20°C and the velocity is 7 m/s. The total drag force acting on the plate is measured to be 0.86 N. Determine the average convection heat transfer coefficient for the plate. Air 20°C, 7 m/s L= 3 m. This problem has been solved! See the answer

Introduction to heat convection Solved problems HW-10- 1- Determine the velocity distribution in the velocity boundary layer assuming second degree polynomial: u =C, +C,y+C,y? Answer: The boundary conditions are: du .. u = 0 at y = 0; u = u, ; at y = 6; = 0 at y = 8 dy 2 y This gives: يجب حفظ الشروط الحدية اذا كان الامتحان حضوري 2- Determine the velocity distribution in the velocity boundary layer assuming third degree polynomial: u = C, +C,y+C,y' +C,y' Answer: The boundary conditions are: .. u = 0 at y = 0 = 0 dy? at y = 0 du = 0 u = u, at y = 8 at y = 8 dy 3 y 1y This gives: 28 28 يجب حفظ الشروط الحدية اذا كان الامتحان حضوري 3- Determine the velocity distribution in the velocity boundary layer assuming fourth degree polynomial: 2 u = a, +a, y+a,y +a,y' +a,y Answer: The boundary conditions are: . u = 0 = 0 dy? at y = 0 at y = 0 du = 0 dy d'u at y = 6 ; dy? u = u, at y = 6 at y = 6 4. This gives: = 2 يجب حفظ الشروط الحدية اذا كان الامتحان حضوري 4- For flow over a slightly curved…

Consider a flat plate subject to parallel flow (top and bottom) characterized by u = 5 m/s, T = 20 °C. a) Determine the average convection heat transfer coefficient, convection heat transfer rate associated with an L =2 m long, w-3 m wide flat plate for air flow and surface temperatures of Ts = 30 °C and Ts = 80 °C. b) Determine the average convection heat transfer coefficient, convection heat transfer rate associated with an L =0.1 m long, w=0.1 m wide flat plate for water flow and surface temperatures of T = 30 °C and T, = 80 °C.

Consider two cases involving parallel flow of dry air at V = 3.5 m/s, T = 45°C, and atmospheric pressure over an isothermal plate at T = 20°C. In the first case, Rex.c = 5 × 105, while in the second case the flow is tripped to a turbulent state at x = 0m. At what x -location, in m, are the thermal boundary layer thicknesses of the two cases equal? What are the local heat fluxes, in W/m², at this location for the two cases? x = 9'1'am 9 turb = = i i i m W/m² W/m²

Consider the laminar boundary layer flow of an isothermal fluid ( U ∞ , T ∞ ) over a flat isothermal wall ( T 0 ). At a certain distance x from the leading edge, the local skin friction coefficient is C f , x = 0.0066. What is the value of the local Nusselt number at the same location if the Prandtl number is Pr = 7?

Air stream (k = 0.02439 W/m.K, v = * m2/s, Pr = 0.7336) flows over a flat surface [L= 4.5 m, w = 2.5 m] with velocity of 158 km/hr, flow is parallel to L, What is the average convective heat transfer Coefficient "W/m?.°C" ? 1.426 ×10 %3D