A long rectangular copper bar of a cross section of 2cm by 3cm and a long...
A long slender solid cylindrical rod made of copper is 2 cm in diameter. It is taken out of a liquid nitrogen bath at 77 K and exposed to a stream of warm air at a temperature of 50 C. Neglect internal temperature gradients find the time taken by the rod to heat up to a temperature of 10 C if the surface heat transfer coefficient is 20 W/m^2K. For copper, take k=330 W/mK and ?=95*10^-6 m^2/s.
A copper rod is 0.825 m long with a rectangular cross section of dimensions 0.0463 m by 0.0829 m . The ends of the rod are held at 52.7 ∘C and 91.5 ∘C , but the rod is otherwise insulated from its environment. Find the heat current (the amount of heat that flows per unit time) through the rod. The thermal conductivity of copper is 385 W/(m⋅K) . Please show work
copper rod is 0.791 m long with a rectangular cross section of dimensions 0.0451 m by 0.0751 m. The ends of the rod are held at 55.1 'C and 99.1 'C, but the rod is otherwise insulated from its environment. Find the heat current (the amount of heat that flows per unit time) through the rod. The thermal conductivity of copper is 385 W/(m K). heat current
u have a 0.883-m-long copper rod with a rectangular cross section of dimensions 0.0563 m by 0.0753 m. You maintain the ends of the rod at 44.3°C and 92.5°C, but otherwise insulate the rod from its environment. Find the heat current* through the rod. The thermal conductivity of copper is 385 W/(m K) Number ) The heat current is the amount of heat that flows per unit time.
A long, hot AISI 304 stainless steel bar of rectangular cross section has dimensions w = 3 mm, W = 5 mm, and L = 100 mm. The bar is exposed to air that provides a heat transfer coefficient of h = 15 W/m2 · K at all exposed surfaces and air temperature is 300K. Determine an appropriate characteristic length Lc and the corresponding Biot number Bi that is associated with the transient thermal response of the solid object. State...
Consider a rectangular bar of thermal conductivity k W/m-K and total length 2L, as shown in the figure, is connected to a hot surface that is at a temperature T1. The connection between the bar and the surface is imperfect and results in a thermal contact resistance of R’’ m2-K/W. The width of the rod into the depth of the paper is W meters and the thickness of the rod is t meters. The first section of the rod of...
A rigid copper tank, initially containing 1 m^3 of air at 295K, 5 bar, is connected by a valve to a large supply line carrying air at 295K, 15 bar. The valve is opened only as long as required to fill the tank with air to a pressure of 15 bar. Finally, the air in the tank is at 310 K. The copper tank, which has a mass of 20 kg, is at the same temperature as the air in...
4. Air at 200 °C is flowing inside rectangular tube (2cm x 6cm cross section) with velocity 10 m/s. The surface of rectangular tube is assumed as constant heat flux condition. The surface temperature is higher than bulk temperature) by 20 C. Assume the following heat transfer correlation in the rectangular tube. (40 point) 0.03Rea0Pr03 0.81 Nud (a) Calculate hydraulic diameter of the rectangular tube. (b) Calculate Reynolds number and convection heat transfer coefficient. (c) Calculate heat transfer rate for...
**3. A rectangular bar as shown in Fig below is connected between two walls. The bar generates heat at 3500 W/m 3 and is exposed to gas at 18 C with convection coeff. 34 W/m2.K. The wall surface temperatures are kept at 120 C. The bar is divided into 7 divisions with node numbered from 0,1,2.. to 7. The initial temperatures are TO-120 T1-91.11 T2-72.02 T3-62.72 T4-63.22 T5-73.52 T6-93.61 T7-120 C. For t>0 TO and T7 is kept at 120...
A long cylindrical rod of diameter 220 mm with thermal conductivity 0.5 W/m-K expe riences uniform volumetric heat generation of 25,000 W/m3. The rod is encapsulated by a circular sleeve having 7 W/m K. The outer surface of the sleeve is exposed to cross flow of air at 25°C with a convection coefficient of 25 W/m2-K. Find the temperature at the interface between the rod and sleeve, and on the outer surface. an outer diameter of 410 mm and thermal...