Question

In: Mechanical Engineering

A 400-W cylindrical resistance heater is 1 m long and 0.5-cm-diameter. The resistance wire is placed...

A 400-W cylindrical resistance heater is 1 m long and 0.5-cm-diameter. The resistance wire is placed horizontally in a fluid at 20◦C, flowing at a velocity of 20 m/s. Determine the outer surface temperature of the resistance wire in steady operation if the fluid is

(a) air and

(b) water. Ignore any heat transfer by radiation and evaluate properties of air at 800 K and properties of water at 315 K.

Solutions

Expert Solution

Outer surface temperature of wire if fluid is

a) Air is 622.494 ℃

b) Water is 20.715 ℃


Related Solutions

A cylindrical shaped potato with length 2 cm and a diameter of 0.5 cm was dried...
A cylindrical shaped potato with length 2 cm and a diameter of 0.5 cm was dried at a temperature of 65 o C in a convective oven for 24 h, if the surface temperature of the potato remained at 62 o C throughout the drying operation, describe the different changes that occurs during the constant and falling rate periods
1-What is the resistance of a 5km long copper wire with a diameter of 4mm? a....
1-What is the resistance of a 5km long copper wire with a diameter of 4mm? a. 1.65 ohms b. 0.0015 ohms c. .0065 ohms d. 6.7 ohms 2- three 4mF capacitor are connected in series across a 12 V battery. The total charges stored by this compination of capacitor is A. 24 mC B. 16 mC C. 48 mC D. 144 mC E. None of the above 3. What would be the energy stored in the capacitor in the previous...
A long cylindrical object with diameter D=100cm (k=400 W/mK, C­p = 400 J/kg K, density =...
A long cylindrical object with diameter D=100cm (k=400 W/mK, C­p = 400 J/kg K, density = 9000 kg/m3) is put into an oven of 1100 K with convective heat transfer coefficient h of 50 W/m2 K. The initial temperature of this object is 300 K. How much time does it take for the center of the object to reach 700K? How much time does it take for the surface of the object to reach 700K?
A nichrome wire is 15 cm long and has a diameter of 0.25 ??. a) What...
A nichrome wire is 15 cm long and has a diameter of 0.25 ??. a) What is its resistance? b) If a 3.0 V battery is connected across the wire, how much current flows? A wire is 0.4 m long and has a diameter of 1.2 × 10−4 ?. When a 3.0 V battery is connected across the wire, a current of 2.0 × 10−3 ? flows. Determine: c) the resistance of the wire d) the resistivity of the wire
A 33 cm diameter coil consists of 19 turns of cylindrical copper wire 2.8 mm in...
A 33 cm diameter coil consists of 19 turns of cylindrical copper wire 2.8 mm in diameter. A uniform magnetic field, perpendicular to the plane of the coil, changes at a rate of 9.50
Copper wire is wrapped around a cylindrical shell of height h=0.5 cm, forming a “toroid” coil...
Copper wire is wrapped around a cylindrical shell of height h=0.5 cm, forming a “toroid” coil whose inner radius is R1=10 cm and outer radius is R 2 13 cm ( as a result, the cross sectional area of the “toroid” is a rectangle and not a circle; the height of the rectangle is 0.5 cm and the width is 3 cm, as shown in the cross-section view below). The current in the coil is 2A and there are N=500...
What is the resistance of a 2.9-m length of copper wire 1.4 mm in diameter?
What is the resistance of a 2.9-m length of copper wire 1.4 mm in diameter? The resistivity of copper is 1.68×10-8Ω⋅m.
Question 1 a) A cylindrical feedstock of length = 35.4 cm and diameter = 10 cm...
Question 1 a) A cylindrical feedstock of length = 35.4 cm and diameter = 10 cm is subjected to turning using a high speed steel tool. For this tool, n and C values in the Taylor tool life equation are 0.125 and 70 m/min, respectively. The cost for hiring an operator and using the machine tool are $82 per hour. The tooling cost per edge of cutting is $5. Loading and unloading the part on to the machine takes about...
A 1.60 m cylindrical rod of diameter 0.550 cm is connected to a power supply that...
A 1.60 m cylindrical rod of diameter 0.550 cm is connected to a power supply that maintains a constant potential difference of 17.0 V across its ends, while an ammeter measures the current through it. You observe that at room temperature (20.0 ∘ C ) the ammeter reads 18.8 A , while at 92.0 ∘C it reads 17.3 A . You can ignore any thermal expansion of the rod. Part A Find the resistivity and for the material of the...
A 0.5 cm diameter, 50 cm long horizontal tube is connected to a beaker containing n-butyl...
A 0.5 cm diameter, 50 cm long horizontal tube is connected to a beaker containing n-butyl alcohol with the orifice located 10 cm below the surface.   Alcohol(70 degrees F) exits from the tube and drops into another container.    Predict the volumetric flow rate for this system. What is the error if the Bernoulli equation is used?
ADVERTISEMENT
ADVERTISEMENT
ADVERTISEMENT