Estimate the tempreture measured by thermocouples, Mechanical Engineering

An experiment to determine the convection coefficient associated with airflow over the surface of a thick stainless steel casting involves insertion of thermocouples in the casting at distances of 10 mm and 20 mm from the surface.  When the experiment was performed in a well insulated air duct so that the temperature of the walls surrounding the steel surface was the same as the air temperature, the thermocouples measured the temperatures of 50°C and 40°C in the steel, respectively, when the air and the surrounding wall temperatures were 200oC.

a)    If the steel has a thermal conductivity of 15 W/m2K and surface emissivity of 0.95, what is the convection coefficient between the steel and hot air?

b)     What are the contributions of the convective and radiation heat fluxes to the steel casting?

In the repeated experiments the duct insulation was removed and even though the hot air temperature was the same as before, i.e., 200oC, the surrounding walls temperature dropped to 20oC. As a result the steady state heat flux to the steel casting dropped by 13.3% compared to the first experiment.

c)   Assuming the same convection coefficient as the value calculated in part a), what would be the temperatures measured by the thermocouples?

d)    Suppose that the steel casting were well insulated from all sides except for the surface from which the distance to thermocouples is measured. Assuming the same convection coefficient as the value calculated in part a), what would be the temperatures of the thermocouples when:

i)  The experiment is performed in the well insulated duct at T = Tsurr = 200oC?

ii)  The experiment is performed in non-insulated duct at T = 100oC and Tsurr = 20oC?

Posted Date: 3/19/2013 1:32:24 AM | Location : United States







Related Discussions:- Estimate the tempreture measured by thermocouples, Assignment Help, Ask Question on Estimate the tempreture measured by thermocouples, Get Answer, Expert's Help, Estimate the tempreture measured by thermocouples Discussions

Write discussion on Estimate the tempreture measured by thermocouples
Your posts are moderated
Related Questions
What are the factors responsible for the development of newer tool materials. Explain several materials used for cutting tools. List four kinds of tool wear.

Swing Arm Shock Absorber :   This type of suspension is used to serve for rear part of motorcycle. The advantage of this type of suspension is that large deflections are absorbed.


Stitch Welding This is a variation of spot welding, in which a series of overlapping spot welds are made in the same manner as stitching cloth. Stitch welding may be performed

Steps of servicing   Bring the motorcycle in the washing bay. Clean the motorcycle with recommended soap solution and soft sponge. Wash the motorcycle with a jet o

This section covers welding of pressure parts including those non-pressure parts when welded to pressure parts. All welding design functions necessary within the contract shall be

In a sun and planet type gear, the annular gear (D) has 100 internal teeth, the sun gear (A) has 50 external teeth and a planet gear (B) has 25 external teeth. The gear (B) meshes

System of loads -  Beam: Build the SFD & BMD for 10 m span simply supported beam subjected to a system of loads as illustrated in Figure . Figure Taking moment a

Q. Explain about Active Fire Protection? Active Fire Protection - A fire fighting system that is normally dormant and is activated automatically upon detection of a fire hazard

What is a newton ring excrement