Simple heat conduction problem setup

In summary, a thermometer mounted through the wall of a steam pipe has a steel tube with 0.1 in wall thickness, 0.5 in outer diameter, 2 in length, and a thermal conductivity of k=26W/(mK). The outside surface of the well experiences a convection heat transfer coefficient of 100W/(m^2K). With a thermometer reading of 149 deg C and a pipe temperature of 65 deg C, the average steam temperature can be estimated by balancing the heat convected into the well from the steam with the heat conducted through the well to the outside surface of the pipe. This can be represented by the equation: hA_{1}(T_{steam} - T_{pipe
  • #1
mahdert
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Homework Statement



a thermometer wall mounted through the wall of a steam pipe is a steel tube with 0.1 in wall thickness, 0.5 in outer diameter, 2 in length and k=26W/(mK). The flow produces an h value of 100W/(m^2K) on the outside surface of the well. If the thermometer reads 149 deg C, and the temp. of the pipe is 65 deg C, estimate the average steam temp.


Homework Equations



Fouriers law of cunduction: q = -k A [tex]\frac{\partial T}{\partial x}[/tex]
Newtons law of cooling: q = hA(T[tex]_{\infty}[/tex] - T)

The Attempt at a Solution


Just need help with the problem setup:
A heat balance between the heat convected into the well from the steam is equal to the heat conducted through the thermometer well to the outside surface of the pipe. Heat conduction occurs axially through the pipe, in other words, there is no temperature difference inside the pipe in the radial direction. (is this a correct assumption).

The convection occurs throught the outside surface of the well and the bottom surface that is exposed. (is this a correct assumption).
 
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  • #2
Therefore, the heat balance equation is: hA_{1}(T_{steam} - T_{pipe}) = kA_{2} \frac{\partial T}{\partial x} + hA_{3}(T_{infty} - T_{pipe})where A_{1} = circumference*length, A_{2} = pi*2in*0.1in, A_{3} = area of bottomI am not sure how to solve this equation for T_{steam}.
 

FAQ: Simple heat conduction problem setup

What is a simple heat conduction problem setup?

A simple heat conduction problem setup is a simplified model used by scientists and engineers to study heat transfer through a material or system. It involves a uniform material with a known temperature gradient, and the goal is to determine the rate of heat transfer through the material.

How do you set up a simple heat conduction problem?

To set up a simple heat conduction problem, you need to define the material properties (such as thermal conductivity and specific heat), the boundary conditions (temperature at each end), and the initial temperature distribution. These parameters can then be used to solve the heat conduction equation and determine the temperature profile and heat transfer rate through the material.

What are the assumptions made in a simple heat conduction problem setup?

The main assumptions made in a simple heat conduction problem setup include: the material is homogeneous and isotropic, the temperature gradient is small, and there is no internal heat generation. Additionally, the heat conduction is assumed to be one-dimensional, meaning that the temperature only varies in one direction. These assumptions allow for a simplified model that is easier to solve mathematically.

What are some real-world applications of simple heat conduction problem setups?

Simple heat conduction problem setups are used to study heat transfer in various systems, such as building insulation, electronic devices, and industrial processes. They are also used to design efficient heat exchangers, refrigeration systems, and thermal management systems. In addition, simple heat conduction problems can help predict the thermal behavior of materials under different conditions, which is crucial in fields like material science and engineering.

What are the limitations of using a simple heat conduction problem setup?

While simple heat conduction problem setups provide valuable insights into heat transfer processes, they have some limitations. One of the main limitations is that they do not account for the effects of convection and radiation, which are significant in many real-world scenarios. Additionally, the assumptions made in the model may not always hold true, and more complex mathematical models may be required to accurately predict heat transfer in certain situations.

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