Using pdetool GUI
This In many situations, students perceive programming as troublesome and tedious. This phenomenon lies on the fact that programming may be difficult to the novice. A missing comma can cause a major headache for the debugger. Hence it is useful to initially attract the students' interests by showing the simpler solutions to any engineering problems. The application of pdetool GUI is one of the many ways to accomplish this. In this case, PDE can be implicitly solved by plugging in a few parameters in the GUI as explained in the methodology section.
A set of pdetool GUI outputs is illustrated in Figure 6. It is worth to note that the graphical results of the pdetool GUI may vary depending on the mesh size. The finer the mesh the smoother the temperature profiles will be but the longer it will take for MATLAB to obtain the solution. Figure 6.a depicts the mesh grid at the second level refinement, which was found optimum(with respect to the balance between accuracy and computing time) for the heat transfer problem posed in this work.
Figures 6.b-f show the resultant temperature profiles of the side view from 1 hr to 5 hr duration. Initially(0 hr), the system is at an initial temperature of 10 oC, which is the temperature of the incoming cold fluid. After an hour of constant radiation at the outer tube wall, the system temperature starts to gradually increase and shows curvature profiles. These temperature profiles vary according to the prescribed boundary condition specifications, of which the inlet and outlet temperatures are respectively set at 10 oC and 60 oC. The outer tube wall is exposed to the uniform radiative heat transfer and the inner side with the convective boundary condition Consequently, the temperature profiles depict higher values(in terms of colour variation) at the top and right sides of the tube
As the simulation time increases, indicating more radiative exposure to the outer tube wall, the higher temperature profiles move deeper diagonally to the left side of the wall. This phenomenon is clearly depicted by the change of colour from dark blue to the lighter blue and