EG-M83 Assignment 1 EG-M83 - Assessed Coursework 1: Mesh Sensitivity Study This coursework assesses the following AHEP learning outcomes: MEng Semester 2, 2024 MSc • • Ability to apply quantitative and computational methods, using alternative approaches and understanding their limitations, in order to solve engineering problems and implement appropriate action (EA3m) A comprehensive knowledge and understanding of mathematical and computational models relevant to the engineering discipline, and an appreciation of their limitations (SM5m) • Ability both to apply appropriate engineering analysis methods for solving complex problems in engineering and to assess their limitations (EA6m) 1 Problem description The model geometry consists of a heated copper block inside an air filled duct. The dimensions of the geometry are shown in Figure 1. The copper block is heated by a 2.5 W heat source. 0.05 0.05 0.05 0.15 0.10 0.05 0.10 0.05 0.05 0.10 Figure 1 Dimensions of model geometry There are two mechanisms for cooling the system. 1. Heat conduction, where the base and surfaces in the X-Y planes are insulated and the temperature on the remaining outside surfaces of the geometry is fixed at 293 K - see Figure 2. 2. Heat convection, where the copper block is cooled by air flowing over the block - see Figure 3. The air enters the duct through the inlet at a speed of 0.05 m/s and at a temperature of 293 K. The remaining external boundaries are considered to be insulated. A manufacturer wants to know the maximum temperatures that will be reached by the system for the heat conduction case and the heat convection case. 1 EG-M83 293 K 293 K Air Insulated base Assignment 1 Semester 2, 2024 293 K 293 K Figure 2 Schematic of heat conduction problem Copper block inlet 293 K Insulated Air u=0.05 m/s v=0 m/s 293 K outlet p=0 y Copper block ✗ Insulated base, u=v=0 Figure 3 Schematic of heat convection problem 2 Coursework description In this coursework do not generate any meshes with more than 50,000 elements. This is to ensure a sensible computation time. This coursework consists of the following steps: 1. Use ANSYS Fluent to carry out a mesh sensitivity study for the heat conduction case to determine the maximum temperature that will be reached in the system. In this study you should generate 5 meshes using the sweep method. The maximum number of elements in any mesh should be 50,000 or less. This is to ensure a sensible computation time. The report on this phase of work should include: a. The governing equation being solved. b. Details of each of the meshes generated in the study. This should include: i. An image of each mesh. ii. The total number of elements in each mesh. iii. Some information about the strategy you are following when refining the meshes. C. Information about the settings you have imposed to ensure convergence for each simulation. Provide evidence to show that convergence has been achieved. Screenshots can be used here. 2 EG-M83 Assignment 1 Semester 2, 2024 d. A summary of the key results from your simulations and consideration of mesh independence. This should include i. A table or graph comparing the maximum temperatures obtained on each mesh. ii. Any relevant results plots iii. Some discussion and analysis about the maximum temperature in the system iv. Consideration of whether it is possible to obtain mesh independent results for this system within the 50,000 element mesh limits imposed here. Make recommendations for the meshing strategy that should be followed for future heat conduction simulations for this geometry based on your analysis. (44 marks out of 100) 2. Using only the meshes developed for the heat conduction case, carry out a mesh sensitivity study for the heat convection case to determine the maximum temperature that will be reached in the system. The report on this phase of work should include: a. The governing equations being solved. b. Information about the settings you have imposed to ensure convergence for each simulation. Provide evidence to show that convergence has been achieved. Screenshots can be used here. C. A summary of the key results from your simulations. This should include: i. A table or graph comparing the maximum temperatures obtained on each mesh. ii. A table or graph comparing the maximum velocities obtained on each mesh. iii. Any other relevant results plots to illustrate your discussion. iv. Some discussion and analysis about the maximum temperature in the system, including some consideration about how this is influenced by the air flow as the mesh is refined. v. Consideration of whether it is possible to obtain mesh independent results for this system within the 50,000 element mesh limits imposed here. Make recommendations for the meshing strategy that should be followed for future heat convection simulations for this geometry based on your analysis. (38 marks out of 100) 3. Use the finest mesh you have generated, change the base boundary condition type from wall to symmetry. What effect, if any, does this have on the solution for the heat conduction and heat convection cases? Give an explanation for your observations. (10 marks out of 100) Marks will be awarded for report layout/quality. The report should be no longer than 15 pages. From experience, the length of a typical report for this coursework will be between 10 and 15 pages depending on the size and quantity of images included. 3 (8 marks out of 100) EG-M83 Assignment 1 Semester 2, 2024 3 Assignment submission instructions Submit the written report through the Assignment 1 submission point on Canvas. Include a copy of the Coursework Cover Sheet form (this will not be included in the page count). Technical assistance with the software tools will be available in the PC labs and module office hours. 4 Marking scheme A breakdown of the marking scheme is shown below: Criteria % Q1: Conduction (44%) Full definition of governing equations Mesh details (images, strategy, 4 number of elements) 14 10 Convergence discussion/evidence Key results/plots, discussion and analysis Meshing recommendations or strategy to ensure independence 11 5 Q2: Convection (38%) Full definition of governing equations Convergence discussion/evidence 5 10 Air flow discussion Key results/plots and analysis Meshing recommendations or strategy 13 5 to ensure independence 5 Q3: Base boundary conditions (10%) Report quality (8%) Total Results 5 Discussion 5 Presentation, structure, captions, labelling, units 8 100 4