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Individual Case Study Vehicles have used disk brakes for decades due to their superior thermal performance (they can be cooled more readily than drum-style brakes)

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Individual Case Study

Vehicles have used disk brakes for decades due to their superior thermal performance (they can be cooled more readily than drum-style brakes). Disc brakes operate by pressing a set of composite material brake pads against a rotating steel wheel disc: the friction between the pads and the disc dissipates the energy of the moving vehicle, resulting in deceleration. The dissipation of the frictional heat generated is critical for effective braking performance.  

In this case study, you will use an Abaqus example to simulate the effect of heating on this brake and the resulting brake performance due to friction as the brake pads press upon a rotating disk. Temperature changes of the brake cause axial and radial deformation; and this change in shape, in turn, affects the contact between the pads and the disc. Thus, the system should be analyzed as a fully coupled thermo-mechanical system.  

A three-dimensional model of the disc with pads touching only part of the circumference is studied. The disc is rotated so that the heat is generated by friction. This problem is solved using both Abaqus/Standard (steady-state solver) and Abaqus/Explicit (transient-state solver). 

You should closely examine the input files provided and report the geometry (including consequences of applying symmetry to this problem, model simplifications compared to the real disk brake model above), material and section properties, the boundary conditions and loads (two steps), the mesh and element type, constraints and contacts, and any other pertinent facts about the model (list parameters clearly in tables). You may find it profitable to import the model in Abaqus/CAE for checkup (need to notice warning messages during the import). 

After simulation, you should plot and report the temperature, stress, contact pressure distribution, and any deformation in both radial and axial cross-section of the disk as well as the inside of the brake pad. You should give thorough discussions of the results and your justifications. How are the static simulations compared to the dynamic simulations (model settings and results)? What physics are missing in the study? How they impact the outcome? Are there hotspots or potential material issues? How to improve the accuracy of the simulations?

You should also perform parametric studies of the model to investigate effects of various factors (material and friction properties, disc loads and speeds, element full and reduced integrations, etc.) and discuss your understandings. You will document your study in a report (minimum 5 pages with figures) containing the sections:

1. Problem description —interpret the Finite Element models (30 points)
2. Discussions of numerical results, including parametric studies (45 points) 
3. Evaluations of results: Do they make sense? What are potential issues and how to improve the simulations? (15 points)  
4. Any outstanding thoughts and efforts demonstrated (10 points)  

A report template example and a paper on disc break analysis are also provided for your reference.