Computer simulations are applied everywhere in engineering and it has placed a huge amount of burden on top level managers responsible for taking critical designs. Prior to the simulation era, making engineering decisions were simply based on few physical measurements, some handful of experimental data and engineering drawings.
However, the present simulation driven design approach has made the decision making process much more complex. Since these tools are employed prior to design release, the decisions to be taken rely heavily on the simulation results quality.
Computer aided simulations helps in answering how, what if, when and where questions pertaining to the product design. It is therefore crucial to ensure the reliability of the simulation results as they play an important role in finalizing the design. Unless reliable, the management team can expect some highly disastrous outcomes due to decisions taken based on simulation results. The promise of a new innovative product may never reach to the marketplace, or the flaw in a product could lead to excessive warranty and replacement costs.
In such circumstances, it is always better to verify the simulation results before proceeding further. Verification requires identifying the reliability of the simulation process based on previous work performed, or comparing the results to experimental tests conducted before. It is always important for the managers to realize that simulations are always performed with underlying assumptions.
A usual tendency of an analyst is to avoid adding the assumptions part in the report, which can certainly lead to dramatic decisions. When pressed for explanations, they often provide mathematical formulas used to perform the physics work.
However, the information from the simulation should be transparent and should have straight forward answers against mathematical equations. Some common reliability questions that must be asked can include:
- How well the boundary conditions utilized for the analysis meets the real physical condition
- Numerical values of the physical properties of the material being used
- How many number of load steps are utilized and are those load steps sufficient enough to ensure that nothing is missed out?
- How accurately the bolts and weld joints are represented in the analysis?
- What type of analysis is being used, i.e. linear or nonlinear? Would it be possible to obtain results by simply performing physical measurements?
- In case of fluid dynamics, how well the fluid flow is modeled? What type of turbulence model is used?
Questioning is highly important to ensure that the simulation driven design is on the right track. It should be an additional tool to determine the accuracy of the analyses being performed. It should be noted that a computational model will not give the right answer until it is being compared with the reality. Simulation can only become reliable and a boon for manufacturers until it has been verified; or else, there are heavy chances of design process to become paralyzed and meaningless.
Image Credit: http://www.jhuapl.edu/techdigest/TD/td2502/Pace.pdf