Module 3 - Experiment Design

Question 1

What is the goal of the experimentalist?

Answer 1

Determine the model function (behaviour of the system being studied) by observing the output as inputs are varied

Question 2

Why is a literature review important in the early stages of experiment design?

Answer 2

• Determine if the experiment is required (is there data on this already)
• predict the costs and time required for the experiment
• Determine what techniques have been used in the past
• identify any test standards
• identify efficient ways to conduct experiment
  Main goal is to reduce monetary and time investment

Question 3

What is the iterative experimental loop?

Answer 3

1. Define objectives
2. Select approach
3. Parametric design
4. Hardware design and instrument selection
5. Construction
6. Commissioning
7. Data collection
8. Data reduction and analysis
9. Reporting

Question 4

What are two factors that can influence the range of an independent variable on a parametric map?

Answer 4

• Absolute physical limits (ie 0K)
• Equipment limitations (ie max flow rates)
• Measurement uncertainties

Question 5

Why would you randomize a test trajectory?

Answer 5

Reduce the effects of temporal effects (ie heating of the air in a closed return wind tunnel) to avoid drawing errant conclusions that were actually due to temporal effects

Question 6

What are some advantages of performing a qualitative assessment?
What are some flow features that may be observed?

Answer 6

• provide insight into expected results, assess whether proper measurements are required, evaluate effectiveness of current approach, select instruments, reveal unexpected flow features, identify flaws in equipment
• leaks, cross-streams, swirling flow, separation bubbles, mixing layers, instabilities in a jet, flow direction, multiphase flow, layered flow, turbulent Bls, coherent flow steuctures