Investigation of Explosion in Mach 2 Supersonic Wind Tunnel

What happened in the Mach 2 supersonic wind tunnel?

As the Chief Engineer of the Sherlock Holmes Aerospace Detective Agency, you have been asked to investigate the suspicious explosion of a recently constructed Mach 2 supersonic wind tunnel. The wind tunnel was designed in the standard configuration: a large tank containing air of pressure 200 kPa, temperature 100 C, Cp = 1000 J/kgK , R = 287 J/kgK, and gamma =1.4, a converging-diverging nozzle, and an exit flow that exhausts into an open testing room. Created specifically for this wind tunnel, both the tank and the nozzle were fabricated from a new super 
duper tensile strength material, UOTSD.60, which can resist pressure differences of up to 60 kPa. Just before the wind tunnel exploded, the exit flow of the Mach 2 nozzle was measured to be 160 m/s.

Based on your calculations and superior knowledge of Gas Dynamics, you have been asked to prove that either the tank exploded, the nozzle exploded, or as the designers would prefer to believe, that some jealous rivals used an explosive device to sabotage their impressive 
Bernoulli-based Supersonic Wind Tunnel Facility, BS-WTF.

You are required to produce a Zoom presentation that is both thoughtful and elegant, worthy of your title as Chief Engineer. Your presentation should be clear and simple, easy to follow, and focused enough to explain your conclusions to the general audience of a Lawsuit Judge and 
Jury; or a room full of Science-Technology-Engineering-Art-Math (STEAM) loving 10 year olds. 

Your Zoom presentation should explain your thought process, identify your important decisions as you navigate through your calculations, and lead your viewers to your obvious and logical conclusions to the 5 questions that you’ve been asked to answer.

You are also required to submit a one page Executive Summary that encapsulates your more detailed Zoom presentation with a couple of sentences to reiterate your conclusions for each of the 5 questions that you’ve been asked to answer. Your summaries should be clean, clear, and concise; uncluttered by any calculations or unnecessary details. Your Executive Summary is where your grades will be recorded and returned to you.

Your Zoom Presentation, and Executive Summary, should follow and answer the sequence of 5 questions outlined below:

1) A brief conceptual introduction to your analysis that summarizes the flow through the wind tunnel and identifies the specific data that will be needed to prove that: a) the tank exploded, or b) the nozzle exploded, or c) that an explosive device must have been used to sabotage this new Bernoulli-based Supersonic Wind Tunnel Facility, since neither options a) or b) are possible.    5 Marks

2) Describe with diagrams and calculations, how this wind tunnel would/could/should have produced the desired steady state, supersonic design, exit flow. 10 Marks

3) Describe with diagrams and calculations, how this wind tunnel actually performed. Why didn’t this wind tunnel perform as the designers had hoped? What was the “fatal” or major mistake that was made? 20 Marks

4) Describe with diagrams and calculations, how you can prove and identify where this wind tunnel actually ruptured and exploded, or if it was instead sabotaged. 10 Marks

5) Since the designers insist that their 160 m/s exhaust flow was correct, and they continue to believe that they did in fact produce a supersonic exit flow, show why their Bernoulli equation calculations would never have predicted this explosion. Explain why their Bernoulli calculations made them believe, incorrectly, that a supersonic flow should have been produced as it exited the nozzle and flowed into the testing room. Show that, even if the numbers obtained from Bernoulli’s Equation were correct, the flow that exited the nozzle would not have been a Mach 2 flow.   5 Marks