The ultimate guide to passing technical SOPEEC Power Engineering exams

The SOPEEC exams are tough and some consider them poorly-suited to their profession. Roughly 41% of students fail the SOPEEC exams - OUCH. I studied  engineering at a university in Canada and recognize the much of the materials as curated works of my 1st and 2nd year university-level engineering courses. 

Yet, you must pass the exams  and to make it tougher the suggested study materials do a poor job of covering the material you're tested on. So we'll pass along the tried, tested and true study methods that engineers use to pass very technical examinations in as little time as possible.

But beware, the number one mistake in preparation for these exams is to simply read and review the suggested materials.  For exams this challenging, the majority of preparation time must be spent working through problems just as you would in an exam.

You need to get your hands dirty. Start with a question and a blank sheet of paper, work through the steps, stopping to get more information as required to work your way through problems.  This is the only way to ensure a solid understanding.  This is the only way to ensure you'll do well on the exam and we'll walk you through that today.

But ensure you leave time for a laugh as well with these hilarious engineering jokes. 

3 step SOPEEC exam preparation process

An age old preparation process has proven very valuable, time and time again.  This three step process is simple but takes time.  The challenge is in the discipline to carry the process out. 

Step One is to work through problems in which you are provided the answers.  A great example of this is the simple problems provided in your Pan Global materials or other textbooks.  Grab a piece of paper and try to do the example without looking at the solution.   

Step Two is to work through problems that are more challenging.  In a technical classroom setting this step includes working through and understanding all the assignments that were done throughout the year. In a self study setting this includes working through end of chapter questions in your Pan Global materials. By now you should seldom resort to the solutions.  

Step Three must include working through exam style questions.  It is critical to practice the type of questions that you will see during the exam.  An exam is a poor place to be frantically flipping through a textbook searching of new knowledge. In a technical classroom setting past exams are very often provided.  In the SOPEEC setting, past exams are unfortunately not available.  

I can tell you from first hand experience that if you set aside the time to perform all three of these steps, you will do very well on your exam.  

Step 1: Textbook examples

Lets take a look at this three step process with a 2A2 Thermo and Materials example.  Work through these Pan Global examples and then try to solve them yourself (with a pen and paper, without the videos).

1-1 Partial Pressures

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A Pan Global Thermodynamics example dealing with partial pressures of ideal gases.  
​Important takeaways: 

• Partial pressures only works for gases (dry air and water vapour in this case).

• Two gases in the same container will both occupy the full volume of that container and not half that volume.  
• The ideal gas law must utilize absolute pressure and an absolute temperature scale, in our case the Kelvin temperature scale.  
• Air is composed of gasses dry air and water vapour.  It is reasonable to consider that air is an ideal gas since it is composed of 78% Nitrogen (ideal gas) and 20% Oxygen (ideal gas).  
• Since we were supplied a gas constant, we can very easily assume we must utilize the ideal gas law.​

1-2 Ideal Gas Law

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An example using units of temperature (Celsius, Kelvin and Fahrenheit), pressure (kilo pascals, mega pascals, pounds per square inch) and some may be gauge pressure and some may be atmospheric pressure.
​Important takeaways:

• If you are given gauge pressure, add add 101.3 kPa to make it an absolute pressure.  P(absolute) = P(gauge) + P(atmospheric)
• Remember that we must do these ideal gas calculations in the Kelvin scale by adding 273 K to any temperature given in Celsius.  
• Since we were supplied a gas constant, we can very easily assume we must use the ideal gas law. 
• A compressor gas rate is most often given in standard conditions, that is why we utilize standard cubic meters per minute (sm3/min).  In actual conditions (typically a much higher pressure and much higher temperature) the rate is much higher.  To size equipment you will definitely want to know the actual rate.  

1-3 Simple Heat Transfer

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A lesson on using the simple heat transfer equation.  One given coefficient of heat is a value under constant pressure conditions and another coefficient of heat is a value under constant volume conditions.
​Important takeaways: 

• Remember that the temperature units of Cv or Cp do not matter since they are a difference.  Do not try to make the conversion that I point out at the end of the video.  
• Remember that if you are given gauge you must add 101.3 kPa to the pressure to make it an absolute pressure.  P(absolute) = P(gauge) + P(atmospheric)
• Remember that we must do these ideal gas calculations in the Kelvin scale by adding 273 K to any temperature given in Celsius.   
• Since we were supplied a gas constant, we can very easily assume we must utilize the ideal gas law.  
• Watch your units, note our gas constant includes KJ but our coefficient of heats include J.  

1-4 Work Formulas

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This video is a thorough explanation of the different work formulas and when to utilize them.    
​Important takeaways:

• isobaric - a process occurring at constant pressure
• isothermal - a process occurring at constant temperature, almost impossible in reality but good for modelling purposes.  
• adiabatic - an assumption in which no heat is gained from or lost to the surroundings.  Realize that the temperature of the liquid or gas can change but we are essentially perfectly insulated.  
• polytropic - is an experimental determined assumption that includes a more real world situation in which heat changes, pressure changes and temperature changes. 
• Throttling is an adiabatic process and a means of choking flow and creating a pressure drop across a valve or some sort of orifice (giggity).  Thus the assumption of adiabatic conditions will not be mentioned in the question, you must recognize it and apply the formula mentioned in the video. 

1-5 Interpolation

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This is not only a lesson in the math behind interpolation but a great lesson in recalling the formula to interpolate. Interpolation gives us a method to determine the point you are after by simply drawing a straight line between the two points.  This method is simply termed linear interpolation and is explained in the video.  Important takeaways: 

• Unfortunately we must memorize this technique and the formulas associated with it.  Thus I hope the following makes it quite easy for you:
• y = mx + b    
• y = m(x - x0) + y0
• where m is rise over run

1-6 Steam Phase Diagrams

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The steam phase diagram (Temperature versus enthalpy) is critical to understanding the phase changes involved with steam, and steam quality.  
​Important takeaways:

• Boiling points increase with pressure, but they all basically fall on the line 1-2
• Once you reach the boiling point at a particular pressure, then the temperature and pressure does not change until you convert all the water to steam.  
• Saturated liquid is the left side of the dome.
• Saturated gas or dry steam is on the right side of the dome.
• Further out from the dry steam line is a superheated region in which temperature increases are seen as more heat is added. 
• Wet steam is the area inside of the dome and is described as various qualities of steam.
• Just like it takes a certain amount of energy to convert water to steam, there is a very similar process to convert ice to water in which the temperature does not increase during melting.  Thus it is also termed an isothermal process.    
  

1-7 Steam Table Applications

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This video does not involve a lot of math but that is done purposely.  Before we get into the math I want to ensure you understand how we apply the phase diagrams to the different types of problems.  I also want to ensure you understand how we get data from the steam tables.  
​Important takeaways: 

• Boiling points increase with pressure; however, they all basically fall on the line 1-2
• Once you reach the boiling point at a particular pressure, then the temperature and pressure does not change until you convert all the water to steam.  
• Saturated liquid is the left side of the dome, saturated gas or dry steam is on the right side of the dome.  Further out from the dry steam line is a superheated region in which temperature increases are seen as more heat is added.  Wet steam is the area inside of the dome and is described as various qualities of steam.
• If a liquid is below the boiling temperature we must use temperature to determine its values in the chart.  If we used the pressure we would be determining values at the boiling point since the pressure values in the chart describe a saturated liquid state.  

Step 2: Assignment questions

Work through an assignment style question or an end of chapter Pan Global question. Again, tackle this question on your own and sort out where you are confused.  I often keep notes on all my confusions and tackle those at the end.  You must have this material straight in your head as so often exam question are focused on the harder to understand details that are very likely in your list.

Step 3: Exam questions

 In this step we are looking to get as close as we can to  SOPEEC exam question style.  Unfortunately they are not publicly available, but here is an example exam question. Once again, ensure you understand the details.