CHBE 264 - Marking Sheet for Expt. C (Thermo) Short Report 95 marks Assignment Cover Sheet (1 mark) · Completed accurately (names, group number): 0.25 · Max word count (1500 +/- 15%): 0.5 · Boxes checked and signatures: 0.25 Report (55 marks) Summary (10 marks) 1. Objectives of the experiment ( /3) 2. Techniques used and systems studied ( /3) 3. Important results ( /3) 4. Conclusions ( /1) Results and Discussion (35 marks) Note: write in concise paragraphs, not numbered responses. Your sentences should flow smoothly while providing the information requested below. Incorporate plots and tables as needed and refer to them in the text. 1. In the Compressibility Factors experiment, what is the consequence for NOT purging the system before taking the pressure measurements? ( /2) 2. Why is running the Compressibility Factors experiment at constant temperature important? How would a fluctuating ambient temperature (+/-5 °C, for example) affect the experiment? What measure can be taken to avoid such temperature fluctuations? ( /3) 3. Comment on the volume ratio between VB (carboy) vs. VA (cylinder) in calculating the compressibility factor. Why is this value important? ( /3) 4. Explain why the ideal gas law can be used for the bigger tank in Compressibility Factor experiment. ( /2)
5. Discuss the behavior of compressibility factor vs. pressure plot. How does the result agree with the literature? ( /3) 6. What other gases can be studied in the Compressibility Factor experiment? How would the Z vs. pressure plot change compared with the case for CO2 and He? List two safety concerns. ( /3) 7. Comment on the virial coefficients obtained using both linear and quadratic fits. (/3) 8. Explain why the pressure-enthalpy diagram is important. ( /2) 9. Comment on the pressure-enthalpy diagram for each of your trials. ( /3) 10. Comment on specific refrigeration capacity, specific cooling capacity, and the compressor work of each trial.( /2) 11. What effect does the compression ratio have on the performance of the system? Why might this be? ( /3) 12. Calculate the heat absorbed and released by the system. ( /2) 13. Compare the heat absorbed in the evaporator and the refrigeration capacity, do the values make sense? ( /2) 14. Sources of error in Part 3: Refrigeration cycle ( /2) Conclusions and Recommendations (10 marks) 1. Concise summary of experiment and results (4 marks) 2. Limitations and uncertainty in the execution of the experiment and the results (3 marks) 3. New ideas and recommendations if you were to repeat this experiment (3 marks) Template File (10 marks) 1. Completion of all parts of the template file ( /2) 2. Accuracy of calculations ( /8)
Appendices (20 marks) 1. Appendix A - Raw and Calculated Data Tables + Supplemental Figures ( /5) 2. Appendix B - Sample Calculations ( /8) 3. Appendix C - Error Analysis ( /7) Presentation (9 marks) 1. Format ( /3) 2. Organization ( /3) 3. Grammar, spelling, correct use of verb tenses, clarity etc. ( /3)