{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

HW4QuestionsAnswersME525SP2011

HW4QuestionsAnswersME525SP2011 - 1 ME 525 SP2011 Homework#3...

Info icon This preview shows pages 1–2. Sign up to view the full content.

View Full Document Right Arrow Icon
1 ME 525 SP2011 Homework #3 Questions and Answers Due Thursday, March 10, 2011 Prof. Lucht (E-mail address: [email protected]) Question: Here is what I have come up with so far. I put my work into excel. I was working question 3 and saw that the fuel was CH3OH and I was wondering if the mass balance equation would look like this CH3OH+1.75(O2+3.76N2)<---->CO2+1.5H2O+OH+6.58N2 or do we need to solve for all the other species that were mentioned in the question? thank you for your help Answer: To calculate the stoichiometric mixture fraction you need to consider the equation CH3OH + a_st(O2+3.76N2)= bCO2 + cH2O+dN2 OH is not a stable product of complete combustion. For part b the hint regarding no differential diffusion is crucial, it implies that the mass originating from the fuel stream always maintains the same ratio of C:H:O, so that the mass fraction of oxygen atoms from the fuel stream Y_O,fuel is always equal to a (constant) (Y_C, fuel) or (another constant) (Y_H, fuel). Question: Example problem 7.5 on page 245 of Turns states that the local mixture fraction can be determined knowing that it must be proportional to the local elemental H mass fraction since the only source of elemental H within the flame is from the fuel. I am a little confused why this is true. Also, can this be assumed then for problem 3b of homework 4? Answer: If there is no differential diffusion then all molecules that come from the fuel stream will diffuse at the same rate, so for any lump of fluid that contains fuel stream fluid the ratios of the mass fractions of H, C, and fuel stream O will remain the same. After the fluid from the fuel
Image of page 1

Info icon This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Image of page 2
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

What students are saying

  • Left Quote Icon

    As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

    Student Picture

    Kiran Temple University Fox School of Business ‘17, Course Hero Intern

  • Left Quote Icon

    I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

    Student Picture

    Dana University of Pennsylvania ‘17, Course Hero Intern

  • Left Quote Icon

    The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

    Student Picture

    Jill Tulane University ‘16, Course Hero Intern