Meeting Minutes and Information

Apr 5, 2009 - Keith Wakeham

Final Report Online here. Model with torque connected here. Constant speed version here. All are in the project area here.

Thats it folks! Engine model completed, writeup done, presentation online. Thanks to everyone!

Apr 3, 2009 - Keith Wakeham

Last meeting with Dr. Hookey occured April first. We showed him the final model plus some simulations. He made some really good suggestions for our presentation which we have implemented. We have compiled data and tested the system by adjusting spark advance, compression ratio, number of valves, sizing of valves and more. The operation is as predicted by many of the books and papers.

Thanks to everyone and the final version is the project area here.

Mar 24, 2009 - Keith Wakeham

It seems a little shameful but everyone's schedule has been exceedingly overloaded. As a result we missed updating for one meeting. The last meeting took place friday March 20th. We showed Dr. Hookey a model that included a valve setup that fully opened instantly and close instantly but it calculated if the flow was choked and chose the appropriate equation. He pointed us to not bothering increasing the usability significantly for others of the model citing that the model was our project and for us to use. Due to time constraints this has been accepted as a limitation.

We are meeting this friday coming with Dr. Hookey and hope to show him a model that includes a frictional calculator included in the model.

FINAL PRESENTATION APRIL 6, 4:00PM in EN 2006

Mar 1, 2009 - Keith Wakeham

No real official team or supervisor meetings have occured recently due to snow storms and midterm break. However work has been proceeding on individual levels. A team disccussion on development of the the burn time lead to several possible attempts at modelling but in the end it is realized that new engines utilize complex swirl which is dependant on valve life, duration, piston shape, combustion chamber shape, piston speed, how the fuel was atomized, etc etc. Withou CFD and more accurate geometery it is impossible to predict what is going on. Approximations based on an equation quoted in several papers referencing Hires et al gives an approximation based on the ratio of engine rpm to a reference to the power of one third. This is where the model will stop in predicting burn duration. The equation is found in this paper as equation 10.

All Models are now posted in project, but only Mark I and Mark II Rev B wiill be documented. In project files here. Ron Spoted that the pressure energy was taking work out of the fluid when it was to be putting work into it since Mark II. Mistake that was overlooked but corrected in latest revision and in Mark II Rev B since the second project report is going to be based on this.

Feb 17, 2009 - Keith Wakeham

Team meeting discussing the next direction to head. The project has fallen onto a stumbling block in regards to combustion. The laminar flame speeds are easy to calculate but are not the prime determining factor for the speed of the flame front. The flame is turbulent and is caused by the gas movement of pumping air into and compressing it. As a result there is limited avenues to proceed. There is a paper on Hydrogen combustion and predicting flame front but there is information that is unable to be determined for certain values (paper here). It seemed like a good avenue but once the team started looking at the detailed equations it was found that there appears to be a typo of sorts of what looks like an omega, a number 1, then a letter e. It is unsure what this means. However modeling a simple spherical burn patterned was decided on in a cylinder. It is likely that the eddy entrainment velocity prescribed in the paper can be used as the burn velocity.

Feb 11, 2009 - Keith Wakeham

Weekly meeting with Dr. Hookey showing very little change to the project. Mark III Revision A was shown to Dr. Hookey and the modifications to the energy calculation for time stepping and using the old temp. Ron working on energy release. The flame front is difficult to predict and Dr. Hookey seems to indicate that we should stop at the Weibe function once we incorporate some way to adjust for engine rotational speed. The next work will be on incorporating exhaust and intake since the combustion analysis would require very accurate CFD. (Ansys Presenation on it here). A simple radial burn model may be built based on simple flame front model with simple geometery. This would be the extent of flame modelling and signal the end of the combustion analysis (once gas composition is intergrated). The rest of the time will focus on the development in other area's and validation.

Feb 4, 2009 - Keith Wakeham

Weekly Meeting with Dr. Hookey. Mark II Rev B model completed just before meeting with very little testing. Rather than using an isentropic or polytropic process it is based on energy input into mass. As it compresses the fluid it adds energy to the system. Internal energy is computed via the idealized Cp *(T2-T1). The new temperature is used to find the pressure using ideal gas law. A weibe function is used to determin how much additional energy is added to the system over what time. This comes surprisingly close to the graphs of Pressure versus Crank angle.

We explained the model to Dr. Hookey who seemed to indicated steps towards exhaust pumping. The accuracy of the combustion model was suggested as the next step and to base either internal energy or Cp on Temperature and composition of the gas. This will lead to a more accurate model. Then pumping losses, heat transfer and other variables can be added onto the model. Dr. Hookey suggested meeting Friday indicating he wants to try using the model over the next couple of days. Mark II Rev B after some clean up is available in project section here.

Jan 28, 2009 - Keith Wakeham

Had our weekly meeting with Dr. Hookey. Showed him the ottocycle connected to the geometry model. He was able to point out that the ottocycle model was definetly working the way it should because as the piston speeds up the crank loss speed was less due to the availability of more stored energy. This is another good point for validation. The next step and method for incorporating the simple heat release model was discussed. It looks like step wise intergration using previous time step values will be necesarry. I was very much hoping to use the continuous functions for the entire project mainly due to how simulink works in the background by time stepping internally but this may not be possible. The team will meet in the next little while to determine the path we need to follow.

Jan 27, 2009 - Keith Wakeham

First working model completed today. May need some small revisions but based on crank geometery, crank interia, intial speed, and combustion temperature it uses the otto cycle model to cauase the crank to speed up during the exhaust stroke, slow down during compression and assume atmospheric for intake and exhaust (no force). This is a great achievement in allowing the team to start working on incorporating the combustion model into the system. The model is available in the Project section here.

Project is now ahead of schedual. Lee is starting to learn the Lotus Engine Simulator for later verification of our model. Ron is pulling together the equations of combustion we need from the Applied Combustion Handbook. Mini report is being compiled for Monday consistenting of mainly our background and the simple otto cycle model.

Jan 22, 2009 - Keith Wakeham

Met today shortly to discuss progress of the project. It seems that the pressure model is off course slighly and doesn't make sense. This is a planning oversight combined with some lack of understanding. I've taken the simple heat release model and going to look at it during the weekend to see what it is doing while having Tang work on a simpler model. Ron and Lee are still working on background. I've asked Lee to be support for Tang if needed. There seems to be a loss of understanding in this project of what we are building from.

Jan 20, 2009 - Keith Wakeham

Presentation went well, thank goes out to the team and all the great questions we recieved. Some really challenging ones and I hope that we will have the answers well documented and explained in our final document.

New gantt chart up on in the project area as well as a simple crank resolver using continous function intergration. Based on eqauations from Heywood.

Ron still reading on combustion, Tang is working on getting the ottocycle / simple heat release to work with my crank resolver.

Jan 19, 2009 - Keith Wakeham

Met for rehersal of the presentation for the 20th. Made some modifications. Length seems good. Lee took Design and Simulation book to get more familar with the engine models and I took Internal Combustion Engine Fundamentals from Tang by John B. Heywood which is the primary reference document for the lotus engine simulator.

Jan 18, 2009 - Keith Wakeham

Reading some in the book Design and Simulation of Four-Stroke Engines by Gordon P. Blair. It has been a good resource but there is difficulties in extracting his very detailed model. It is divided over four chapters but in a poorly organized fashion. The Presentation has had a couple of updates, mainly two pages added on Simulink and the Model. Very little could be added to Combustion at this time since we are still trying to disect it. It is the main part of this project and we are having difficulties relating what we want to know to what is in front of us.

Jan 17, 2009 - Keith Wakeham

Worked on Presentation and Gantt chart. Presentaion is located here or can be downloaded on the Project Page here. Gantt chart still a new work in progress which will strip unnecessary items out of the project. Team members review the presentation and get back to me ASAP.

Jan 16, 2009 - Keith Wakeham

Team meeting today to discuss the initial model and plan the project a little better. Tang metioned he has some things he wanted to talk about for creating a model based on the introductory theory that extends the ottocycle in the book Internal Combustion Engines by Ferguson and Kirkpatrick. The theory takes the otto cycle and adds a simple finite heat release mechanism based on crank angle. Tang is to work on this over the weekend. I gave a paper to Ron called Hydrogen-Oxygen Reaction Mechanism and Its Implication to the Hydrogen Engine Combustion by L. M. DAS. He's started going over it and has found some information pertaining to reactions combustion ignition. He's working on going over it in detail as well as looking at a book.

Initially Lee was working on the modelling and understanding, Tang on Simulink, Ron on combustion, and myself was trying to keep hands off a little a be a better manager. Lee is stronger in programming and moving from concept to software so suggested we reorganize a little. I have some background in the modelling so I am taking that over along with being admin but will likely outsource some of that to the team now, Lee will move to bridge the gap of theory to computer model and Tang and Ron are still on Simulink and combustion respectively.

Gantt chart and mini presentation for Tuesday is to be completed by the 17th for initial review.

Jan 15, 2009 - Keith Wakeham

Met with Dr. Hookey this morning. Scheduled meetings to occur Wednesday morning at 8:00am weekly. Gantt chart needs to be updated again due to recommendations. Main focus was on expanding out the model from the simple one. Main thing is to get the simplest one working in simulink and keep expanding like orignally suggested but his suggestion is to keep the scope small and to be realistic in terms of other course loads. The model should incorporate the chemistry of hydrogen combustion which should be added to the simple heat release model. An underlying issue which Dr. Hookey seemed to focus on but not bring forward directly is the logistics of keeping everything organized and everyone communicating.

Jan 14, 2009 - Keith Wakeham

Adjusted Gantt chart for the new plan. Available in the project section here

Jan 12, 2009 - Keith Wakeham

Team met to discuss plans on developing model. Plan is to start from a very basic model and work outwards. Idea is ottocycle, simple heat release, pumping loss, bearing losses, cam losses, chemistry model for gasoline, then replace with hydrogen. Project looks rather large

Pre Jan 12, 2009 - Keith Wakeham

Small amount of communication between team. Some links and papers were sent out and suggestions of what everyone should be researching. Unrealistic expectations on the amount of work that was hoped to be completed, and therefore not nearly as far as expected. Gantt chart needs to be reworked.