[urbansound]

Hi,

Thank you for all that CFD Online provides.

I'm a recent member and will be approaching combustion design for can-annular applications with turbocharger prime mover combinations for design testing toward more dedicated turbine development. I expect the efforts will remain among combustion chamber designs with turbine dynamics overlaid to simulations in most cases where mass flow and pressure values can be input across published power band maps etc., not requiring the actual turbo solid models integrated.

I hope to work in gaseous propane at first with alternate testing with methane or even lower heat value gaseous fuels.

The question is where to start for an acceptable but capable software base on a limited budget. The time invested in assembling and learning a given software assembly is one concern for time and effort.

I run an 8 core 4Ghz Intel Core i7 with Nividea GeForce support, 16 G RAM unfortunately saddled with Win 10 as the OS.

I have Autocad 2017 and a copy of Ansys / fluent student version but it comes with a 32K limitation in mesh density and other limitations I question might not be a good choice. I have tried previously to apply Foam but found the complete assembly of Open Source solutions was difficult without some guidance to avoid errors and lack of experience to create a fuller working solution.

I have basic skills in Nix admin but the machine I'm running is a dedicated Win 10 machine so I avoid alternate OS implementations which might create other issues I depend on this machine for.

I am fairly new to CFD modelling after 30 years mechanical engineering so complexity and application learning is also part of what I'm facing to get to a point of functional and reliable design to real world testing.

I would appreciate if others who have taken similar paths to develop their applications and learning approach might share suggestions as to assemble an Open Source solution capable of analyzing combustion metrics and gas phase analysis if this predicates specific software better suited. I assume I will seek further guidance here on the forums as I progress in this need so it seemed only right to ask here among others with similar experience and goals so I not waste other's time to offer guidance from time to time.

Thank you in advance for any suggestions or considerations on the value of choosing capable Open Source approaches.

Regards,

Mike

[arjun]

Originally Posted by urbansound

Hi,

Thank you for all that CFD Online provides.

I'm a recent member and will be approaching combustion design for can-annular applications with turbocharger prime mover combinations for design testing toward more dedicated turbine development. I expect the efforts will remain among combustion chamber designs with turbine dynamics overlaid to simulations in most cases where mass flow and pressure values can be input across published power band maps etc., not requiring the actual turbo solid models integrated.

I hope to work in gaseous propane at first with alternate testing with methane or even lower heat value gaseous fuels.

The question is where to start for an acceptable but capable software base on a limited budget. The time invested in assembling and learning a given software assembly is one concern for time and effort.

I run an 8 core 4Ghz Intel Core i7 with Nividea GeForce support, 16 G RAM unfortunately saddled with Win 10 as the OS.

I have Autocad 2017 and a copy of Ansys / fluent student version but it comes with a 32K limitation in mesh density and other limitations I question might not be a good choice. I have tried previously to apply Foam but found the complete assembly of Open Source solutions was difficult without some guidance to avoid errors and lack of experience to create a fuller working solution.

I have basic skills in Nix admin but the machine I'm running is a dedicated Win 10 machine so I avoid alternate OS implementations which might create other issues I depend on this machine for.

I am fairly new to CFD modelling after 30 years mechanical engineering so complexity and application learning is also part of what I'm facing to get to a point of functional and reliable design to real world testing.

I would appreciate if others who have taken similar paths to develop their applications and learning approach might share suggestions as to assemble an Open Source solution capable of analyzing combustion metrics and gas phase analysis if this predicates specific software better suited. I assume I will seek further guidance here on the forums as I progress in this need so it seemed only right to ask here among others with similar experience and goals so I not waste other's time to offer guidance from time to time.

Thank you in advance for any suggestions or considerations on the value of choosing capable Open Source approaches.

Regards,

Mike

What type of combustion model you wish to use for it.

[urbansound]

Originally Posted by arjun

What type of combustion model you wish to use for it.

Hi,

I may need to move this thread to another more appropriate forum here, but maybe that recommendation might benefit from further detail below.

My efforts are pushing the envelope somewhat on can-annular application for observing scaling with various turbochargers versus chamber dimensions. The losses associated with smaller turbos is of keen interest looking at both propane and methane combustion properties, combustion quality and emissions.

I'm suspect my own ability to harness open source CFD is not suitable, despite having a capable machine, the learning curve in open source such as OpenFoam seems extensive being a novice coder in C or script applications done well, plus my skill set with Nix is not sufficient as well as being stuck for now in Windows 10.

I'm looking at typical 3 zone flame tube applications and trying to find dimensional modeling in spreadsheet or dedicated application or computational numeric in order to identify orifice sizes, zone distances, patterns, annular space values, length, temperature, turbulence, etc.

Modifications such as countersinking perforations, vena-contracta, toroidal turbulence, velocity and penetration are all variable considerations in ignition stability, mixing and gas phase transitions. The effects of scaling in these geometries is both diverse and somewhat relative. Finding a cost effective means to model scaling across fuel versus turbo dynamics, impeller sizes versus flame tube dimensions all come into play as dimensionless formula I'm hoping to find in open source tools to help identify moderate proportional scaling with somewhat reliable values reducing the multiple build effort.

My recent structural design has yielded a 300 PSI capable combustor which permits disassembly in 3 minutes to remove a suspended flame tube mounted between working fit slip rings allowing expansion. This makes the turn around time for FT modification very tollerable. Still, I don't want to waste other's time and effort shooting in the dark on guessing at design alterations. I also don't have much faith in testing the assembly outside of the integrated turbo, which I feel is a bit too rudimentary to resolve these values simply on open atmospheric observations.

Upon finding a more ideal tool set to these calculations, I'm hoping to then submit 3D solid designs to freelance for CFD observation, more cost effectively for myself and less demand on the freelancer's time / effort.

I have completed a rough design and bench testing from prior estimation which suggests a propane combustion model nearing "Flameless" results which is the ultimate goal I'm seeking to move toward in methane without going to a more complex airliner engine type combustor. The problem was my first two combustor approaches ended up too large creating a very narrow powerband which would not stabilize spooling well without quickly blowing the combustion cloud outside of the turbo assuming stall or surge dynamics were encountered operating around the 1.6 P2 pressure ratio range providing some 12 PSI of boost nearing 70% optimal compressor map values on a very small turbo.

Only by coincidence of imperfect seals in early design did I find brief points of sustain (two wrongs kind of ending up right). The result was an incredibly even heat distribution on 90% of the FT length with stainless oxide witness suggesting a survivable FT thermal witness. Boost and spooling were impressive. Response and lag behaviors were incredibly responsive simply not stable to good reproduction or repeatability. The early design was not well optimized for modification turn-around time, frustrating and costly.


If that helps paint the picture, what I'm looking for are spread sheets or applications which work to stabilize some of these variables to permit more reliable scaling toward a common FT dimensional model to consolidate windows of scaling families per FT and OCC modular values.


Thank you for any feedback or recommendations. Hopefully I kept the dialog here sufficiently brief.



Mike