[Torque_Converter]

What would you do if your manager (head of analysis dept.) who has no analysis background, just a BSME and MBA, asked you to produce results where no boundary condition is supplied and in a very short time period by using methods that can produce answers of 3 different orders of magnitude based on various wild assumptions? Basically I have to analyze a new device, but all I know about the old device is it produced X torque. This allows me to input an infinite number of boundary conditions and get said torque. Are they right, no of course not. Or I can reduce it to one boundary condition and keep moving till that matches torque, then use it as an assumption in a new design. Due to cost and time to just get it out the door, he doesn't want to take the time to do test or give me the boundary conditions nor the computational power to speed it up to hit schedule. It feels dishonest and wrong, especially since I know its completely against fluid physics (dirichlet and neuman boundary conditions mostly) and CFD best practices.

[Patrick1]

Originally Posted by Torque_Converter

What would you do if your manager (head of analysis dept.) who has no analysis background, just a BSME and MBA, asked you to produce results where no boundary condition is supplied and in a very short time period by using methods that can produce answers of 3 different orders of magnitude based on various wild assumptions? Basically I have to analyze a new device, but all I know about the old device is it produced X torque. This allows me to input an infinite number of boundary conditions and get said torque. Are they right, no of course not. Or I can reduce it to one boundary condition and keep moving till that matches torque, then use it as an assumption in a new design. Due to cost and time to just get it out the door, he doesn't want to take the time to do test or give me the boundary conditions nor the computational power to speed it up to hit schedule. It feels dishonest and wrong, especially since I know its completely against fluid physics (dirichlet and neuman boundary conditions mostly) and CFD best practices.

If he doesn't care about the accuracy of the results or how you get them, just tell him to draw whatever graphs he needs by himself in Excel without doing simulations at all. Like you say, the simulations will be worthless anyway, might as well not do them.

He is basically asking you to lie for him. If the false results get found out, you will get the blame because the results came from you. He will not be guilty because he can just say that he doesn't understand what was going on and that you're the expert!

[Torque_Converter]

The unfortunate result will be me being fired, as the previous two CFD engineers were fired, supposedly, for being too negative and saying things can't be done.

[Patrick1]

Originally Posted by Torque_Converter

The unfortunate result will be me being fired, as the previous two CFD engineers were fired, supposedly, for being too negative and saying things can't be done.

Well why are they employing CFD engineers if they don't care about the accuracy of results in the first place lol? Lie to keep your job but I'd try and move somewhere else that will let you do your job properly without being fired!

[Torque_Converter]

I think they got me so that they can get good answers but still provide garbage input. I guess they don't know garbage in=garbage out. They seem to think they don't even need to provide me with boundary conditions for them to get usable answers! Unfortunately, since they paid to move me out here I'm stuck for 2 years, so I guess that's 2 years of fudging data and hoping nothing fails in prototype testing too badly.

[Patrick1]

Originally Posted by Torque_Converter

I think they got me so that they can get good answers but still provide garbage input. I guess they don't know garbage in=garbage out. They seem to think they don't even need to provide me with boundary conditions for them to get usable answers! Unfortunately, since they paid to move me out here I'm stuck for 2 years, so I guess that's 2 years of fudging data and hoping nothing fails in prototype testing too badly.

Maybe explain to them that they need to give you good BCs to get decent results. Or maybe they will understand themselves when everything goes wrong in testing.

[rwryne]

If they(management) are at all resistant to listening to you explain this problem, you should probably start working on the resume... Problems like this are indicitative of a deeper seeded issue.

[Torque_Converter]

You are 100% right. I have explained in very simple terms things like boundary conditions, dirichlet and neuman. I've even challenged them to solve a single equation with 2 unknowns to demonstrate on a simple level what they want me to do. They don't believe me, perhaps because I am the only fluid/thermal analyst here, perhaps because they dont want to. I am stuck thou for at least 2 years since they paid for my move and if I leave before then I've got about a 15,000 dollar bill!

[Patrick1]

Originally Posted by Torque_Converter

You are 100% right. I have explained in very simple terms things like boundary conditions, dirichlet and neuman. I've even challenged them to solve a single equation with 2 unknowns to demonstrate on a simple level what they want me to do. They don't believe me, perhaps because I am the only fluid/thermal analyst here, perhaps because they dont want to. I am stuck thou for at least 2 years since they paid for my move and if I leave before then I've got about a 15,000 dollar bill!

Is it worth getting yourself sacked then?

[rwryne]

Originally Posted by Torque_Converter

You are 100% right. I have explained in very simple terms things like boundary conditions, dirichlet and neuman. I've even challenged them to solve a single equation with 2 unknowns to demonstrate on a simple level what they want me to do. They don't believe me, perhaps because I am the only fluid/thermal analyst here, perhaps because they dont want to. I am stuck thou for at least 2 years since they paid for my move and if I leave before then I've got about a 15,000 dollar bill!

I am sure you could get out of that bill with the proper legal support....asking you to do something immoral and dishonest has to break an agreement/law/ethics code somewhere.

[JBeilke]

Originally Posted by Torque_Converter

I have explained in very simple terms things like boundary conditions, dirichlet and neuman.

That's probably not a very simple explanation. Are you an engineer?

If there are two torque converters (old and new), there should be a simple way defining a test setup. Ask the people who do the experiments, what they are measuring.

[Torque_Converter]

I am a physicist turned engineer, he is unfortunately the type who finishes engineering school then goes straight to management. If he is going to discuss fluid dynamics with me he should have these basic understandings, or look them up.

For this case it is a retarder. There is a mass flow of fluid in and an outlet that is at some pressure. As the mass flow increases the torque capacity increases and the outlet pressure changes. The proper way to do this would be to have either measurements of the mass flow and pressure out or data from the geometry and pump outside the retarder. He says this is not possible (haha) or that it isn't necessary information to solve it, so just solve without it however its possible even if we have to force fit to data.

[JBeilke]

Originally Posted by Torque_Converter

I am a physicist turned engineer

It sounds like that.

Originally Posted by Torque_Converter

If he is going to discuss fluid dynamics with me he should have these basic understandings, or look them up.

But he is your boss. He might even tell you to clean the restrooms or listen to vogon poetry.

Originally Posted by Torque_Converter

For this case it is a retarder. There is a mass flow of fluid in and an outlet that is at some pressure. As the mass flow increases the torque capacity increases and the outlet pressure changes. The proper way to do this would be to have either measurements of the mass flow and pressure out or data from the geometry and pump outside the retarder.

Welcome to the real world of engineering. Most of the time things are imperfect, data are missing or confusing and you have to be clever to survive.

Just look at the characteristic curves of similar devices and choose some points for a calculation.

[Torque_Converter]

If you have anything of value to add, then please. Otherwise, refrain from implicit insults about my education and background. It's not unreasonable that the head of an analysis group should have a basic understand of the work of his analysts, especially if he is going to insert himself into the issue.

[julien.decharentenay]

Hi,
From reading your posts, you have no choice but to stay there for 2 years (unless you find another employer willing to fork out the $15,000).
In the meantime, you probably want to get things in writing to cover your ass. As a tip, if your boss does not want to put in writing, you can send him an email that summarising the verbal discussion (just to confirm).
And try to do some clever guessing of boundary conditions.
Julien

[Torque_Converter]

Thanks Julien, I haven't been doing that lately, but email exchanges archived seem like the perfect idea. I can then always show that he explicitly told me to massage data to match test even if it involves unphysical boundary conditions.