RE: [Vo]:Manifold mispositioning makes measurements meaningless

2011-10-27 Thread Higgins Bob-CBH003
This is a lot of good work, Alan. I am amazed at the number of high quality posts on Vortex. I am having trouble keeping up because each post warrants a good deal of thought. I examined pictures of the manifold and created a diagram to capture the important features. [I made a small .png

Re: [Vo]:Manifold mispositioning makes measurements meaningless

2011-10-26 Thread David Roberson
Maybe you have an error with your simulation since the number does not seem to match the real world results. What kind of flow did you assume in the primary? I think that vapor condensation is where the most action is since that takes so much more energy than cooling the hot condensed

Re: [Vo]:Manifold mispositioning makes measurements meaningless

2011-10-26 Thread Alan J Fletcher
At 03:55 PM 10/26/2011, David Roberson wrote: Maybe you have an error with your simulation since the number does not seem to match the real world results. What kind of flow did you assume in the primary? I think that vapor condensation is where the most action is since that takes so much more

Re: [Vo]:Manifold mispositioning makes measurements meaningless

2011-10-26 Thread David Roberson
To: vortex-l vortex-l@eskimo.com; vortex-l vortex-l@eskimo.com Sent: Wed, Oct 26, 2011 7:06 pm Subject: Re: [Vo]:Manifold mispositioning makes measurements meaningless At 03:55 PM 10/26/2011, David Roberson wrote: Maybe you have an error with your simulation since the number does not seem to match

Re: [Vo]:Manifold mispositioning makes measurements meaningless

2011-10-26 Thread Alan J Fletcher
http://www.engineeringtoolbox.com/overall-heat-transfer-coefficients-d_284.html water-copper-air is 13.1 (W/m2 K) steam-copper-air is 17 And for flowing water/steam, I think that the MASS flow is what counts, not the volume flow, so there isn't a big transferdifference between the two.

Re: [Vo]:Manifold mispositioning makes measurements meaningless

2011-10-26 Thread Daniel Rocha
There is a problem with you simulation, in my opinion. The number of cells in your model increases linearly with the distance from the flow. But it increases linearly because your model is 2D. If it were a 3D model, the number of cells would increase by the square of the distance, and the

Re: [Vo]:Manifold mispositioning makes measurements meaningless

2011-10-26 Thread David Roberson
am sure you can get it resolved. -Original Message- From: Alan J Fletcher a...@well.com To: vortex-l vortex-l@eskimo.com Sent: Wed, Oct 26, 2011 7:26 pm Subject: Re: [Vo]:Manifold mispositioning makes measurements meaningless http://www.engineeringtoolbox.com/overall-heat-transfer

Re: [Vo]:Manifold mispositioning makes measurements meaningless

2011-10-26 Thread Alan J Fletcher
At 04:44 PM 10/26/2011, Daniel Rocha wrote: There is a problem with you simulation, in my opinion. The number of cells in your model increases linearly with the distance from the flow. But it increases linearly because your model is 2D. If it were a 3D model, the number of cells would increase

Re: [Vo]:Manifold mispositioning makes measurements meaningless

2011-10-26 Thread Alan J Fletcher
At 04:48 PM 10/26/2011, David Roberson wrote: I was referring to the fact that the steam is condensing and not just loosing heat slowly along the entire distance. The manifold section of pipe is very short compared to the length of the hose from the eCat, and the (effective) length inside the

Re: [Vo]:Manifold mispositioning makes measurements meaningless

2011-10-26 Thread Daniel Rocha
Well, are you sure? If you see the object in 3D, the object is not symmetrical, so, it is not a matter of just increasing the radial value. 2011/10/26 Alan J Fletcher a...@well.com At 04:44 PM 10/26/2011, Daniel Rocha wrote: There is a problem with you simulation, in my opinion. The number of