Ben - thank you .. this was the kind of feedback I was looking for.
K
On Sep 16, 2015, at 9:36 AM, Ben Brockert <wikkit@xxxxxxxxx> wrote:
For the regen passage roughness can be a design improvement. For the
inside of the chamber it's not helpful, but it's relatively easy to
post machine or polish that.
I'm more curious if they're using standard channels or if they're
using a more modern design appropriate for a printed engine. I'm
always a bit frustrated when I see 3d printed engines with channels
that were designed for a milled chamber. At least spiral them enough
that differences in flow from channel to channel don't cause linear
hot spots and early failures.
Re Rocketlabs in particular, I've talked with people who have visited
their facility in NZ and saw a live engine test. It sounds like they
have a good grasp on what they're doing.
Ben
On Wed, Sep 16, 2015 at 12:14 PM, Ed LeBouthillier
<codemonky@xxxxxxxxxxxxx> wrote:
The question was honestly asked .. I am not a liquid motor specialist … and
was genuinely curious about whether their approach of 3D printing the motor
introduced even more risk.
Although 3D printing seems to simplify some things, I too wonder about
complications due to its use.
One issue that interests me is the effects of surface texture due to 3D
printing.
I know that different surface textures can affect the heat transfer rate. My
understanding is that surface texture affects boundary layer formation. The
surface texture from their 3D printing looks rough and I'm curious as to
whether that would be a help or hindrance. Perhaps it's just something that
has to be accommodated in the design.
Anyone else out there have any idea about the effects of surface roughness
on cooling in an application like this?
