For amateurs a much much lower chamber pressure is more likely. There are
some good graphs online of Isp vs Chamber pressure and at some point the
marginal gains are not worth the engineering time and money spent on a
higher pressure pump.
I have been curious about different pumping mechanisms. Instead of a turbo
pump what about positive displacement pumps, like gear or lobe? Has there
been any attempt at using one of these types of pumps?
On Thu, Dec 15, 2016 at 10:07 AM, Graham Sortino <
dmarc-noreply@xxxxxxxxxxxxx> wrote:
Hi Peter-
Thanks a lot for the updates. I've pasted a few comments below to your
inquires.
As a somewhat related aside, I'm somewhat confused by Rocketlab's electric
pump. They claim they are using a single 50 HP motor @ 40k RPM's
http://aviationweek.com/space/rocket-lab-unveils-battery-
powered-turbomachinery
...but given the rough calculations I've done that seems like not enough
power to get a really high pressure chamber pressure. I should note though
that I haven't seen them publish their actual chamber pressure but I did a
bit of rough calculations and estimated it to be about 2200 psia.
All the Best,
Graham
On Wednesday, December 14, 2016, 12:49:11 PM EST, <cnc-engineering@xxxxxx>
wrote:
Hi Graham,
good to know, that you are involved in current activities !
- I agree, that two motors could be used in one pump application, in case
power of a single unit won't be sufficient. (Rocket Lab is doing the same,
i.e. using one pump for LOX and Kerosene each.)
a pump you could use 2 30kW motors to power a single shaftActually, what I meant is that if you needed for example 60 kW to power
=> do you have any other idea where to look for high-power / high-RPM
motors ?
small DC brushless motors.Not much higher than that. 30 kW seems to be about the maximum for
Please keep us updated concerning your progress !
Will do!
Best,
Peter
