Jump to content

Sign in to follow this  
Ray_the_pilot

N1 vs EPR?

Recommended Posts

Hi,I have mostly, also while flying the -400F, used GE powered engines which uses N1 for power reference. Now I have tested out the PW and RR powered aircraft, but find it difficult to understand the EPR reference on the EICAS. I also find it difficult to find any information about it. So I just wonder, can anyone tell me the difference between using N1 and EPR as a reference. I know that N1 is the power of the large fan in the front of the engine, but what does EPR represent? What do the numbers on the EICAS mean?RaymondNorway


Raymond Bergseng ENGM

________________________________

 

Asus P6T WS Professional, Intel Core i7 980X 3.33GHz (OC to 3.8), Zalman CNPS9700 NT CPU cooler, 12 GB OCZ Platinum XTC DDR3 1600MHz, EVGA GeForce GTX 580 "Superclocked Edition" 797MHz 1536MB, M-Audio Fast Track Ultra external USB soundcard, WD VelociRaptor 300GB SATA discs, Cooler Master Stacker nVidia Edition w/850W PSU, Dell UltraSharp 24" LCD, Windows 7 Ultimate x64, Logitech Ultra X Premium Keyboard, MX 518, Saitek Yoke and Rudder.

Share this post


Link to post

EPR: Engine Pressure Ratio is the ratio of inlet vs exhaust pressure or a common turbojet measure of roughly how much power is generated. This same subject was discussed in some detail earlier, perhaps a search of the forum would help. N1 is no exactly the measure of power, simply RPM; whereas the EPR can be visualized as more more direct measure of power. Both N1 and EPR have limits, it is usually only one that is limiting depending on temperature and altitude.


Dan Downs KCRP

Share this post


Link to post

Ahh...I get it. So the numbers on the EPR in EICAS is the actual ratio of inlet vs exhaust, right?I tried to search the PMDG forum, but I got up so many hits that didn't help me at all, that I decided to ask instead. I'll try to do a more thorough search. Thank you for your help.RaymondNorway


Raymond Bergseng ENGM

________________________________

 

Asus P6T WS Professional, Intel Core i7 980X 3.33GHz (OC to 3.8), Zalman CNPS9700 NT CPU cooler, 12 GB OCZ Platinum XTC DDR3 1600MHz, EVGA GeForce GTX 580 "Superclocked Edition" 797MHz 1536MB, M-Audio Fast Track Ultra external USB soundcard, WD VelociRaptor 300GB SATA discs, Cooler Master Stacker nVidia Edition w/850W PSU, Dell UltraSharp 24" LCD, Windows 7 Ultimate x64, Logitech Ultra X Premium Keyboard, MX 518, Saitek Yoke and Rudder.

Share this post


Link to post

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
Sign in to follow this  
  • Tom Allensworth,
    Founder of AVSIM Online


  • Flight Simulation's Premier Resource!

    AVSIM is a free service to the flight simulation community. AVSIM is staffed completely by volunteers and all funds donated to AVSIM go directly back to supporting the community. Your donation here helps to pay our bandwidth costs, emergency funding, and other general costs that crop up from time to time. Thank you for your support!

    Click here for more information and to see all donations year to date.
  • Donation Goals

    AVSIM's 2020 Fundraising Goal

    Donate to our annual general fundraising goal. This donation keeps our doors open and providing you service 24 x 7 x 365. Your donation here helps to pay our bandwidth costs, emergency funding, and other general costs that crop up from time to time. We reset this goal every new year for the following year's goal.


    2%
    $640.00 of $25,000.00 Donate Now
×
×
  • Create New...