X-CGP-ClamAV-Result: CLEAN X-VirusScanner: Niversoft's CGPClamav Helper v1.23.0 (ClamAV engine v0.103.0) X-Junk-Score: 0 [] X-KAS-Score: 0 [] From: "Stephen Izett stephen.izett@gmail.com" Received: from mail-pj1-f46.google.com ([209.85.216.46] verified) by logan.com (CommuniGate Pro SMTP 6.3.5) with ESMTPS id 40102 for flyrotary@lancaironline.net; Sun, 23 May 2021 20:24:11 -0400 Received-SPF: pass receiver=logan.com; client-ip=209.85.216.46; envelope-from=stephen.izett@gmail.com Received: by mail-pj1-f46.google.com with SMTP id kr9so5765746pjb.5 for ; Sun, 23 May 2021 17:24:11 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:mime-version:subject:date:references:to:in-reply-to:message-id; bh=FzkSCdr9NhdjzzumugGjCRdjcSh0KnadDb14n6CxIOM=; b=B5eyNcs/9Faoru/bcRKQrFTzDNEYDmmdLWDFdu/YEnLS6kJShMQH1JvnM3B6JdW3mh gPksp7qw1ZP8N4aoY9JmXharxYzMkd4kuxxOGZMqZnh2xTspIllVnNlMu8+X2vLikbFl x7Z37VClqR1agtdHtzvaleNPPPQ6BxS4ETgckKPilouVxC0VXxkEg6XrVNfKwkMbrM+A fcraMkjtgG0Ye86RSGKYHL2+7utdIggWcA3ttp/qVtS4f6h6BzgCMSAhk92D7HFxVSXV XUhK9Xugl+39JKOvMMgdrXJZ8oMbb5XETLSuxXwTF5gpEppjv/jGnLxbnQpKRJi5pYfL q+BQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:mime-version:subject:date:references:to :in-reply-to:message-id; bh=FzkSCdr9NhdjzzumugGjCRdjcSh0KnadDb14n6CxIOM=; b=ppqFclykqVx8v5+snGTwFYYyQy9nVNSdrZ5BY4PmQwE0ZZHjW+OcwEpPMlLCgsDTWn 0pnO2xE7IROFtLHASg4CKsORnqaEnhNo2kzRR79swJkSewDmihslMmlgcPPHa58N0kaG OT5Nmx55Uh4Hfb6a4NT5u2FXeeJp9lGAoRYHmPUPiHoeVDfV16MgGbQVaAQCdtW7KW4A cAne43zOoadZKqoq9JDMTDct8FeKEaLDOM1mdRrUCoXsS2hfOeruOMXI/vZywH8om1JR 9DF2P+yknCHYLb9MnKp8Xm7l0h7H4E02wTsYSaBY/WyUTjS+H9gB7WO1qnSWCWBIp5T+ NRxQ== X-Gm-Message-State: AOAM531qMn3aiO0w/CZhn3m3raMoNWlKE7VSvV18d6cDHZ5ypUa/di4y amU2YRCfY9R9+iwDufr/3gxEie+FSw8= X-Google-Smtp-Source: ABdhPJyJAVSV4TSx8bKpWz+mThJEKJ7WtpY1K0UQS5fTQM2D/DkjjT+7m45gCfIYRDk5kwFtkm4m7w== X-Received: by 2002:a17:902:778d:b029:ee:f821:f56d with SMTP id o13-20020a170902778db02900eef821f56dmr22804826pll.79.1621815833652; Sun, 23 May 2021 17:23:53 -0700 (PDT) Return-Path: Received: from smtpclient.apple (220-235-95-91.dyn.iinet.net.au. [220.235.95.91]) by smtp.gmail.com with ESMTPSA id m5sm9446611pgl.75.2021.05.23.17.23.51 for (version=TLS1_2 cipher=ECDHE-ECDSA-AES128-GCM-SHA256 bits=128/128); Sun, 23 May 2021 17:23:53 -0700 (PDT) Content-Type: multipart/alternative; boundary="Apple-Mail=_7C3ACF43-48BE-4AA0-9183-81049B5530C2" Mime-Version: 1.0 (Mac OS X Mail 14.0 \(3654.80.0.2.43\)) Subject: Re: [FlyRotary] PSRU oil pressure Date: Mon, 24 May 2021 08:23:48 +0800 References: To: Rotary motors in aircraft In-Reply-To: Message-Id: <5114F9A7-71CE-4032-8D43-599F4315947A@gmail.com> X-Mailer: Apple Mail (2.3654.80.0.2.43) --Apple-Mail=_7C3ACF43-48BE-4AA0-9183-81049B5530C2 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset=utf-8 Hi Matt=20 I wouldn=E2=80=99t imagine pressure is a contributing factor, however = the quantity of oil and churning losses generates heat. I found this study - "Experimental Investigations on Churning Power = Losses Generated in a Planetary Gear Set" = https://www.researchgate.net/publication/321990749_Experimental_Investigat= ions_on_Churning_Power_Losses_Generated_in_a_Planetary_Gear_Set This study references the following further studies below: Is there SIGNIFICANT power loss or heat generation that can be easily = rectified by enlarging the drain and adding a breather? Could someone read summarise and present a conclusion =F0=9F=98=80 I=E2=80=99m guessing Steve B has already done this work. Steve, were you interested in losses and heat generation, or seal = problems associated with pressurisation, or both? Cheers Steve Izett Anderson, N.E., Loewenthal, S.H., Black, J.D., An analytical method to = predict efficiency of aircraft gearboxes, NASA TM-83716, USAAVSCOM TR = 84-C-8, (1984). Boness, R.J., Churning losses of discs and gears running partially = submerged in oil, Proceedings of ASME International Power Transmission = Gearing Conference 1989, (1989) 355-359. Changenet, C., Velex, P., A model for the prediction of churning losses = in geared transmissions =E2=80=93 preliminary results, J. Mechanical = Design, 129, 1 (2007) 128-133. Changenet, C., Leprince, G., Ville, F., Velex, P., A note on flow = regimes and churning loss modeling, J. Mechanical Design, 133, 12 (2011) = 5p. Durand de Gevigney, J., Ville, F., Changenet, C., Velex, P., Tooth = friction losses in internal gears: analytical formulation and = applications to planetary gears, Proc. IMechE Part J: J. Engineering = Tribology, 225, 5 (2013a) 476-485. Durand de Gevigney, J., Changenet, C., Ville, F., Velex, P., = Becquerelle, S., Experimental investigation on no-load dependent power = losses in a planetary gear set, Proceedings of International Conference = on Gears 2013, (2013b) 1101-1112. Ho=CC=88hn, B.R., Michaelis, K., Vo=CC=88llmer, T., Thermal rating of = gear drives: balance between power loss and heat dissipation, American = Gear Manufacturers Association Document, 96FTM8, (1996). Kahraman, A., Hilty, D.R., Singh, A., An experimental study of spin = power losses of planetary gear sets, Proceedings of International Gear = Conference 2014, (2014) Kolekar, A., Anant, S., et al., Windage and Churning Effects in Dipped = Lubrication, Journal of Tribology 136.2: 021801, (2014) Krantz, T.L., Experimental and analytical evaluation of efficiency of = helicopter planetary stage, NASA TP-3063, AVSCOM TR 90-C-001, (1990). Luke, P., Olver, A., A study of churning losses in dip-lubricated spur = gears, Proc. IMechE Part G: J. Aerospace Engineering, 213, (1999) = 337-346. Macmillan, R.H., Power flow and loss in differential mechanisms, J. = Mechanical Engineering Science, 3, 1 (1961) 37- 41. Pennestri, E., Freudenstein, F., The mechanical efficiency of epicyclic = gear trains, J. Mechanical Design, 115, 3 (1993) 645-651. Radzimovsky, E.I., How to find efficiency, speed, and power in planetary = gear drives, Machine Design, 11, (1959) 144- 153. Terekhov, A.S., Hydraulic losses in gearboxes with oil immersion, = Vestnik Mashinostroeniya, 55, 5 (1975) 13-17. Velex, P., Becquerelle, = S., Analysis of no-load dependent power losses in a planetary gear train = by using thermal network method, Proceedings of International Gear Conference 2014, (2014), = 615-624.=20 > On 24 May 2021, at 4:53 am, Matt Boiteau mattboiteau@gmail.com = wrote: >=20 > I've always had a crankcase breather filter on the engine, but while I = was testing I wanted to see what kind of actual pressures were developed = inside the system. It was more a FYI. >=20 > I guess in my subject I should have clearly stated this is Neils PSRU = design. Waiting for Neil to chime in on the difference between his and = Tracy's PSRU, but the prop shaft bearings ride on Tapered Roller = Bearings. The oil inlet is on the front half with 1/4npt return on the = side. There is also a 3/8npt return on the bottom of the rear section. >=20 > My whole post was basically saying, gravity return isn't enough. The = psru still gets pressurized even with the smallest of restriction. = Putting a vent line on top, turns into another pressured outlet for the = oil to return. Still, a vent line on top I'd recommend to help the = returns. >=20 > I have a temperature prob in the PSRU. I could be wrong, but having = the psru gears pressurized would cause more heat? I'll see what the = datas shows. >=20 > - Matt Boiteau >=20 >=20 > On Sat, May 22, 2021 at 12:10 AM David Leonard wdleonard@gmail.com = > wrote: > Ok, Here is my third comment. Yes you should absolutely vent your = crankcase. In addition to the stock vent located on the oil filler = neck, I also eventually installed an additional 1/2 in. vent. Both of = these lines go through an oil/air separator which is vented in the low = pressure slipstream and drained out the gear leg. And still it is not = perfect, but improved since the early hours. >=20 > As an aside, I can tell you that increased blow-by is usually the = first indication that I am due for an engine rebuild (among several = other more imminent indications like a sudden loss of power). I = recommend keeping track of blow-by (how much oil is caught by the oil = air separator). If you start getting a lot of oil in the can, you will = need a rebuild soon. >=20 > Dave Leonard > Turbo Rotary RV-6 >=20 >=20 > On Fri, May 21, 2021 at 6:19 AM Matt Boiteau mattboiteau@gmail.com = > wrote: > I played around the past few days with oil and psru. I added a psi = gauge on top of psru,and vented the housing back to the oil dipstick = tube. I have an oil breather tube from the fill port. We should have a = vent on the oil crankcase. Without it, I did a pull and turned off the = engine and 5psi stayed within the system until I cracked open the = dipstick to relieve the pressure. >=20 > On Neil's PSRU, the oil inlet is on the front half. The front drain is = on the side, which connects to the back drain that is an10, then to the = oil pan. >=20 > Anyways, the stock psru inlet restrictor was 9/64. Once warmed up and = running at 2200rpm static on the ground, engine oil is about 100psi for = me. PSRU pressure was about 2.5psi and lots of oil was venting back into = the oil dipstick tube. I kept on sizing down the restrictor until = 1/16th. That mostly kept the vent clean and clear of any pressure build = up inside the psru. >=20 > I'm not sure why Tracy recommends having the psru fuel of oil, maybe = uses different bearings then Neil's? =46rom a truck gear case = perspective, plantey gears only need a coating of oil, not full and = pressurized. I'm probably wrong, but throwing it out there. ?.? >=20 > - Matt Boiteau > -- > Homepage: http://www.flyrotary.com/ > Archive and UnSub: = http://mail.lancaironline.net:81/lists/flyrotary/List.html = --Apple-Mail=_7C3ACF43-48BE-4AA0-9183-81049B5530C2 Content-Transfer-Encoding: quoted-printable Content-Type: text/html; charset=utf-8 Hi = Matt 

I = wouldn=E2=80=99t imagine pressure is a contributing factor, however the = quantity of oil and churning losses generates heat.
I= found this study - "Experimental Investigations on Churning Power Losses = Generated in a Planetary Gear Set" https://www.researchgate.net/publication/321990749_Experimental= _Investigations_on_Churning_Power_Losses_Generated_in_a_Planetary_Gear_Set=

This = study references the following further studies below:
Is there SIGNIFICANT power loss or heat = generation that can be easily rectified by enlarging the drain and = adding a breather?
Could someone read summarise and = present a conclusion =F0=9F=98=80

I=E2=80=99m guessing Steve B has = already done this work.
Steve, were you interested = in losses and heat generation, or seal problems associated with = pressurisation, or both?

Cheers

Steve Izett
=09 =09 =09

Anderson, N.E., Loewenthal, S.H., Black, J.D., An analytical = method to predict efficiency of aircraft gearboxes, NASA TM-83716, USAAVSCOM TR 84-C-8, (1984).

Boness, R.J., Churning = losses of discs and gears running partially submerged in oil, = Proceedings of ASME International Power Transmission Gearing Conference 1989, (1989) 355-359.

Changenet, C., Velex, P., A = model for the prediction of churning losses in geared transmissions =E2=80= =93 preliminary results, J. Mechanical Design, 129, 1 (2007) 128-133.

Changenet, C., Leprince, = G., Ville, F., Velex, P., A note on flow regimes and churning loss = modeling, J. Mechanical Design, 133, 12 (2011) 5p.

Durand de Gevigney, J., = Ville, F., Changenet, C., Velex, P., Tooth friction losses in internal = gears: analytical formulation and applications to planetary gears, Proc. IMechE Part J: J. Engineering = Tribology, 225, 5 (2013a) 476-485.

Durand de Gevigney, J., = Changenet, C., Ville, F., Velex, P., Becquerelle, S., Experimental = investigation on no-load dependent power losses in a planetary gear set, Proceedings of = International Conference on Gears 2013, (2013b) 1101-1112.

Ho=CC=88hn, B.R., = Michaelis, K., Vo=CC=88llmer, T., Thermal rating of gear drives: balance = between power loss and heat dissipation, American Gear Manufacturers Association Document, 96FTM8, (1996).

Kahraman, A., Hilty, D.R., = Singh, A., An experimental study of spin power losses of planetary gear = sets, Proceedings of International Gear Conference 2014, (2014)

Kolekar, A., Anant, S., et = al., Windage and Churning Effects in Dipped Lubrication, Journal of = Tribology 136.2: 021801, (2014)

Krantz, T.L., Experimental = and analytical evaluation of efficiency of helicopter planetary stage, = NASA TP-3063, AVSCOM TR 90-C-001, (1990).

Luke, P., Olver, A., A = study of churning losses in dip-lubricated spur gears, Proc. IMechE Part = G: J. Aerospace Engineering, 213, (1999) 337-346.

Macmillan, R.H., Power flow = and loss in differential mechanisms, J. Mechanical Engineering Science, = 3, 1 (1961) 37- 41.

Pennestri, E., = Freudenstein, F., The mechanical efficiency of epicyclic gear trains, J. = Mechanical Design, 115, 3 (1993) 645-651.

Radzimovsky, E.I., How to = find efficiency, speed, and power in planetary gear drives, Machine = Design, 11, (1959) 144- 153.

Terekhov, A.S., Hydraulic = losses in gearboxes with oil immersion, Vestnik Mashinostroeniya, 55, 5 = (1975) 13-17. Velex, P., Becquerelle, S., Analysis of no-load dependent power losses = in a planetary gear train by using thermal network

method, Proceedings of = International Gear Conference 2014, (2014), 615-624. 

On 24 May 2021, at 4:53 am, Matt Boiteau mattboiteau@gmail.com= <flyrotary@lancaironline.net> wrote:

I've always had a crankcase breather filter on the engine, = but while I was testing I wanted to see what kind of actual pressures = were developed inside the system. It was more a FYI.

I guess in my subject I should have = clearly stated this is Neils PSRU design. Waiting for Neil to chime = in on the difference between his and Tracy's PSRU, but the prop shaft = bearings ride on Tapered Roller Bearings. The oil inlet is on the = front half with 1/4npt return on the side. There is also a 3/8npt return = on the bottom of the rear section.

My whole = post was basically saying, gravity return isn't enough. The psru still = gets pressurized even with the smallest of restriction. Putting a vent = line on top, turns into another pressured outlet for the oil to return. = Still, a vent line on top I'd recommend to help the returns.

I have a temperature prob in the PSRU. I = could be wrong, but having the psru gears pressurized would cause more = heat? I'll see what the datas shows.

- Matt = Boiteau


On Sat, May 22, 2021 at 12:10 AM David Leonard wdleonard@gmail.com = <flyrotary@lancaironline.net> wrote:
Ok, Here = is my third comment.  Yes you should absolutely vent your = crankcase.  In addition to the stock vent located on the oil filler = neck, I also eventually installed an additional 1/2 in. vent.  Both = of these lines go through an oil/air separator which is vented in = the low pressure slipstream and drained out the gear leg.  And = still it is not perfect, but improved since the early hours.

As an aside,  I can = tell you that increased blow-by is usually the first indication that I = am due for an engine rebuild (among several other more = imminent indications like a sudden loss of power).  I = recommend keeping track of blow-by (how much oil is caught by the oil = air separator).  If you start getting a lot of oil in the can, you = will need a rebuild soon.

Dave Leonard
Turbo Rotary RV-6


On Fri, May 21, 2021 at 6:19 AM Matt Boiteau mattboiteau@gmail.com <flyrotary@lancaironline.net> wrote:
I played = around the past few days with oil and psru. I added a psi gauge on top = of psru,and vented the housing back to the oil dipstick tube. I have an = oil breather tube from the fill port. We should have a vent on the oil = crankcase. Without it, I did a pull and turned off the engine and 5psi = stayed within the system until I cracked open the dipstick to relieve = the pressure.

On Neil's PSRU, the oil inlet is on the front half. The front = drain is on the side, which connects to the back drain that is an10, = then to the oil pan.

Anyways, the stock = psru inlet restrictor was 9/64. Once warmed up and running at 2200rpm = static on the ground, engine oil is about 100psi for me. PSRU pressure = was about 2.5psi and lots of oil was venting back into the oil dipstick = tube. I kept on sizing down the restrictor until 1/16th. That = mostly kept the vent clean and clear of any pressure build up inside the = psru.

I'm not sure why Tracy = recommends having the psru fuel of oil, maybe uses different = bearings then Neil's? =46rom a truck gear case perspective, plantey = gears only need a coating of oil, not full and pressurized. I'm probably = wrong, but throwing it out there. ?.?

- Matt Boiteau
--
Homepage:  http://www.flyrotary.com/
Archive and UnSub:   http://mail.lancaironline.net:81/lists/flyrotary/List.html<= br class=3D"">

= --Apple-Mail=_7C3ACF43-48BE-4AA0-9183-81049B5530C2--