X-CGP-ClamAV-Result: CLEAN X-VirusScanner: Niversoft's CGPClamav Helper v1.23.0 (ClamAV engine v0.103.0) From: "Charlie England ceengland7@gmail.com" Received: from mail-ot1-f49.google.com ([209.85.210.49] verified) by logan.com (CommuniGate Pro SMTP 6.2.14) with ESMTPS id 1166118 for flyrotary@lancaironline.net; Wed, 27 Jan 2021 21:02:17 -0500 Received-SPF: pass receiver=logan.com; client-ip=209.85.210.49; envelope-from=ceengland7@gmail.com Received: by mail-ot1-f49.google.com with SMTP id i20so3765852otl.7 for ; Wed, 27 Jan 2021 18:02:19 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=subject:to:references:from:message-id:date:user-agent:mime-version :in-reply-to:content-language; bh=yYEXQk5VxQb3+sBGrQnyU+PjOIr/oNF9sLl2Zov9k5U=; b=eVZg8GzrAh4/E97nRZDKjkIquErQqmnBXPXAdD5u+xplzI2ea1+N8RSIdpYAG3MfG3 +srqtWBbVhNh5NoJ8AJXhj+vfoPJKd+MfQAJ8AXFzQPOySBs1WRjOA3DpAR0QWgS1LtY /p3GGjwuCCMV5a9BC+SnS+c1pMQ1VF+K2Nu3lKSzJx3bo/ZKWRydNryQ4KZMUTzPmNQt H8ccLRKOX3rm8lc8G/lVmoNCnUO0CUTkJTCMgfiGhPmR+pVTJRnZMGMBJMrIQA4pN1q7 TzB/FAKKxWpok2HkPUzc8wDiXaT6vOKSginFukePUUHvUT+5dIaM0f7f/d8FVBoXKvZQ QOcw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-language; bh=yYEXQk5VxQb3+sBGrQnyU+PjOIr/oNF9sLl2Zov9k5U=; b=CwIcseRaEe0YsmoVE8v84r7tUNkWVcCALlnjD0sKtqyeFyGXogP605wnrB1G8pspyn u7zH5x0YrFiwmi4CAKeG1ZtX8fDKSz4B/yVC2P44Ac/9hSNxCZALFA1RB4lNAbSF8Zqc D6VZ2lLwHXRE5e7nnxE/odV+K3DBm8hos7+IWujE9izMlLsT+ly0ViUP6OCR7M3aFUG2 eF5hKN+4FbxXwmCE0xbSUEQbQAa9/Q5KBuSVjfTr/4rNVeUX5qZiUSspkeS9EeCPsybj wL5WnBt84d0pZzpPqZXMp1h52IimBBcz7T6Y+fNZV9lA64ucGJO+Az6+rP7kGr4s3ULX NOEA== X-Gm-Message-State: AOAM531dBi/FO9oAeEITBtBNMU672y0d8anzN1cwWaFyQ/Edl2MLHSGP j2dtHfTpqX+X9WV1kvcV+T8EVkKIvqM= X-Google-Smtp-Source: ABdhPJwKqqbVH5Yxr1/Z0eTWJkQHGf9cs0EHsusq5tHHpLpI6TTdSHBteazgDDxS3GsRP41hYcbndA== X-Received: by 2002:a9d:4c83:: with SMTP id m3mr10048066otf.353.1611799320989; Wed, 27 Jan 2021 18:02:00 -0800 (PST) Return-Path: Received: from ?IPv6:::1? ([2607:fb90:d05b:67bd:85b1:e757:fc8b:7003]) by smtp.googlemail.com with ESMTPSA id n30sm742124otj.42.2021.01.27.18.01.58 for (version=TLS1_2 cipher=ECDHE-ECDSA-AES128-GCM-SHA256 bits=128/128); Wed, 27 Jan 2021 18:02:00 -0800 (PST) Subject: Re: [FlyRotary] Ross Farnham - Cooling video To: Rotary motors in aircraft References: Message-ID: <567c1ef8-7ffd-6701-3877-36084bff04f4@gmail.com> Date: Wed, 27 Jan 2021 20:04:18 -0600 User-Agent: Mozilla/5.0 (Windows NT 6.1; Win64; x64; rv:78.0) Gecko/20100101 Thunderbird/78.6.1 MIME-Version: 1.0 In-Reply-To: Content-Type: multipart/alternative; boundary="------------1D105B851289E50BBDD7D6D5" Content-Language: en-US X-Antivirus: Avast (VPS 210127-12, 01/27/2021), Outbound message X-Antivirus-Status: Clean This is a multi-part message in MIME format. --------------1D105B851289E50BBDD7D6D5 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit On 1/27/2021 7:06 PM, Matt Boiteau mattboiteau@gmail.com wrote: > Ross does the SDS EFI system and did 2 videos on cooling his Subaru > engine. > > https://www.youtube.com/watch?v=GGXXEgqhmmc&ab_channel=rv6ejguy > > > It seems him and Tracy agree that we need a thicker core, then the 1" > Paul L kept on suggesting. My coolant rad is almost as wide as the > plane with the 1" truck core. > > I'm definitely not happy with my cooling setup, but needed to get > moving and finish the plane. Can sit around all day talking about it, > or start with something and get better in time. I'm done the > flyoff hours in FL and hoping to bring the plane back to Canada in the > spring where I can tinker with it then. 3D draw things out and get > suggestions from people then. > > What do you guys think of a belly mount coolant rad? How would we plum > the exhaust out of the way? Keep oil coolant in the cowl? Or Below the > engine? > > - Matt Boiteau I think that a good starting point for engineering issues is to look at what's already been demonstrated as successful. 1" thick rads (or even thinner) work great in cars, where there's plenty of room and they spend most of their time barely moving (minimum air pressure delta across the core). On the other hand, a typical a/c oil cooler is 3"-4" thick. And if what I read is correct, most NASCAR and other racers run radiators that are in the  same thickness range. Racers and a/c both operate in the same speed range, with roughly the same delta-p available (assuming proper diffusers). My takeaway is that something like a Pietenpol or Cub-type a/c would benefit from a large area, thin rad, while faster planes can use thicker cores, which have the benefit of letting the airframe be more aerodynamically efficient. The compromise is poorer cooling performance while idling or taxiing. Location is what you can make work. Ross' system is orders of magnitude better than his original system. But have you looked at his original system??... There are things that still could be improved by quite a bit on his system, like not letting the cowl exit air feed into the rad cooling inlet. Also note that he still needed turning vanes in his diffuser. I'm not knocking turning vanes; I'm using them in both my diffusers. But I've got everything inside the cowl (very short, curved diffusers), without the advantage of a really long, straight diffuser.  Another thing to remember is that he's flying a relatively heavy engine, compared to the stock Lyc in that airframe. Moving his cooling aft likely helped his CG. IIRC, when Tracy did his 1st rotary install in the -4, he considered a ventral rad system but because the 13B was *lighter* than a Lyc, he needed to keep the weight forward. My experience matches Tracy's; my FWF weight (less fluids) is ~332 lbs, which is lighter than a Lyc FWF. FWIW, Charlie -- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus --------------1D105B851289E50BBDD7D6D5 Content-Type: text/html; charset=utf-8 Content-Transfer-Encoding: 8bit
On 1/27/2021 7:06 PM, Matt Boiteau mattboiteau@gmail.com wrote:
Ross does the SDS EFI system and did 2 videos on cooling his Subaru engine.

https://www.youtube.com/watch?v=GGXXEgqhmmc&ab_channel=rv6ejguy

It seems him and Tracy agree that we need a thicker core, then the 1" Paul L kept on suggesting. My coolant rad is almost as wide as the plane with the 1" truck core.  

I'm definitely not happy with my cooling setup, but needed to get moving and finish the plane. Can sit around all day talking about it, or start with something and get better in time. I'm done the flyoff hours in FL and hoping to bring the plane back to Canada in the spring where I can tinker with it then. 3D draw things out and get suggestions from people then.

What do you guys think of a belly mount coolant rad? How would we plum the exhaust out of the way? Keep oil coolant in the cowl? Or Below the engine?

- Matt Boiteau
I think that a good starting point for engineering issues is to look at what's already been demonstrated as successful. 1" thick rads (or even thinner) work great in cars, where there's plenty of room and they spend most of their time barely moving (minimum air pressure delta across the core). On the other hand, a typical a/c oil cooler is 3"-4" thick. And if what I read is correct, most NASCAR and other racers run radiators that are in the  same thickness range. Racers and a/c both operate in the same speed range, with roughly the same delta-p available (assuming proper diffusers).

My takeaway is that something like a Pietenpol or Cub-type a/c would benefit from a large area, thin rad, while faster planes can use thicker cores, which have the benefit of letting the airframe be more aerodynamically efficient. The compromise is poorer cooling performance while idling or taxiing.

Location is what you can make work. Ross' system is orders of magnitude better than his original system. But have you looked at his original system??... There are things that still could be improved by quite a bit on his system, like not letting the cowl exit air feed into the rad cooling inlet. Also note that he still needed turning vanes in his diffuser. I'm not knocking turning vanes; I'm using them in both my diffusers. But I've got everything inside the cowl (very short, curved diffusers), without the advantage of a really long, straight diffuser.  Another thing to remember is that he's flying a relatively heavy engine, compared to the stock Lyc in that airframe. Moving his cooling aft likely helped his CG. IIRC, when Tracy did his 1st rotary install in the -4, he considered a ventral rad system but because the 13B was *lighter* than a Lyc, he needed to keep the weight forward. My experience matches Tracy's; my FWF weight (less fluids) is ~332 lbs, which is lighter than a Lyc FWF.

FWIW,

Charlie

Virus-free. www.avast.com
--------------1D105B851289E50BBDD7D6D5--