Author Topic: Ashwamegh cooling ..part 2  (Read 152 times)

32 coupe

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Ashwamegh cooling ..part 2
« on: September 12, 2021, 01:18:11 AM »

So back on this for a moment....

Radiator,  fan , pump and plumbing installed.
The wiring and plumbing are temporarily during testing.

I have not installed thermostat's at this point and am running the pump and fan while running.
On a 90 F day the water discharge from the heads are running about 180 F in shade with about
a 5 F rise in direct sunlight. This is with a 4K load......

I ordered a larger water pump as the "yard sale" pump I don't believe will move enough water when
the t-stats are installed. The pump now moves 1.3 gallons a min. vs the new pump will move 3.2 .
I will probibly machine the water exhaust manifold to hold a stat for each head.

I spent some time setting the rack adjusting the exhaust temps and managed to get them within 8 degrees
or so of each other. I'm happy with that.

Enjoy !



« Last Edit: September 12, 2021, 01:03:14 PM by 32 coupe »
Metro 6/1 turning a ST 7.5 KW gen head
Changfa 1115 turning a ST 15 KW gen head
Ashwamegh 2/25
John Deere 110 TBL
New Holland TC 30

"I was sitting here reading this thinking what an idiot you are until I realized it was one of my earlier posts !"

mikenash

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Re: Ashwamegh cooling ..part 2
« Reply #1 on: September 12, 2021, 07:56:03 PM »

So back on this for a moment....

Radiator,  fan , pump and plumbing installed.
The wiring and plumbing are temporarily during testing.

I have not installed thermostat's at this point and am running the pump and fan while running.
On a 90 F day the water discharge from the heads are running about 180 F in shade with about
a 5 F rise in direct sunlight. This is with a 4K load......

Just a comment - folks who work on water-cooling heat-exchangers and the like will tell you that more is not better.  There's an optimum rate at which water flowing over surfaces can take heat away from them and increasing that flow can reduce the efficiency of the process rather than improve it?  I have seen this several times in heat exchangers which are cooling hydraulic systems.  In those cases it was better to increase the size of the water reservoir dramatically so that water entering the heat exchanger was always cool - rather than to cycle water faster.

Better-educated folks will know the numbers on this, so just a comment.  Cheers`

I ordered a larger water pump as the "yard sale" pump I don't believe will move enough water when
the t-stats are installed. The pump now moves 1.3 gallons a min. vs the new pump will move 3.2 .
I will probibly machine the water exhaust manifold to hold a stat for each head.

I spent some time setting the rack adjusting the exhaust temps and managed to get them within 8 degrees
or so of each other. I'm happy with that.

Enjoy !

mobile_bob

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Re: Ashwamegh cooling ..part 2
« Reply #2 on: September 13, 2021, 01:37:45 AM »
i have never worked with a lister/oid, however i have large engines and of course the s195 changfa

in development of the s195 for the trigenerator, i removed the hopper and installed the plate, and ontop of that an old tstat housing off a little honda car from a pikapart lot.

i put a radiator off a nissan sentra circa '87 or so

then i installed a bosch auxilliary heater pump, off an old audi from the pikapart lot

i used the same theory of operation typical of heavy trucks in that the tstat is used only to get the engine up to temperature as quickly as possible.

the tstat is a 195d F unit
the little pump moves maybe a gallon/minute as it is plumbed into the drain cock port at the bottom of the cylinder casting which is 1/4" pipe threaded.
the radiator is cooled by the oem nissan electric fan, which is controlled by the oem fan temp switch

the system runs under full load between 204 and 214 deg F, so the tstat stays open and does not regulate the engine temperature.

the engine is rated at 12hp continuous, but under a closed system that is controlled like this it will sustain 15hp continuous and burn cleanly with no smoke.

the only failure i had was a blown head gasket that a happened on the test stand when i forgot to turn on the switch that provided power to the fan.  it ran up to 260F under full load and was running when i shut it down, didn't find out it had a blown head gasket until i let it cool down and tried to restart it.

new gasket, from an s1100 (an upgrade higher quality gasket that will fit) and back in business again.

i see no reason why this same theory of operation could not be applied to a lister/oid
it is my belief the controlling factor as to continuous hp rating is that it is limited to the type of cooling used,  use a hopper or convection cooling and you have to derate, use a closed and controlled system and you can get more power output.

yes hopper or convection systems are simpler, however the argument that closed systems with pumps, fan's, radiators are prone to failure, is in my opinion not a well based assertion.  modern pumps, fans, radiators and controls have proven to be very reliable and not prone to failures.

that is "if" one spends a little time to do things right.

i really believe that running these engine hotter makes a significant difference in the engines ability to burn more cleanly and by extension be more efficient.

so i like seeing folks working to include tstats, pumps, radiators and such to their lister/oids, i think there is much more that these engine are capable of delivering.
otherpower.com, microcogen.info, practicalmachinist.com
(useful forums), utterpower.com for all sorts of diy info

Fred8

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Re: Ashwamegh cooling ..part 2
« Reply #3 on: September 15, 2021, 12:22:46 PM »

Just a comment - folks who work on water-cooling heat-exchangers and the like will tell you that more is not better.  There's an optimum rate at which water flowing over surfaces can take heat away from them and increasing that flow can reduce the efficiency of the process rather than improve it? 

That would be applicable in a high power situation where surface area in the engine was limited  with a high thermal load per Sq in of water jacket area.  In engines like this which are large bore, low power, It's pretty much laughable to even worry about it.

What is this, a 2 Lt or so engine doing sub 20 HP?  You could hook the engine up to a fire Hydrant and blast the water though fast as it would go and still not going to make a shred of difference.... only to overcool it.