[1.5.1] Advanced Jet Engine v2.12.1 (Nov 11)

[SpaceToad 58]

Do precoolers help cool compressing free-stream air entering the engine? If they don't, they should, as that would help with SABREs at trans-hypersonic/hypersonic speeds.

[blowfish 2,461]

28 minutes ago, SpaceToad said:

Do precoolers help cool compressing free-stream air entering the engine? If they don't, they should, as that would help with SABREs at trans-hypersonic/hypersonic speeds.

Precoolers don't do anything at the moment.  I've wrestled with this a bit - really, an engine like the SABRE wouldn't even function without a precooler, so it should be included in the engine.

[jab136 5]

5 minutes ago, blowfish said:

Precoolers don't do anything at the moment.  I've wrestled with this a bit - really, an engine like the SABRE wouldn't even function without a precooler, so it should be included in the engine.

I mean, you could always make it a required part... especially for the SABRE, for which the IRL equivalent uses LOX as an oxidizer which you can't get from atmospheric air without a precooler...

Edit... or you could mod the precooler to have the option to generate oxidizer and then also modify the SABRE to only run on oxidizer and fuel...

Edited August 18, 2016 by jab136

[blowfish 2,461]

15 minutes ago, jab136 said:

I mean, you could always make it a required part... especially for the SABRE, for which the IRL equivalent uses LOX as an oxidizer which you can't get from atmospheric air without a precooler...

Edit... or you could mod the precooler to have the option to generate oxidizer and then also modify the SABRE to only run on oxidizer and fuel...

The SABRE does not liquefy the incoming air, so I don't think this quite makes sense.

[jab136 5]

14 minutes ago, blowfish said:

The SABRE does not liquefy the incoming air, so I don't think this quite makes sense.

sorry, my bad, for some reason I remembered incorrectly that the SABRE liquefied the incoming oxygen, however you could still make the precooler a requirement for jet engine phase operation of the in game SABRE...

Edit: would it be possible to define a new resource "chilled air" and make the SABRE require it for non-closed loop operation?

Edited August 18, 2016 by jab136

[damowang2 3]

I have a question: Why does the static thrust of helicopter rotor barely goes over the total weight of craft? It seems that shaft power and static thrust only affects the reaction speed of helicopter, but when the thrust is stable they are always very close to the total weight of craft, resulting in very slow helicopter.

[blowfish 2,461]

3 minutes ago, damowang2 said:

I have a question: Why does the static thrust of helicopter rotor barely goes over the total weight of craft? It seems that shaft power and static thrust only affects the reaction speed of helicopter, but when the thrust is stable they are always very close to the total weight of craft, resulting in very slow helicopter.

Could you clarify?  Nothing about how the rotors perform should depend on the weight of the craft they're on.  If you have a craft that's close to the max takeoff it's going to be sluggish (most aircraft, including helicopters, typically operate at much less than their max takeoff weight).

[damowang2 3]

I am now making a list of screenshots, could you please tell me how to post pictures?

[blowfish 2,461]

Just now, damowang2 said:

I am now making a list of screenshots, could you please tell me how to post pictures?

You would need a third party image hosting site like imgur.  But in my experience, screenshots aren't particularly useful.  Maybe you could try to explain in a little more detail exactly what you're trying to do and what behavior you're getting that you don't expect?

[damowang2 3]

Reproduction step:

 

make a craft out of Huey rotor in KAX, sling a detachable load to make it weighs around 4t,

take it off, observe the thrust in the right-click menu. It should indicate a value around 4kN,

drop the weight. The thrust will gradually drop to the weight of the craft, possibly about 110% so it will barely stay hovering, but any maneuver will cause loss of velocity and height.

 

[blowfish 2,461]

3 hours ago, damowang2 said:

Reproduction step:

 

make a craft out of Huey rotor in KAX, sling a detachable load to make it weighs around 4t,

take it off, observe the thrust in the right-click menu. It should indicate a value around 4kN,

drop the weight. The thrust will gradually drop to the weight of the craft, possibly about 110% so it will barely stay hovering, but any maneuver will cause loss of velocity and height.

 

I tried with a 2t craft and a 5t craft, and the thrust is the same on the runway.  If you take the craft higher in the atmosphere, the thrust will drop off and you will not longer be able to climb when the thrust and weight are about equal.  Is that what you're talking about?

[damowang2 3]

This is a custom engine that I made. Notice the static thrust is 102KN

Now attach two mineral tanks. Notice the reading of Engineer's Report and KER, The empty weight is 5t and loaded weight is 7t.

Now bring the helicopter up. notice that the thrust is 75KN when the mineral tank is attached, so the craft is barely hovering. 

now detach the mineral tank. The thrust gradually dropped to 57KN, still barely enough for the craft to hover.

[kcs123 897]

You are missing point here. On first picture your altitude is ~200m and surface velocity of ~8 m/s. On second picture you are at altitude of ~400m and velocity of 13 m/s.

Max thrust depends on those two properties, not from craft weight. That being said, it seems that those changes are a bit too much, it should not be so much difference in available thrust. Reason for this bug is probably with atmospheric curve not being properly set for KAX engines in the first place. Problem is just enhanced when you have installed AJE on top of that.

[blowfish 2,461]

After doing some experimentation, there does seem to be something a bit off here.  Unfortunately, camlost wrote the original rotor simulation without any documentation, and none of what it does makes much sense to me.  Given that our previous attempts to get in contact with camlost have yielded nothing, I'm not quite sure if anything can be done here.

[Calvin_Maclure 209]

Good day. First off, great mod, love it, thanks to all who are involve. 

Quick question, is there any way to increase to rate at which the turbofan spools up? It does so rather slowly. IRL, turbofans can spool up rather quickly. 

[blowfish 2,461]

18 minutes ago, Calvin_Maclure said:

Good day. First off, great mod, love it, thanks to all who are involve. 

Quick question, is there any way to increase to rate at which the turbofan spools up? It does so rather slowly. IRL, turbofans can spool up rather quickly. 

I do plan to revisit throttle response at some point, but without a lot of hard data about how fast jets actually respond, or a physical model of how fast you can add fuel to the combustion chamber without causing a flameout, it might take a while.  In the mean time, you can set the throttleResponseMultiplier on jets.  If you wanted to say, multiply the throttle rate by 1.25 on every jet, you could use this patch:

Spoiler

@PART:HAS[@MODULE[ModuleEnginesAJEJet]]:FINAL
{
	@MODULE[ModuleEnginesAJEJet]
	{
		%throttleResponseMultiplier = 1.25
	}
}

 

 

[raxo2222 191]

Can we have AJE engines tweakscalable?

And which one allows to fly at highest speed?

Can we have SCRAMJET engine or something, that can operate at higher speeds than 5 machs?

[blowfish 2,461]

19 minutes ago, raxo2222 said:

Can we have AJE engines tweakscalable?

Tweakscale support is messy, and I'm inclined to believe there was a good reason why camlost disabled it originally.  Thrust should scale with r², but mass should scale with r³, so engines would get a worse TWR as you scaled them up.  Is that what you want?

20 minutes ago, raxo2222 said:

And which one allows to fly at highest speed?

Of the pure jets, the J-58 should allow you to hit mach 3.5.  The SABRE/RAPIER should allow you to hit mach 5.5

21 minutes ago, raxo2222 said:

Can we have SCRAMJET engine or something, that can operate at higher speeds than 5 machs?

There's currently almost no data on how scramjets actually perform (tests are classified), nor any equations governing combustion at supersonic speed.  It's kind of problematic without that information...

[raxo2222 191]

14 minutes ago, blowfish said:

Tweakscale support is messy, and I'm inclined to believe there was a good reason why camlost disabled it originally.  Thrust should scale with r², but mass should scale with r³, so engines would get a worse TWR as you scaled them up.  Is that what you want?

Of the pure jets, the J-58 should allow you to hit mach 3.5.  The SABRE/RAPIER should allow you to hit mach 5.5

There's currently almost no data on how scramjets actually perform (tests are classified), nor any equations governing combustion at supersonic speed.  It's kind of problematic without that information...

Well I want to downscale them slightly to have kickstart - there is one engine, that doesn't have static thrust, so it needs others engines to accelerate plane.

Here is plane (Uses RSS/tweakscale/IFS so I can have 1:20 mass ratio pure liquid tanks):

http://www117.zippyshare.com/v/Kb8rcpkz/file.html

--------------------

Since SCRAMJET is so undocumented,  then can we get support from nuclear engines from Interstellar Extended?

Normally these engines can run up to 5 - 6 machs before thrust loss

I think Nuclear Thermal engines on atmospheric mode react differently to incoming air than standard turbojet engines.

These engines run on pure air, heat it up and expel it.

 

[Calvin_Maclure 209]

47 minutes ago, raxo2222 said:

Can we have AJE engines tweakscalable?

And which one allows to fly at highest speed?

Can we have SCRAMJET engine or something, that can operate at higher speeds than 5 machs?

The turbofan (the large 747 type TF) is Tweakscalable. Works both ways, bigger and smaller. Its great, tbh. Allowed me to work several aircraft models because of that. 

[raxo2222 191]

There are 2 jet engines, that have constant ISP:

http://imgur.com/a/narmL

I tested these on launch.

[blowfish 2,461]

7 hours ago, raxo2222 said:

There are 2 jet engines, that have constant ISP:

http://imgur.com/a/narmL

I tested these on launch.

AJE isn't loading properly.  If you show me KSP's log I can tell you why.

[raxo2222 191]

3 hours ago, blowfish said:

AJE isn't loading properly.  If you show me KSP's log I can tell you why.

I'll just reinstall these.

Apparently CKAN doesn't remove 2 solver engine files after uninstall:

They remain here: \Kerbal Space Program\GameData\SolverEngines\Plugins\PluginData\SolverEngines

config.xml and EngineDatabse.cfg

Only 2 engines had constant ISP, others had variable one.

---------------------------------

Reinstall didn't fix it.

I tested only faster one with 4000 ISP now.

Here's log:  http://www52.zippyshare.com/v/NsPajakt/file.html

Its 6 MB - I have a lot of other mods and added and removed mods when I was playing sandbox.

There is some mod incompability

Edit: It was fault of Persistent Thrust mod.

Now engines are working correctly.

 

Edited September 15, 2016 by raxo2222

[Calvin_Maclure 209]

On 9/10/2016 at 11:47 PM, blowfish said:

I do plan to revisit throttle response at some point, but without a lot of hard data about how fast jets actually respond, or a physical model of how fast you can add fuel to the combustion chamber without causing a flameout, it might take a while.  In the mean time, you can set the throttleResponseMultiplier on jets.  If you wanted to say, multiply the throttle rate by 1.25 on every jet, you could use this patch:

  Reveal hidden contents

@PART:HAS[@MODULE[ModuleEnginesAJEJet]]:FINAL
{
	@MODULE[ModuleEnginesAJEJet]
	{
		%throttleResponseMultiplier = 1.25
	}
}

 

 

Sweet! Now, where do I patch this in?

[blowfish 2,461]

2 hours ago, Calvin_Maclure said:

Sweet! Now, where do I patch this in?

Put it in a .cfg file somewhere in GameData