LLK die 10te: Größen und Leistungsstufen | Posts 32+

bafische wrote:

You can probably identify the double-flow liquid cooling loops in the documentation, which largely eliminates the need for T-fittings.

Hi Bavarian,

Unfortunately, the flow pattern is difficult to discern within the complex network of hoses and pipes .

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There are also many publications on this topic (MTZ, especially in the special issue dedicated to 20J TDI engines)

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Hmm, I'll try to get that sorted out... thanks for the tip!

Hello.

The flow pattern is actually quite simple if you have some basic knowledge of the thermal behavior of things like air, etc.

Single-point gas venting is the best option.
1 LLK: influential entry, but double-edged exit.
Connecting pipes are best made of aluminum.
2. LLk, two-stage entry (clear), in a radial engine, single-stage exit.
Here as well, if possible, use aluminum piping.

LLKs should not only be considered based on their intake area, but also factors like exhaust air flow, material of the filter and housings, airflow velocity, etc.


Best regards, Cosi.

Just a quick question: What's the actual difference between the 1Z/AHU and the AFN LLK engines in the VW Golf 3?
The AFN, as far as I know, has a different one.
AFAIK, all G3 TDIs have the same engine oil capacity, regardless of whether they are 90 or 110 horsepower.

The part number differentiates between two models.

3A0 145 805 A was only available in the 1Z.
3A0 145 805 B was available in the 1Z and in the AFN.

Hi.

Log of intake air temperature, with the condition that the ambient temperature is 14°C.

The temperature differences are negligible: approximately 48°C versus approximately 45°C.
Under constant full throttle, the differences should be more pronounced but still not critical.

Best regards, Rainer.

Rainer K. wrote:

The temperature differences are negligible: approximately 48°C compared to approximately 45°C. At constant full throttle, the differences should be larger but still not critical.

I'm just not getting it somehow.
AHF mit 2,2 bar abs. = 0,2 bar über Serie fährt max. LLT at 34,000 feet above AT.

The absolute pressure of the ASZ is 2.4 bar, which is 0.1 bar above the standard value. It can operate at a maximum low-temperature limit of approximately 52K above the ambient temperature.
By the way, it looks similar in the Golf 4 ASZ (from Roger).

As if the ASZ had a smaller load capacity from the factory than the AHF .

@Rainer: By any chance, do you also have air mass readings at around 4000 rpm with the tuning?
My average serum zinc level is approximately 1000 mg per injection.

Hi Ulf,

"At 4000 rpm and 2.2 bar, I have previously always measured 1275mg/stroke, which is the maximum measurable value. It's possible that the mass airflow sensor (MAF) is being overloaded here and measuring too much, or that the engine control unit simply takes the maximum value once a certain output voltage is reached."

Best regards, Rainer.

Rainer K. wrote:

It's possible that the mass airflow sensor is being overloaded here and measuring too much, or that the control unit simply takes the maximum value above a certain output voltage.

Hi Rainer,

That's probably how it is.

With 27% more cylinder filling at 0.2 bar less line pressure, it simply doesn't add up - even if your low-temperature limit is actually 20K below mine (which would result in approximately 6% more air density at the same pressure).


Do I remember correctly that your liquid level and temperature sensor is located in the pipe behind the low-level coolant (LLC) reservoir? Julian's logs also show wonderfully low LLC temperatures, and he has the sensor in the pipe.

My sensor is located in the inlet air duct of the liquid cooling system (LLC), but I haven't been able to fully understand how the measured temperature there should be at least 15 K higher than in the subsequent pipe.

Hello Ulf,

Quote:

Am I correct in remembering that your LD and temperature sensor is located in the pipe behind the LLK?

Yes, but it's only a few centimeters from there to the LLK (likely referring to a specific anatomical landmark).

Best regards, Rainer.

Rainer K. wrote:

Do I remember correctly that your LD and temperature sensor is located in the pipe behind the LLK? Quote: Yes, but it's only a few centimeters from there to the LLK. Hmm, I'm starting to understand something now. Donalexo had written something about the temperature profile in laminar flow. Only the air directly adjacent to the inner surface of the pipe cools down, while the temperature is higher in the center of the airflow. The pipe sensors measure the flow close to the inner wall of the pipe, which is naturally cooled further along each centimeter of pipe length (depending on the temperature outside the pipe). If the NTC sensor were positioned further towards the center of the tube, the logged liquid level temperature (LLT) would likely be higher. However, the airflow within the LLK air chamber is still turbulent (as the flows from the individual LL channels mix together), which means that measurements taken there are likely to be more accurate than those taken in the suction pipes. In other words, the logic values of the intake manifold sensors would be more or less skewed downwards...? Alex, please come

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Hi Ulf,

I don't think that makes a significant difference. My intercooler already has an opening at the top for the boost pressure sensor (now: blind plug for mechanical LDA measurement), so I could, just for fun, swap the mounting locations. However, I haven't checked whether the intercooler I have is the original type that was installed }. It was actually replaced once during a warranty repair.
Best regards, Rainer.

Rainer K. wrote:

My oil cooler already has a hole at the top for the boost pressure sensor (now: blind plug for mechanical LDA measurement), so I could, just for fun, swap the mounting locations.

Wow, that's the perfect research subject!

If you could do that, I would be very interested in the results!

Quote:

I haven't checked whether the LLC (Liquid Level Controller) I have is the original type that was installed.

No problem, it only matters if there are measured differences in liquid levels depending on the measurement point. And even a faulty LLC should still work well enough for that.

Hello Ulf,

In my opinion, Donalexo prioritizes the maximization of 'heat transfer,' i.e., the maximum heat flow (which is energy per unit time), and therefore I can only agree with his statements.

However, for the optimal performance of the air dryer, it's not the maximum heat flow that is crucial, but rather minimizing the inlet temperature (T1) of the compressed air as much as possible, thereby achieving a correspondingly low outlet temperature (T2).

This can be achieved in two ways:

make sure the length of the section to be traversed is sufficiently long.

or

to keep the flow rate as low as possible.

In both cases, the residence time in the heat exchanger is extended, and the temperature difference between T1 and T2 is maximized.

TAW wrote:

to keep the flow rate as low as possible. In both cases, the residence time in the LLk is extended, and the temperature difference between T1 and T2 is maximized.

According to this, a parallel connection of two liquid-liquid heat exchangers would also be effective: The volumetric flow rate is divided, the cross-sectional area of the cooling circuit is doubled (in the case of two identical LLKs), which halves the flow velocity and doubles the residence time again.

This also roughly aligns with my logs regarding flow speed.
At full load in 6th gear at 2000 rpm, the low-temperature coolant (LTC) temperature at the LTC outlet is slightly more than half of what it is at 4000 rpm.

If the mass flow rate is also taken into account as a correction factor (2000 rpm: approximately 1100 mg per cycle, 4000 rpm: approximately 1000 mg), the results fit even better.

Unfortunately, it seems like I won't be able to use two parallel LLMs (Large Language Models) in my setup.
The narrower water cooler from the 100 horsepower gasoline engine cools insufficiently (approximately 2/3 of the cooling system volume, but only about 50% of the cooling capacity of the standard cooler) .

Hello Ulf.

I'm not sure how much the Fabia's front end differs from the Polo's, but take a look:
http://www.forgemotorsport.co.uk/content.asp?inc=product&cat=0013&product=FMINTFAB
(But don't look at the price ).

Best regards!

R.M. wrote:

I don't know to what extent the Fabia front differs from the Polo, but take a look . . .

Thank you, but unfortunately, the front designs are so different that something like that won't fit on the Polo .

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In both cases, the residence time in the LLk is extended

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You must break free from the idea that this convective heat transfer has anything to do with time! You are looking at (quasi-)stationary processes here, not equilibrium processes: I put an ice cube in a glass and wait for it to dissolve, or I fill air into the cooling system and wait for it to cool down...
If you want to calculate the performance of your liquid cooling system, I recommend using the VDI Heat Atlas. However, this requires some technical data about the individual components used in the system.
If you can't obtain those values directly, you can initially assume some default values and then investigate whether a series or parallel configuration is more advantageous under the specific conditions of our TDIs.
Stay cheerful.
Okay, please provide the German text you would like me to translate into English. I will only provide the translation.