Tron999

How does mesh restrict the efficiency of the a/c condensor when you're sitting in LA traffic at 105 degrees? Can you please explain that? How is ANY situation of a/c use going to be higher stress/temperature than that(except for Texas traffic at 120 degrees)?

If the car is moving, you're going to have a helluva lot more airflow - mesh or no mesh - , and the compressor isn't going to be working any harder.

OCBen

Are you a degreed mechanical engineer?

Tron999

No, are you?

OCBen

Yes. .... Among other things.

Tron999

Then please explain how sitting in traffic with or without mesh makes a difference.

OCBen

You won't understand unless you understand thermodynamics and convective heat transfer. That's why I asked if you were an engineer. Didn't want to waste my time trying to explain something that you wouldn't understand.

But to give you a quick simple answer to your question above, it is obvious that if there is no air flow to restrict, the screens will not be doing any restriction. But it is impractical, not to mention ridiculous, to design a screen that pops up out of the way when you sit in traffic with no air flow to restrict.

However, in the case of a radiator, which usually has a fan working to draw in air, the screens will restrict the air flow even while the car is standing still, sitting in traffic, even though the flow is much less than when the car is moving.

Tron999

Just because I'm not an engineer, doesn't mean I'm a moron. I understand that the mesh will restrict airflow, but I don't think the difference is a big deal.

As long as we're not talking about a mesh that is so fine, barely ANYTHING gets through, there's not going to be a problem. Especially not one to cause the compressor to run constantly and cause damage.

OCBen

I didn't call you a moron, but now that you mention it.

You obviously don't understand the difference between laminar flow and turbulent flow, and the effects on convective heat transfer that those types of air flows have, and how a simple screen is able to make a significant impact on the heat transfer rate. It's the same reason why you don't see screens in front of jet engines, where you would think stopping a bird from being ingested into an engine and potentially bringing down an aircraft because of it would be of paramount importance. Ever wonder about that too?

Again, you're making it blatantly obvious you're not an engineer.

Feel free to make whatever mods you want on your own car. No one is stopping you. I for one do not pretend to know more than the Porsche engineers when it comes to the design of the heat exchangers on Porsche vehicles, and I will not make any modifications to my vehicle that is not approved by Porsche.

DerivativesGuy

OC,

I am impressed with your knowledge here. Do you work in the automotive our aerospace industry. I agree its hard to explain these concepts to people. I get that all the time.

nkhalidi

Ben, you bring up good points, but your posts are undermined by your sweeping condescension and belittling tone.

Keep your pristine, virgin, as-God-and-Ferdinand-intended Porsche for yourself, and the rest of us will continue tweaking, modifying, and undermining Porsche engineers' best efforts.

OCBen

Hi DG,

I'm in the Space Intelligence business, a subdivision of aerospace, and I happen to work in the business side of things lately. Yes, it is often difficult to explain some things to those who don't understand, and it gets frustrating for them and for me, but that's how it is, unfortunately.

OCBen

How would you have worded it instead?

DerivativesGuy

I don't think OC was being condescending. Sounds like he was just a little frustrated because he knew more about the topic than others posting here. I am not an engineer but OC really does sound like he knows what he is talking about. I am new to the board here but I have gone back and read many of the posts by OC and others. OC is clearly a (if not "the") leader of this board.

gravedgr

I'm sure you would find (at least) an overwhelming minority who would disagree. Leadership is not determined by the number of posts you make, or the number of people you verbally beat down. Ben (sometimes) has great information, but has a long way to go on delivery.

DerivativesGuy

OC was very welcoming when i joined this board and from what i can tell he is providing mass quantities of useful information to his fellow members. Sometimes leaders need to be stern and often they come across as "know it alls" but often times it is because they do know more than most of us.