Repositioning inlet/outlet fittings

Way this condenser came, fittings pointed straight out the side. Changed them to 90 degree elbows thinking that might work. Test fit proved it didn’t---alignment between male and female were not quite right. This is due to the condenser being tilted forward at the top and angled in at the rear. Nothing is perpendicular. Might have been possible to accept the misalignment---as in force it to work. Thinking vibration and stress in the fitting areas might turn ugly downstream, that led to sorting this out sensibly now rather than later.

Wondering exactly how this condenser is made, particularly in regard to what bulkheads must be in the side posts to control refrigerant flow, I called the manufacturer and spoke with the engineer dealing with this type unit. Get a person who enjoy's discussing their contraption and even a simple product like this condenser turns mystical. Hat's off to engineers!

http://forums.pelicanparts.com/uploa...1511900361.JPG

http://forums.pelicanparts.com/uploa...1511900361.JPG

Fellow pointed out the slight dimples located on the fin-side of the posts. This indicates where each bulkhead is.


http://forums.pelicanparts.com/uploa...1511900361.JPG

This thing has 3 bulkheads.


http://forums.pelicanparts.com/uploa...1511900361.JPG

The resulting flow.

Am dealing with fittings tomorrow. Today am reorienting myself to where things stand with the electrical. (I go on vacation and some things I filed in my head... not there when I get back. Reorientation is essential. I make lost of drawings---that helps.)

Wiring in car is completed… but not yet tested. Arduino bundle is stuffed under dash behind ash tray. Will post final electrical diagram after testing.


Bucket buildout

http://forums.pelicanparts.com/uploa...1512911474.JPG

Raw bucket. Bondo in bottom corners fills minor deformations that came with bending the metal into form. Deforms don’t matter since this is not a beauty contest and… bucket will be covered with insul. I wanted to check two bondo types to see if one was better so did it here. (Grey and red bodo perform the same as far I can tell.)


http://forums.pelicanparts.com/uploa...1512911474.JPG

http://forums.pelicanparts.com/uploa...1512911474.JPG

Air flow through condenser was tested (with bilge blower) early in project. Found were some areas getting much more air than others (as was expected given the pointing of the inlet.) To improve air spread, deflection to the top corners and towards the front was needed.

http://forums.pelicanparts.com/uploa...1512911474.JPG

http://forums.pelicanparts.com/uploa...1512911474.JPG

Checking inside to make sure deflector parts do not contact condenser’s surface. (Top pic looks at rear area. Bottom looks at front.)


http://forums.pelicanparts.com/uploa...1512911474.JPG

To keep bucket from heat-sponging, it gets insulated. Insulation is foil capped foam with peel & stick base. Am not using peel & stick to allow insul to be easily removed downstream if needed. Is attached at all ends with foil tape.

http://forums.pelicanparts.com/uploa...1512911474.JPG

http://forums.pelicanparts.com/uploa...1512911474.JPG



http://forums.pelicanparts.com/uploa...1512911474.JPG

Ports have now been pointed to the hoses. Angles were created by heating 90 degree elbow tubing and with a box wrench on port nutheads… bending the ports into position. 71 year young machinist does this tig-port work for me. In “modern" business environment where speed-of-creation is pushed & pushed… I watch Luis and there’s absolutely no sonic boom to the speed he works at. Is a fine reminder that quality is one thing. Speed is another.

While pointing ports to hoses is good for hose fitting, moving both ports off their 90 degree angle has caused an interference between the ports & hoses and the guard plate (mounting plate for guard is seen in pic above.) Rather than put brakes on progress to solve this puzzle now, will solve it later. (I know this is risky---postponing solutions can bite back hard downstream!… Butts… Sometimes better ideas come as a result of postponing. Am counting on the latter here.)

http://forums.pelicanparts.com/uploa...1512912231.JPG

Screen was created (early during project) to protect condenser’s exposed fins. A foil mold was taken with the unit in the fender to determine what dimensions were tolerable.

http://forums.pelicanparts.com/uploa...1512912231.JPG

While installing screen... it looks heavy. Not in weight but in form. Am not liking this direction now. Knowing the condenser's area, a horizontal screen between the condenser and exhaust area seems a better solution. As I look at the screen sitting loosely on condenser, the question of whether to now do a fitting for a redesign comes to mind. Answer… not happening---gona move on with what’s in hand.

http://forums.pelicanparts.com/uploa...1512912231.JPG

Trim holds screen in place.

Next…

Hardware is now completed with one exception---a short section of hose is needed for the existing outlet line to reach the condenser. Not sure how to approach this. If anyone knows of a “perfect splicing” technique… please post. Otherwise I’ll go with couplings. Need to add roughly 5” length of hose.

Before installing bucket and duct… will test brushless turbine connected by itself to junction in wheel well. Bypass switch was included primarily for this testing purpose. With bypass OFF, system operates when AC operates---which it does not at this stage. (There’s no refrigerant in system yet.) Will test electrical this week.

Karl before giving up on your little blower motors designs and installing a Spal type fan, you might want to think of running your 4 inch motor solution with a kind of a hand gun silencer or auto muffler air baffle added designs, and set your motor to maximum high speed to see if they can produce enough Air CFM Pressure into your PF condenser shroud to carry away the condensation heat

Kel... no one's throwing in towel on brushless turbine, a.k.a. "little blower." With 70 mph of exhaust air speed, there's enough cool* air to make this work. I've "noise" tested unit in the car and there's no issue with turbine spinning at 80% capacity. Is it worth running it at any higher speed? From what I've seen of the air moving through the condenser... I don't see need for running motor at full throttle.

* "Cool" is based on temp of air ahead of rear wheel compared to air temps behind rear wheel. To respect all rear fender condenser systems with Spals, this project claims NO superiority to the Spal solution. Should be clear to anyone making a comparison that Spal path is actually far superior to this ducted air bucket brainfart on the basis of simplicity. Whether one system is measurably better at condensing... we'll never known---side-by-side test of both systems will most likely never happen. Pardon me for repeating project's mantra for those who know it > Reason for doing this project = exploration. Question of whether or not it's feasible to take air from ahead of the rear wheel and deliver it (with some measure of umph) to a condenser behind... that was partly the initial inspiration for all this. Now close to a final install, is safe to say "ya" to that initial question. Not distinctly asked but surly part of the initial feasibility question is the aspect of durability / maintenance. If not equal to my prior Spal system---that required minimal maintenance---I'll be putting Spal system back. We'll have the answer to that within a year... perhaps even a few months.

I like your "little blower" and your project very much!!! I was worried you might abandon it from something said when we talked. Keep Going!

question is the air bucket the PFC shroud assembly? This word makes no sense to me related to your 911 A/C system

I had not heard one of these low voltage motors run as a high speed blower until I watched the video and heard it, and read the amount of amperage power they are capable of WOW

Karl If you think about the sound hint I gave you I think IT might help you

Kel... "air bucket" is a shroud of sorts. Am calling it a "bucket" due the air being dumped into it.

If you're talking about the "silencer" in order to crank the speed up, it's an interesting idea... but... the system's config'd including the software loaded being written for 80% capacity. To start remodeling now is not appealing. Bear in mind every idea has to be tested and typically refined. That said, I---and surly others---would be interested in seeing what you have in mind. Sketch what you're thinking of and you're welcome to post it. (I can't get beyond a silencer restricting air flow in some manner... like a muffler... so I'm interested in how you see it working.)

Tested system with brushless-turbine (BT) connected to car and it works via the bypass switch. What that switch is intended to do is ONLY power the BT. Instead, the front condenser fan comes ON as well. The compressor clutch and evap blower did not power ON (as it seems they should together with front condenser blower.)

Will be interesting to sort this one out.

As I said in previous posts, wow. I admire your design, fabrication and commitment. Or maybe that should be you need to be committed. ;)

I know spring comes early in the far south of Florida. I am hoping to hear how this system works in the summer heat and humidity of the swamp state.

Good luck with the project we are all watching.

Thanks Glen. :D Genuinely, your entire, unedited commentary is appreciated.

Electrical

Electrical had glitch (forward condenser fan was running along with brushless turbine when bypass switch was turned ON---only brushless is wanted running when bypass is switched ON.) That's been sorted. Electrical system is done.

http://forums.pelicanparts.com/uploa...1514048920.jpg

http://forums.pelicanparts.com/uploa...1514048920.jpg

Arduino - tells ESC what to do.(Is micro-processor... programmed with Arduino "sketch" coding that ESC understands.)
ESC - Steps 12v down to 5v and supplies 5v to Arduino. Takes info from Arduino and signals/powers brushless turbine as needed. (Cannot run brushless motor without out an electronic speed controller of some sort. This ESC is typically used by RC pilots. Is Turnigy product.)
Relay - Rather than take voltage from AC system to power the ESC, Arduino, and brushless motor, seemed better idea (to me) to use AC system for "signaling" a relay (85-86.) 12v is supplied from car's battery through relay (87-30) to power ESC, Arduino and brushless motor.
Bypass switch - bypasses the "relay signal" from the AC system and supplies 12v directly to ESC (which feeds power to the Arduino and brushless motor.)

1, 2, 3. Output signal pulse wires to brushless turbine. (No ground)
4. "Signal" input from car's AC system. Opens and closes 12v power supply from car's battery to ESC, Arduino, and brushless turbine power.
5. 12v power input from car's battery to operate ESC, Arduino, and brushless turbine.
6. 12v power input supplied via bypass switch. (Allows brushless turbine to be tested independently of rest of electrical system.)

Practicality of creating this system... there is none. (Journey is reason for doing ... exploring chit.)

Howdy Karl,

I think your small HIGH AMPERAGE FOR POWER; AND HIGH RPM" STEP MOTOR" AND FAN IDEA HAS GREAT MERIT TO PRODUCE ENOUGH AIR CFM!!

I am greatly interested in your first fan shown! I would like to know it's air pressure and CFM IF PROGRAMED TO MAXIMUM RPM IN YOUR BUCKET DESIGN (SHROUD DESIGN)

ALSO WHAT OTHER fan blade designs are available for it if known?

Shift your thinking and forget about the high pitched whine for a moment

Your bucket design (SHROUD DESIGN) I think needs more air pressure it could create at maximum RPM you have I don't think ever tried because of your worry about FAN NOISE ?

This might help you understand some things related to SOUND/NOISE and how it can be suppressed down to an acceptable level if you increase fan blade up to a higher RPM TO MAXIMUM rpm as only one example.

https://en.wikipedia.org/wiki/Suppressor

(gun silencer)
------------------


also think of another example

i.e. (engine muffler)
Suppressor

<cite class="_Rm">https://en.wikipedia.org/wiki/Muffler

</cite>

I like we both think out side the box sometimes



You are trying to cool a pfc heat exchanger fins with air molecule 's moving through attached muliti-pass micro-channel to heat exchange moving gas high pressure refrigerant inside the micro-channel.

PFC's are more than 30 percent or more efficient than any other prior technology Refrigerant heat exchanger as a FACT!

All fans create NOISE depending on RPM.

You need or are trying to create enough air pressure and air flow CFM with the gas air molecule 's to cool (heat exchange) high pressure A/C refrigerant gas to change phase to liquid

http://forums.pelicanparts.com/uploa...1514196089.jpg

Kel... this is first fan shown. 150 mm diameter EDF unit. Can see these in operation on YouTube. CFM is unknown---users rate EDFs by thrust weight. Reason for NOT going with something like this is the "dirty" environment a standard EDF like this would be subject to in Porsche config at hand. Conclusion was these fine blades not holding up for long.

Idea of incorporating a micro particle filter in system (to protect delicate turbine blades) was tabled. Idea was rejected on the basis of constant filter changing/cleaning being unacceptable maintenance.

To keep idea of a small, high speed fan alive, a more robust turbine config was needed. It was perhaps found in the metal turbine EDF HP uses to cool their servers. I say "perhaps" because this EDF has yet to be real world tested (for durability.) If it lasts 7 years, great! If it lasts 4 months... no good.

http://forums.pelicanparts.com/uploa...1514199194.jpg

http://forums.pelicanparts.com/uploa...1514199194.JPG

A permanent 1/8" particle filter is at the intake.

http://forums.pelicanparts.com/uploa...1514198496.JPG


Blade types

There are a variety of blades offered for RC flight. Plastic, carbon fiber, metal. It's possible to spend a great deal of money on some of these parts. Doesn't make sense to me drop big dollars on a part when this is an experimental build (that has yet to prove itself in the real world.)

Blade speed / Noise

I know you're a "full speed" advocate in order to get as much air through the condenser as possible. Makes perfect sense. But... noise is a part of the engineering challenge in this case. Doesn't make sense to maximize air flow through condenser only to have to listen to a screaming turbine doing it! Some may like that noise---is not my preference. Muffler? That's interesting idea BUT, can it be done without sacrificing air flow?

Currently the on board EDF is set for 80% capacity. I tested EDF speeds, materials, duct lengths, and some other variables... all to balance max-air-flow against an acceptable noise level. 100% (full throttle) was tested and as I recall the noise level decreased as you mentioned it would but there is a high pitch frequency at full throttle that's mentally disturbing. 80% turbine speed creates a barely audible sound as heard from inside the cabin, windows closed, engine at idle. And there's NO annoying high pitch frequency. Assumption = when driving around, system will be inaudible. Running at 80%... also seems a positive in terms of brushless motor conservation (compared to running at 100% capacity. Whether this is realistic or not is unknown.)

Duct insulation seemed a good noise reducing solution. It's not. With two open ends to this system, duct insulation only serves to cushion duct against car, and to minimize system from heat sponging in area behind the rear wheel (near engine's exhaust pipes.)

Insulating the car was also an idea tabled. Some interesting materials were brought to light. Given tests I performed, conclusion = most efficient way to control noise in this scenario is by controlling turbine's speed.

Karl take a look at this little China BrushLess StepFan Hot and Cold 12/14 VOLT BLOWER Motor

We will come back to our propellers discussion; remember I am a marine engineer and marine engineers use propellers on vessels for drives both high and low speed drives for water thrust besides hundreds of other things we do on fully self contained vessels

You may want a different blower and/or controller, kind of like or similar but different to what I am showing you that is made for HVAC blowers control, instead of for flying drones or airplanes for thrust like you are using now.




Look at the controller circuit boards, and notice the additional RPM FINGER control knob on the fan rpm pot; also notice THIS BLOWER as only one possibility. I bet this China company might have exactly what you need among their many brushless kinds and size of Blowers?

Look at these!!!
<dl class="util-clearfix" data-spm-anchor-id="a2700.details.tabs.i1.570d8028VxBXFf"><dd class="item">Performance Data</dd><dd class="item">Drawing</dd><dd class="item">How to Connect</dd><dd class="item">Controller Spec</dd></dl>
https://www.alibaba.com/product-detail/High-pressure-low-noise-hot-and_60124511654.html?spm=a2700.7724838.2017115.209 .7f8c2094KXQaTj


Part Name: High pressure low noise hot and cold air blower ; Part No: WS9250-24-220-8;
Voltage: 24Vdc;
Max Pressure: 60cm H2O;
Current at Max pressure: 2.8 A;
speed at Max Pressure: 27,000rpm;
Max Airflow: 1,000 LPM;
Current at Max airflow: 5.5 A;
Speed at Max Airflow: 22,000rpm;
Hall sensor electric Angle: 120 degree;
Magnet poles pairs: 2 pole pair;
Resistance: 0.6 Ohms;
Inductance: 0.2mH;
Noise level: 75 dBA;
Protection class: IP20;


NOTE: THIS BLOWER MOTOR AND CONTROLLER ALSO RUNS @ 12 VOLT DC and PRODUCES 250 CFM which should be enough for your PFC

Kel... I know your credentials and do appreciate your creative enthusiasm and input. The 12v direct power requirement is wonderful---super simple compared to the demand brushless motors impose. What I found when digging into centrifugals was not a single compact unit that moved major air. (Unless I'm mistaken in my calculations and it's proven I can be... 1,000 LPM is 35 CFM. Second opinion required.) A 4" bilge blower supposedly does around 190 CFM and draws 2.5 - 3 amps. Put a duct on a bilge blower and there's not a whole lot of air left. Bilge blower was first air mover tested for this project...

http://forums.pelicanparts.com/uploa...1514317635.JPG

http://forums.pelicanparts.com/uploa...1514317297.JPG
Unit is OFF in this pic.

Based on my digging (like a rabid dog who's lost his bone) through options to move significant air with a small unit... don't believe brushless turbine can be beat. Problem is electronics required. I went down brushless path to see how that direction would pan out. It's far too complicated to sensibly deal with relative to getting air through a condenser.

Am NOT saying there's NO suitable 12v air mover out there for a ducted solution be it centrifugal or otherwise---am saying I didn't find it.

If you know of a compact 12v blower that can push 70 mph of air (as measured by an in-air-stream anemometer)... post it please---that would be a major find.

http://forums.pelicanparts.com/uploa...1514317954.JPG
2.75" O.D. housing brushless turbine currently in system. This is second test with anemometer held in vice.


HAPPY HOLIDAYS and BEST FOR 2018 TO ALL MY PORSCHE BROTERS & SISTAS!

.

Still editing this

Karl

I VERY MUCH LIKE YOUR PROJECT!!!! I THINK this motor has good potential to produce enough CFM for good PFC Cooling heat exchange

"STAY WITH YOUR DC BUSHLESS STEP MOTOR IDEA" it might just work GREAT with a different FAN PROPELLAR;

but IS EASIER TO use a different BRUSHLESS Controller YOU DO NOT NEED TO PROGRAM like I showed you, THAT HAS AN ADJUSTABLE POT for finger tip FAN control AND IS Made For HVAC/ fan speed control

Forget the regular DC tube bilge blower; they do not have enough CFM; unless you you go to a much larger air inlet centrifugal SIZE like this spal centrifugal blower BELOW

BTW: forget your digital air speed meter it only measures air speed ve·loc·i·ty !

For CFM measurement calculation You would need a MANOMETER for 2 differential air pressures, or a to measure static and ,

To calculate Air Flow in Cubic Feet per Minute (CFM), determine the Flow Velocity in feet per minute, then multiply this figure by the Duct Cross Sectional Area.


http://forums.pelicanparts.com/uploa...1514340744.jpg

The SPAL Output for this blower nozle square connector is I think 4 X 4 inches.

This blower puts out more then enough CFM for a PFC A/C HEAT EXCHANGER, THE intake is about 8 inches

Hi Reid. I really like those centrifugal blowers. The standard bilge blowers are noisy and not very durable. Some of the centrifugals draw a lot of current. Not sure where the optimum between noise, flow and current lies.
Dave

YOU USE / You need a pitot tube that's made for sensing velocity pressure. Nothing really special or rocket science about em. Essentially two tubes.



manometer
http://rover.ebay.com/ar/1/711-53200...r%26_sacat%3D0https://www.ebay.com/sch/i.html?_from=R40&_trksid=p2380057.m570.l1313.TR0.T RC0.H0.Xmanometer.TRS0&_nkw=manometer&_sacat=0


====

To calculate Air Flow in Cubic Feet per Minute (CFM), determine the Flow Velocity in feet per minute, then multiply this figure by the Duct Cross Sectional Area.

Air Flow in CFM (Q) = Flow Velocity in Feet Per Minute (V) x Duct Cross Sectional Area (A)

https://www.bapihvac.com/application-note/determining-duct-air-flow-in-cfm-using-the-bapi-pressure-sensor/

=============



static pressure to cfm?

static pressure to cfm? - Page 2

Howdy Dave!
all blowers and fans & propellers make noise from fairly quiet to very noisy

the propellers of different types of the blades cavitate air molecules at different frequencies of the sound spectrum and loudness

It depends on variance of RPM OR PITCH ANGLE OF BLADE and type

it takes power to make thrust, the more thrust the more power, its all proportional to each other and CFM

CFM Measurement

manometers

https://www.dwyer-inst.com/Products/AirVelocityIntroduction.cfm

https://www.ebay.com/sch/i.html?_from=R40&_trksid=p2380057.m570.l1313.TR1.T RC0.A0.H0.TRS0&_nkw=manometers&_sacat=0

Condenser's front guard


Guard was to be a flat plastic plate mounted ahead of condenser on a bracket. Plan changed due to angling condenser's ports (to better face hoses)... this created an interference with the planned guard. Decided to keep moving ahead and solve this puzzle later. Now is later.

http://forums.pelicanparts.com/uploa...1514895132.JPG

Insulation on bucket's leading edge... would surly get torn up due to debris abrasion.


http://forums.pelicanparts.com/uploa...1514895132.JPG

http://forums.pelicanparts.com/uploa...1514895132.JPG

0.02" aluminum sheet.

Putting bend in to wrap guard's leading edge around front of condenser.

http://forums.pelicanparts.com/uploa...1514895132.JPG

http://forums.pelicanparts.com/uploa...1514896490.JPG

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http://forums.pelicanparts.com/uploa...1514895132.JPG

http://forums.pelicanparts.com/uploa...1514895132.JPG

Backing plate is behind guard to keep rivets from cratering sheet metal.


http://forums.pelicanparts.com/uploa...1514895132.JPG

Condenser's ready to install.


.