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Deep Space Hardware (MARS)

Posted by: rpspeck - Tue Mar 22, 2005 4:57 am
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Deep Space Hardware (MARS) 
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Post Gas Diffusion   Posted on: Tue Apr 12, 2005 10:39 pm
On Gas Diffusion: In physics, one fundamental approach to free diffusion (that “motivated” by concentration gradients, but not by something like a superimposed electrical field) is the random walk concept. In this very effective model, a molecule doesn’t know anything about other molecules at a distance. The molecule in question continues in free flight until it bumps into another gas molecule (after traveling an average distance equal to the “mean free path”). At that point it is deflected into another path (even including reversal). This “Random Walk” process, AS A STATISTICAL AVERAGE, accurately models these diffusion processes. In a fixed time period, the statistical average (one dimensional, planar diffusion) distance molecules diffuse equals the mean free path times the square root of the number of collisions (a common factor in statistics), with a small, fixed numerical adjustment related to how the above factors are defined. The mean free path is proportional to 1/pressure, the collision frequency proportional to pressure itself (but reduced to SQR(pressure) in the computation).

This concept is a cornerstone of modern “Statistical Mechanics and Thermodynamics”. You can try Googling this, but much of this stuff is mathematically dense.

Please feel free to check me, and let me know the result; it has been a long time since I took this graduate Physics class. It would probably be best to call a college professor teaching the class, and ask him.


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Post    Posted on: Wed Apr 13, 2005 8:03 am
Lost me after the word Gas. :)

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Post Re: Gas Diffusion   Posted on: Wed Apr 13, 2005 1:04 pm
rpspeck wrote:
On Gas Diffusion: In physics, ...
I think the diffusion DR_Keith_H is talking about is the lung's ability to take in oxygen, which is clearly less at low pressure.


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Post    Posted on: Thu Apr 14, 2005 1:03 am
Pardon me. I am like Pavlov’s Dogs. You ring the bell, and I regurgitate stuff from old classes and don’t know when to stop. Dr. Keith H. (and I would be pleased to know your last name) rang this bell by mentioning “drying out” of lung tissue. I immediately remembered that at very low pressure (vacuum) vapor streams from a water backed membrane at a tremendous rate. (It leaves a liquid surface explosively, so the membrane is all that is left). It does this largely because the large mean free path removes any obstruction for the escaping water molecules. This is of course irrelevant, since we are not dealing with that kind of vacuum. But the transition from vacuum to pressure is not instantaneous, and the mean free path is still the key factor. I thought I remembered the described, square root effect, continuing up through normal pressures. This could increase drying in some parts of the lung. Alveolar air has always been assumed to be fully water saturated, but that water has to come from somewhere. The portion of the lung stressed by hydrating dry air could change at low pressure. This triggered a recollection that high altitude climbers often mention a persistent cough. I don’t think this is the answer, but I mentioned that possibility.

While I am regurgitating, let me mention with regard to anecdotal reports, that imperfect attempts to prevent anoxia by breathing Oxygen could allow HAPE (High Altitude Pulmonary Edema) to develop. This causes, as implied by the name, Pulmonary Edema complete with conspicuous chest rales. Since this resembles the reported effects, is it possible that the result of too little Oxygen was mistaken for a detrimental effect of the Oxygen itself?


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Post Development Strategy   Posted on: Thu Apr 14, 2005 8:40 pm
Let explain something about what is going on in this forum. I was shocked to realize (while working on homework for an Orbital Mechanics class) that LANDING ON MARS is easier than putting a communications satellite into GEO (Geosynchronous Earth Orbit) from the standpoint of launch capability (Delta V from LEO). That assumes aerobraking, but this was used with Apollo, and with recent Mars missions. (I will supply details if anyone wants them).

Actually, since campbelp2002 has demonstrated his ability with orbital mechanics, I ask him to check my figures. For a single burn at 6400 km Earth radius, I ended up with just under 400 meters per second delta V - ADDED TO THAT REQUIRED TO REACH ESCAPE VELOCITY - to retain enough energy ("V infinity") for a minimum energy transfer to mean Mars orbit. CAN YOU CONFIRM THIS? GTO (transfer to GEO) takes 760 m/s less than escape, but orbital insertion adds 1496 m/s, totaling 736 m/s above escape - AND 336 ABOVE MARS TRANSFER! So LAUNCH to Mars, is not a big problem.

I felt that NASA had LIED TO ME, and everyone else, about how difficult a flight to Mars is. This stimulated me to try a clean sheet analysis of the smallest orbital payload which might make it possible for a human to walk on Mars. It did not, of course, stimulate me to take anything else NASA has said at face value.

Some of you have already laughed at the results of this effort. In point of fact, I have not yet found a serious flaw in the estimates, but flaws will certainly be revealed. Even a round trip, to Mars and back, takes little more total launch capability than used for Moon landings. That leaves two related questions: first, what will it really take, at minimum, to keep an astronaut alive for the trip, and second, how can credibility be developed which will make funding of this affordable adventure possible? I am certain that this effort can, and will, be completed at less cost than a major sporting event!

The answer to the second question was to develop communication with a group of knowledgeable volunteers, who would take this discussion seriously, and would also reflect widespread concerns which must be addressed. Credibility requires that the PRIMARY objections of many individuals be satisfactorily answered. It won't help me to demonstrate a subsystem YOU don't care about (or haven't gotten around to worrying about).

The answer to the first question was to develop communication with a group of knowledgeable volunteers, who would bring their background, their experience, their knowledge and insights to bear on these problems.

YOU MAY NOT UNDERSTAND HOW IMPORTANT YOU ARE TO THIS PROCESS!
This is a brainstorming group. It might seem, at times, that I claim to "know everything", but in fact your comments cause me to both associate and regurgitate stuff I picked up in graduate classes. (Fortunately, you can scroll ahead rather than falling asleep). Your efforts online and elsewhere multiply the knowledge we are able to bring into this process. Your warnings about the nature of internet research ("You can always find the answer you want") are true, and this has always been true of incautious research. If you are not prepared to bolt and wire stuff together to prove it will work, I am.

It is easy to imagine that the world consists of "experts" and ordinary people. But if you have the opportunity to be associated with a well respected research team - as I was - you will find that it includes "ordinary" people who can bring their knowledge and experience to bear on interesting problems. A few team members may have decades of unusual experience, but they don't do all the work, and they don't have all the good ideas! Groups with too many narrowly focused "experts" have made some of the biggest blunders: "by ignoring the obvious". The presence of clear thinking people with broader backgrounds is essential as a sanity check. And beyond that, preparing answers to their questions is an essential preparation before making any results public.

I will ask Dr. Keith H. to comment specifically on this description of an effective research team as I believe that he has more recent experience with research teams than I do.

(Also to Dr. Keith H., relative to "degrees of separation", people often do not answer my e-mails or return my phone calls, particularly if they are busy strangers. The old "6" number is now reduced to some value still greater than 1.)

We are, perhaps, pioneers in the new field of NET Enabled Research (in this very narrow application). Whether we will be recognized as pioneers in space exploration remains to be seen. I am not naive enough to believe that anything accomplished in this area will resemble the days of instant internet billionaires. Rather, I believe this "industry" will resemble the pioneering days of aviation, with pilots struggling to find the money to keep their fragile craft flying - and loving the life!

What I am sure of, is that this team effort can succeed in proving that a lightweight mission to Mars is feasible. This evaluation reflects my long history of successful product developments, and flops. With your continued help, we will prove that an affordable expedition can be done - which will leave only the question - Why not do it?


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Post    Posted on: Thu Apr 14, 2005 9:33 pm
I just completed the following dialog with John Jurist, "A biophysist with a long-standing interest in human factors. He currently resides in Billings, Montana. ..."

Thank you for your feedback. I will follow up on these references. I take this as good news with respect to a lightweight Mars mission, using 100% Oxygen at 4 psi. The simpler systems will be lighter and more reliable. With your permission, I will copy your note to my forum thread on this subject. Richard P. Speck Micro-Space, Inc.

>From: JMJSpace@aol.com
>To: rpspeck@hotmail.com
>Subject: Re: Oxygen Breathing for Mars Missions
>Date: Wed, 13 Apr 2005 19:28:06 EDT
>
>The atelectasis problem is mostly associated with breathing oxygen while
>under acceleration or during pressure breathing (where oxygen is supplied at
>higher than ambient pressure via mask). Military pilots call it "G-cough." It
>appears while breathing more than 70% oxygen after exposure to as little as 3-4.5
>G as monitored by measurement of vital capacity after acceleration exposure
>during flight.
>
>Two references are the conference proceedings for the following conferences:
> "Raising the Operational Ceiling" 13-15 June 1995
> "Hypobaric Decompression Sickness" 16-18 October 1990
>Both were sponsored by the USAF Armstrong Laboratory and held at Brooks Air
>Force Base in Texas. Conference proceedings can be acquired from the Aerospace
>Medical Association. A particularly useful paper for you would be by Ulf
>Balldin -- "Pressure Breathing and Acceleration Atelectasis" presented at the
>1995 conference.
>
>Thank you for your interest in this subject.
>
>JMJ

I give my permission, but keep in mind that a human population living without difficulty at 4 PSI pure oxygen for long periods of time is unproven experimentally.

JMJ


I take this to mean that the Oxygen atmosphere question has never been answered, and that STS and ISS chose mixed gas to avoid this research. Given the long human experience with Oxygen breathing, I personally take this to mean that any effects of pure Oxygen are probably “manageable”: by this I mean that given health maintenance procedures and selection of participants, the personal effects will probably not exceed the effects of “World Class” athletic training. Since the selection, preparation and health maintenance factors are normal in High Altitude Mountaineering (my base line for light weight space expeditions), this clears pure Oxygen as a reasonable design concept. R.P.Speck (And I will still check out the refrences.)


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Post Oxygen Generator Update   Posted on: Mon Apr 25, 2005 8:07 pm
This is a limited update on several ongoing projects. Unfortunately my “Day Job” keeps interfering with these efforts. I will file a preliminary report soon on my water reprocessing system (for Mars Missions), which continues to look promising. I am working on an upgrade to the Micro-Space.com web site, which will simplify continuing updates, including photos and diagrams of the test hardware I am running. Another project I have only alluded to is a lightweight “Man Maneuvering Unit” to make space diving practical, both for orbital “tourists” and for atmospheric reentry. I hope to find an opportunity to demonstrate a small system on a “zero G” flight. Meanwhile, I am preparing manned and unmanned system demonstrations using cable suspension from center of gravity. We have several small rate gyro packages ready for stabilization use (and could resurrect the “Free Gyro” system we used in our successful, gimbaled motor rocket flights).

We are also preparing for more tests of our small H2O2/Methyl Alcohol, liquid fuel rockets. As previously noted, we have built enough of these motors and fuel tanks to begin manned testing. Our concept for working up to full “space flight” (100 km and above) altitudes starts out with tests of the abort systems, which in manned use resembles BASE jumping, with its low altitude parachute deployment. The option is to use a more complicated balloon lift for easier parachute deployment. But in either case, I do not yet have parachute experience, and have no experienced participant interested in these efforts. Thus this work will progress very slowly. The instrumented rockets themselves will fly again next month.

Moving to the breathing problem, CO2 scrubbing is to some extent a “done deal”. Reportedly, Silver Oxide participates in a nice, thermally reversible reaction with CO2 (to form the carbonate). The basic material is available, and the process has been operationally demonstrated. I think the carbonate solution process may integrate better into my overall life support system, but that remains to be seen.

The Oxygen generator has taken several steps backward. There is no question that fuel cells will produce Oxygen in Zero G, and the alkaline system is probably the best choice (and has a reasonable point to inject the water which is consumed). However the commercial vendors express some reservations about CATALYST LIFETIME! With all the fuel cell hype, this is a surprise! It is not at all obvious that catalyst degradation will only occur during periods of heavy use (and not idle or parked times) since the chemical environment is very similar during standby. Personally, I don’t want to buy an expensive Fuel Cell car which will have to be overhauled in less than a year! (And I am still waiting for someone to find a “Hydrogen Mine” to supply the Hydrogen I will need.) Ecologist types should bear in mind that METHANE (aka Natural Gas) SYNTHESIS, CONSUMES CARBON DIOXIDE and water (and quite a bit of energy – like H2 production). When this is burned in an internal combustion engine, the emissions are also a net zero! But those are other issues.

I don’t believe that catalyst degradation is a serious problems for electrolysis. A low reactivity surface just means a higher drive voltage. In a fuel cell, the output power can fall to zero. In the electrolysis unit, the corresponding point still gives 50% efficiency! Since graphite, nickel and many other surfaces will work with no catalytic preparation, this should not be a killer.

As I have come to understand better the mass transfer phenomena in these cells, I can explain the absence of bubbles. The released Oxygen and Hydrogen exist first as dissolved gasses, each at the corresponding electrode. The dissolved gas can diffuse through a thin layer of electrolyte, and the porous (hydrophobic) membrane, into the adjacent gas chamber. Some will also stay in the electrolyte, and some actually diffuse to the opposite electrode, where it will be consumed by “cold” (but exothermic) “combustion”. The later is one of several parasitic processes in a fuel cell, or electrolysis cell. If the dissolved gas “pressure” exceeds the combination of ambient pressure and surface tension pressure, then small bubbles will grow with additional gas. The initiation of bubbling is related to nucleation (like salt added to beer, which has a considerable excess of dissolved gas.)

This also explains the presence of bubbles – which is a problem. In Zero G they will collect in unpredictable and probably troublesome places. I shut down my test Oxygen generator cell after several hours, because it was obvious that bubbles where forming in the electrolyte. The problem, as I understand it, is that the dissolved gas pressure at the electrodes must exceed the gas pressure in the gas chambers, to drive the required diffusion. This is the reverse of the gradient in the Fuel Cell mode. The higher dissolved gas pressure will always lead to bubble growth if the total electrolyte pressure it same as the gas output pressure. In most parts of the electrolyte, the dissolved gas is a mixture of Hydrogen and Oxygen (plus, in my setup, Nitrogen). In general, a modest excess pressure in the electrolyte chamber should prevent bubble formation (and actually shrink any present). However, my test cell responded to increased electrolyte pressure by leaking electrolyte into the Oxygen gas chamber.

The fact that leakage occurred only on one side suggests a defective seal, rather than an intrinsic problem. However, the manufacturer recommends a very low differential pressure, and this may not be adequate to prevent bubbling. I have received minimal feedback from the manufacturer to date concerning these problems. It will come as no surprise that ”alt.space”, developmental technology is not attractive to industry – so I may receive no answer. There is no intrinsic reason that the electrolyte can not be pressurized and conditioned to avoid this problem, but it may require “reinventing” the alkaline fuel cell!

The separator membranes should not be a problem. Very fine pore, hydrophobic membranes are now common, usually made of expanded Teflon (PTFE). As long as the pores are uniformly smaller than one to two microns, these will hold back water at less than 20 pounds per square inch pressure. Pore sizes smaller than 0.1 micron are used in some processes. The classic material of this type is Gore-Tex. This has apparently been largely superseded by competitive products, now that its patent has run out, and in fact is unobtainable as “Yard Goods”, in small quantity for sewing jackets or experimental work. I will avoid mentioning this unobtainable product in future posts. I have found ULTREX at one internet supplier (www.sewbaby.com) which handles it for making waterproof diaper covers! I just received my order.

This is very important to me, since – as I mentioned earlier – all Zero G systems require careful control of gasses dissolved in liquids (and liquid vapors in the atmosphere). Without this, unmanageable bubbles and droplets will plague every system! (Note that I have abandoned the idea of an ULTREX precipitator, since I can’t envision a way to restrict condensation of vapor to the back – liquid - side of a membrane, and not on the front side also. It works very well as an evaporator, including for distillation). The current system requires degassing of the electrolyte stream. My first set up insured that a lot of Nitrogen was dissolved in this liquid, as well as the Hydrogen and Oxygen, which makes the bubbling problem much worse.

ULTREX and its equivalents promise to hold back water flow at 20 pounds per square inch pressure. (Testing is feasible, with sealing of pinhole defects). This should make it possible to pass the liquid through a separator cell, with a vacuum on the back side of the PTFE membrane. Water vapor will pass through the membrane along with most of the dissolved gases. I knew I would need this kind of separator, and have been looking for Gore-Tex like material. I had hoped I wouldn’t need it so soon!

It is an unfortunate reality, in this kind of development, that progress is often backward. Deficiencies of available products are revealed which must be remedied before the promised results can be obtained. This of course makes scheduling of the work ridiculous, but since no date or funding commitment for an affordable Mars Mission has occurred, elapsed time is not yet a big factor. More important is completing the demonstration that success is likely – when and if anyone cares to go.


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Post    Posted on: Tue Apr 26, 2005 7:59 am
This article talks about a microbial power cell that uses hydocarbonate waste products as fuel to produce hydrogen. It would have the benefit of recycling water while producing hydrogen, might be something that you could use on Mars- not sure it would be suitable for the flight there. It says that the device is more efficient than electrolysis and only a small voltage is applied. Might be worth investigating as it says you can obtain a paper on the device online.

http://live.psu.edu/story/11709

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Post Re: Development Strategy   Posted on: Tue Apr 26, 2005 2:59 pm
rpspeck wrote:
Actually, since campbelp2002 has demonstrated his ability with orbital mechanics, I ask him to check my figures. For a single burn at 6400 km Earth radius, I ended up with just under 400 meters per second delta V - ADDED TO THAT REQUIRED TO REACH ESCAPE VELOCITY - to retain enough energy ("V infinity") for a minimum energy transfer to mean Mars orbit. CAN YOU CONFIRM THIS? GTO (transfer to GEO) takes 760 m/s less than escape, but orbital insertion adds 1496 m/s, totaling 736 m/s above escape - AND 336 ABOVE MARS TRANSFER! So LAUNCH to Mars, is not a big problem.
I haven't checked your results in detail, but it sounds about right. When people say that LEO is halfway to anywhere in the solar system, they aren't kidding!

No, the launch energy required to go to Mars has never been the problem, and NASA has never said that is the problem. The problem is making a space craft reliable enough to last long enough to get to Mars. And the challenges of communication, navigation, entry and landing for such a long flight. By comparison a 3 day trip to the Moon seems like child’s play!


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Post Re: Development Strategy   Posted on: Tue Apr 26, 2005 3:39 pm
campbelp2002 wrote:
No, the launch energy required to go to Mars has never been the problem, and NASA has never said that is the problem. The problem is making a space craft reliable enough to last long enough to get to Mars. And the challenges of communication, navigation, entry and landing for such a long flight. By comparison a 3 day trip to the Moon seems like child’s play!


Thats why we need a lot more of those 3 day trips on reusable hardware to work the kinks out of longer term systems!


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Post    Posted on: Wed May 04, 2005 4:30 pm
Some googling has taken me to this:
http://www.nasaexplores.com/show_912_st ... 0903152844
which says, in part,
"In testing the difference in atmospheric or cabin pressures, here are some historical facts. Skylab crews would go from a ground-based, sea-level launch environment to the 34.5 kPa (5.0 psi), which contained 70 percent oxygen and 30 percent nitrogen, environment of the Skylab cabin and be unable to tell the difference as far as energy expenditure and alertness were concerned. Skylab crews operated at this low pressure and atmosphere composition with only the following subjective notes or observations:

The lack of convection resulted in a warm feeling because the rate of heat rejection was reduced.
The reduced water boiling point caused a cold feeling after showering due to rapid evaporation of water.
Sweat rapidly evaporated during exercise, which helped body cooling.
Lower air density reduced voice projection and made whistling difficult. "

And this:
http://ares.jsc.nasa.gov/HumanExplore/E ... IC017.HTML
Which says, in part,
"No oxygen concentration has been declared as an absolute upper limit for flammability reasons, but design is increasingly difficult beyond 30 to 40 percent oxygen. On Skylab, a 70 percent oxygen atmosphere was used, and nonmetallic materials usage was severely constrained. Crew clothing was made of polybenzimidizole (PBI), a material which was not comfortable for extended wear and was not washable. The walls were anodized aluminum because paints were found to be flammable."

This sounds like flammability is a concern, even if O2 partial pressure is the same as sea level. This makes no sense to me. I always thought flammability was related to partial pressure of O2 and not concentration. I would think that 100% O2 at 1/5 sea level pressure would have the same flammability as 20% O2 at sea level. Am I wrong about that?


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Post    Posted on: Wed May 04, 2005 6:33 pm
Thanks for the information. At least the fire question can be easily studied (with pure Oxygen inside a partially evacuated Plexiglas tube.) I have seen some very contradictory conclusions, but in fact your second (flammability) reference doesn’t mention TOTAL pressure. They may have focused on full 14.7 psi pressures. As I understand it, Velcro – much desired by space crews – has always been a flammability concern, so this would be an excellent test material.

In orbit (micro g) nothing burns very well for there is only the puny process of diffusion to bring new fuel into a fire. On the other hand, “flameless” combustion can exist and be overlooked. In most situations this would have an easily detected Infrared Emission signature, so this is a manageable problem.

Relative to your question, neutral gas buffers carry away enough heat that they do reduce flammability. Thermal conduction changes very little in the pressure range we are discussing. But normal flammability is strongly affected by thermally generated convection currents, and these are radically reduced with reduced pressure (and density), since the pressure gradient forcing hot gasses to rise is linearly reduced with lower total pressure.

Personally, I rather like the feel of Kevlar fabric, which should be hard to burn even in pure Oxygen. At the other extreme, cotton cloth and paper burn beautifully – in normal air – and we use a lot of both with no concerns!


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Post    Posted on: Wed May 04, 2005 7:12 pm
rpspeck wrote:
your second (flammability) reference doesn’t mention TOTAL pressure. They may have focused on full 14.7 psi pressures.
It does mention the 70% O2 of Skylab which is specified in the other quote as being at reduced pressure. So I gather from both references combined that 70% O2 at 5 psi is considered an increased flammability hazard.


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Post    Posted on: Fri May 20, 2005 2:00 pm
Hello rpspeck,

The ISS oxygen generator has failed totally. Is your system ready to fly? Maybe you could save the ISS!

Who am I kidding. Even if it was ready to go, NASA would never fly it until about 10 man-years of paperwork was completed. :(


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Post Bubble Gulper   Posted on: Fri Jun 03, 2005 7:33 pm
We have finally obtained usable performance from our “Membrane Gas Transfer Cell”, AKA, “Bubble Gulper”. This unit removes dissolved gasses from a liquid stream before they can generate bubbles – AND REABSORBS BUBBLES ANYWHERE IN THE SYSTEM! As noted earlier, control of evaporated liquids and dissolved gasses is the main problem with “zero g” systems, because liquid gas interfaces are so unpredictable and uncontrollable. The “Gas Transfer Cell” is also a critical component in our liquid precipitators, for the resultant liquid streams must also have controlled dissolved gas.

Any change in temperature or total pressure in a liquid stream can make dissolved gas “supersaturated”, and liable to form bubbles. Usually this starts at a nucleation center, or at the surface of a preexisting bubble. “Vacuum bubbles”, the result of zero hydrodynamic pressure “cavitation”, quickly become loaded with dissolved gas.

Bubble formation in the body is of course the cause of the “Bends” – decompression sickness. Prevention of this for high altitude exposure, or spacesuit use, usually involves pure Oxygen prebreathing (often for hours) to replace the difficult to remove Nitrogen from both blood and body fluids, with Oxygen, which is automatically removed by ordinary metabolism. A Russian report suggests that the low incidence of “Bends” with spacesuit use – even with marginal prebreathing time – is the result of low mobility with current designs. This reduces the likelihood of cavitation in joints produced by abrupt motions, and the accumulation of Nitrogen likely in these “vacuum bubbles”. This suggests that far longer (or continuous) Oxygen breathing will be necessary when high mobility EVA equipment is developed.

The accumulation of bubbles also causes “Air Embolism”, a severe medical problem when large bubbles in the bloodstream block arteries, and “vapor lock” in a gas engine. Air bubbles can totally block flow through a fine filter, and can radically degrade the effectiveness of a liquid cooling system. Bubbles totally stop local electrochemical action (as in an electrolysis unit) when they keep chemical solutions from reaching the electrodes.

Once gas is removed from a liquid in the “Bubble Gulper” (Gas Transfer Cell), this circulating fluid becomes a “liquid sponge”, ready to soak up more gas from any pockets in the system. Once picked up at a remote bubble or pocket, this will also eventually be transferred through the Gas Transfer Cell membrane into the pumped vacuum system. Some liquid vapor is of course picked up at this membrane as well, depending on the liquid temperature. Porous Teflon membranes permit gas transfer while completely blocking liquid flow through the thin film even under high pressure.



I confess that obtaining usable performance for this unit has been more difficult, and time consuming, than expected, but it is working. Perfecting a flight ready version of this unit, for use at multiple points in the life support system, will take additional work. But no “show stoppers” have appeared to stop the development of a compact life support system for deep space missions, and none are expected. Even the acquisition (and modification) of parts to make closed circuit respirator masks has been a slow (and expensive) process. But they are also going together. Most of the necessary gas analyzer cells, pressure and flow sensors are now operational as well.

I doubt that any progress has been made toward funding a low cost, Mission to Mars, but progress is being made on the necessary life support systems.


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