New Mars Forums

tahanson43206,

The basic calculations used look correct to me, but real gas effects at the extreme temperatures involved are going to measurably affect the rocket's performance, so I'm curious about what our refined performance figures will be.

The actual specific heat of Hydrogen, for example, is going to affect the energy input requirement:

https://www.researchgate.net/profile/An … rature.png

Edit:
NASA Polynomial representation of molecular specific heats

This paper might be easier to read and access for you:
NASA Polynomial representation of molecular specific heats

Scroll down to the section entitled "Gas Phase Heat Capacity (Shomate Equation)":
NIST Chemistry WebBook - Hydrogen

Calliban,

A country that cannot make its own steel products for construction can hardly be described as self-sufficient.  There are clearly other considerations at play besides the absolute lowest cost achievable, such as not handing money over to countries like Russia and China, which are exclusively run by people who engage in bad faith business practices.  What happens to the UK's defense industry, for example, when they cannot make their own steel forgings?  How many times do the lessons of WWI and WWII need to be re-learned?

I don't want to employ Americans at $5 per hour to make things, but our Democrats recently imported 10 to 15 million people who can't speak English, but also need jobs in order for them to become a net benefit to our economy.  I never agreed to that, they just did it without our consent, which is one of many reasons why they were booted out of office.  My hope is that these illegals will become American citizens, be paid a living wage after going through the process of learning the language and marketable skills, and that the tariffs being imposed will cut the anti-social business practices of our wealthy elites off at the knees, so that these new prospective Americans can also live long and prosper from the American experiment.

Do I think it's desirable to pay one of my fellow American workers more money for his or her high quality labor / product so that he or she can afford to raise a family and own their own home?

Let me think about that...  Yes, I believe that's exactly what I've wanted for quite some time now.  I'm writing this on an Apple computer that was made in 2010.  If it cost me $3,000 vs $1,500, but the end result was that I handed my money over to my fellow Americans, rather than Chinese people jumping off the roof of Apple's FoxConn factory in China because their living conditions are so horrific, then I can live with that.  I won't lose any sleep over the fact that I have fewer meaningless choices, or can't afford to buy a new computer the instant a newer model arrives in stores.

Peter Zeihan's beliefs about the tariffs are indelibly colored by his politics.  He still thinks America should be involved in Globalism 2.0.  He runs his own little program in his mind, which auto-deletes any evidence that disagrees with his beliefs, because he's a leftist.  Leftists have only two factory default responses to any scrap of information that disagrees with their inner monologue about the way the world works.  They either totally ignore the information, or they totally freak out.

Take RobertDyck, for example:

What is he so upset about?  He routinely voices his utter disdain for America and Americans, and blames American influence for what his country's politicians do or don't do.  You'd think he'd be thrilled that America and Canada are going to run their own separate programs.  His country is finally getting the opportunity to prove just how superior they are to Americans.  He tells us all the time how great Canada is.  This is the perfect opportunity for him to put his money where his mouth is.  He can continue to be "all Canadian, all the time", with no undue influence from yucky Americans.  I would think he'd be stoked.  What is he doing instead?  He's whining endlessly about President Trump.  He can't think of anything else more important to do with his time than to complain about something that is unlikely to ever affect him.

Canada can't help rebuild American manufacturing, and neither can Mexico.  Only America can rebuild American manufacturing.  The smarter people in the room have already seen the writing on the wall and decided to get with the program, rather than fight tooth and nail against it.  I want Canada to rebuild Canadian manufacturing for Canadians.  I want Mexico to rebuild Mexican manufacturing and agriculture for Mexicans.  These are not mutually exclusive end goals.  The people of all nations can benefit from maintaining their own self-sufficiency.

America is not moving towards yet another form of co-dependence.  We're all going to have to stand on our own two feet, for the good of everyone, but especially our rapidly deteriorating middle class, which was historically the labor force, thus the true engine of our economies, and the creators of the next generation of works and innovators.

Is this self-sufficiency idea really so scary to everyone else?  If so, why?

tahanson43206,

23 trillion dollars have been siphoned out of the US economy through the trade agreements our leftists have made, which has decimated our middle class.  The only predation going on here is the impoverishment of the American middle class by wealthy coastie liberals who gain control over the means of production, only to destroy the factory or send their jobs to other countries.  Reshoring manufacturing and offering to buy out otherwise failing nations, which are already contiguous with the US, is NOT predation if the entire end goal is to return them to prosperity and to become stronger as a nation.

We would no more dictate life to Canadians who join America than we do to Texas or California.  America's federal government does what it does, often to the dismay of everyone, but the many states are largely operated locally and independently of the federal government.  Canada would still be Canada after joining the US.  We're not all going to rush to live in Canada if they become part of the Union.  Nearly all of their laws would continue to remain in full effect after joining America.  Only some errata related to the parliamentary system would be modified, which has far more effect on the liars, I mean lawyers, who run both our nations, than the average citizen.  Claiming that the nature of Canada would change is like claiming that the nature of Texas and California would change.  Oh, really?  Where's the evidence for that?

Texas isn't "preying upon" California.  The radical leftists who have made life in California so intolerable that people with the ability to leave are choosing to get as far away from their insanity as they can manage.  Texas is offering California's economic refugees a chance at a better life here in Texas, so that's where many of them end up.  Some people from Texas still choose to move to California, and that's the great thing about our system.  We allow our people to do that.

We would do the same thing for all Canadians and Greenlanders opting to become Americans, unless you want to make the case that the average American is now less well-off than the average Canadian, in which case your insinuation that we are somehow preying upon them doesn't seem to hold water.

So you can hear it from the former US Trade Representative, instead of me:

Bob Lighthizer: Everything You Need to Know About Trump's Tariffs and Fixing America’s Working Class

All the former British colonies have common cause and share common interests.  America is a special case, being a former colony that generally considered themselves Americans first.  We have our own unique ways of doing things that don't neatly fit into the British system, whereas Australia, Canada, and New Zealand are more neatly-aligned with the British system than America ever was.

As it relates to defense, our interests are generally congruent with the interests of Australia, Canada, and New Zealand, but even there we will encounter "edge cases" where we don't align, which is why we all need our own defense industrial bases to draw upon.  If Australia, Canada, or New Zealand were ever attacked, you're too silly to take seriously if you actually believe that President Trump won't support your nation in time of war, but the way the American military does things may not be the way the rest of you want them done, hence the reason for all of us having our own credible local defense.  All of your nations continue to receive full access to American military tech and full technical support.

When it comes to joint defense projects like the F-35, both the American government and Lockheed-Martin thought that every participating nation would build their own F-35 factories.  Only the Italians ever followed-through by building their own factory.  Yes, it cost them some money to build, but that money created local jobs, local taxes, and locally-produced F-35s tweaked to the desires of the Italian military, to defend Italy.  For some reason, everyone else said, oh no no no, you're going to produce the model that the Americans military gets.

Lock-Mart said, "Okay Uncle Sam, it's your call since you're paying the bills, but now there's a new deal on the table.  We have to produce everyone else's jets as well, and we cannot appear to favor supplying our military, so all of our prospective Air Force / Marine Corps / Navy F-35 pilots are going to have to wait to receive their new jets while we fill those additional orders that we never agreed to, because we already had a deal regarding where the jets would be produced, which was not at Fort Worth.  All of you collectively reneged on our previous deal, so we never built additional capacity at our F-35 factory to produce additional jets for partner nations.  We cannot wave a wand to create extra production capacity, and you're not providing more money to expand production capacity, so we're stuck with our present production rate."

That's yet another example where globalism hurt all of us.  Rather than proceeding with the build-out of the necessary local infrastructure, we have parts suppliers from all over the planet shipping parts of the jet to the factory in Fort Worth, because that idiotic globalism idea stopped them from building their own local fighter jet factories.  After the jet gets assembled, it then has to be flown half-way around the world to wherever it's going to be used, and if something goes seriously wrong, then it has to be flown back to the factory.  That idiotic system slowed down F-35 production for everyone, no efficiencies of any kind were achieved, and it made each jet more expensive, not less.  That, ladies and gents, is retarded.

The Net Zero Delusion Part 1: Mark Mills

These green energy machines can be up to 75% efficient at converting stored energy into useful work output, rather than 50% efficient as is the case for modern diesel engines, but where I'm from a 25% net efficiency increase, well-to-wheels as they say, doesn't come close to resolving that enormous embodied energy increase of 1,000%, into the required metals and minerals, never mind 7,000%.  It's a gross distortion of energy reality, which is why net hydrocarbon fuel energy consumption has only decreased from 86% of the total global primary energy supply, to 84%, while the total quantity of hyrocarbon fuel consumed has drastically increased, relative to when this non-transition started.

That means all these electrical / electronic green energy machines are horrendously inefficient when total energy input per unit of energy output is considered.  They're so bad at total energy efficiency that it's frightening to consider that anyone actually thought these things were going to replace combustion engines.  It's pure idiocy wrapped in the flag of environmentalism and climate change, as if that somehow makes ignoring the fundamentals of economy an "okay thing to do".

Real economy is the economy of energy / labor / materials consumption.  Real capital is a derivative product of the confluence of consuming energy, labor, and materials to do something that the people think is worthwhile.  We've spent somewhere between 5 to 10 trillion dollars to permit green energy machines to augment, rather than replace, 2% of the total global primary energy supply.  There has been a net consumption increase in all forms of energy to achieve this, most especially hydrocarbon fuels.

Edit:
Wind and solar currently account for 3% of our total global primary energy supply.  That is quite an accomplishment, and I don't want to downplay the achievement, but to think we're going to reach 70% of the total energy mix in the next 10 years is grossly delusional.

RobertDyck,

Adding up all the trade deficits that the US has with all the nations we trade with, and it's no longer a rounding error.  That is part of why President Trump was re-elected to office.  If all the trade deficits the US has with other nations only run in a direction unfavorable to the US, every single year, then eventually the money is gone and the manufacturing workforce is decimated.  That is precisely what has happened to the US, because our Democrats have devised a system that is ultimately self-destructive.  We're moving away from that system of trade, because it no longer makes sense for the American worker.  When that system was devised, the Democrats told us how much it would benefit Americans.  It did the exact opposite of what they claimed.

Every trade policy our neocons and neolibs (these people don't behave like actual Democrats or Republicans) have come up with during my lifetime has done the exact opposite of what they've claimed it would do.  We, the ordinary American people, are sick of the nonsense by our monied class.  I don't care how cheaply they can buy foreign goods and materials.  They ought to be doing business with their own fellow Americans, even if that means they can only afford one super yacht instead of two.  We want our own industrial base, which includes our own mining, energy, heavy industry, tech manufacturing, and medicine.

Let's use a concrete example that I think is asinine:

Canada produces lots of heavy crude from their oil sands, which they pump into the US.  I think it's great that Canadians have such an abundant supply of oil and natural gas that they cannot even use all of it.

Does the US really need to consume Canadian crude when Europe is hurting for oil and gas, or should they have built pipelines to pump Canadian crude to tanker ships bound for Europe?

We raised the local energy prices on people here in America, who could least afford the price increases, by choosing to ship our NGLs to Europe.  Why did President Biden's administration do that to his fellow Americans?  If Canada had their own pipelines, Canadians would've profited handsomely from what was going on in Europe, and Canadians are tied into Europe in a way that virtually all Americans, apart from our coastie champagne liberals, are not.  Our coasties were smugly pleased with themselves while their less well-to-do American brethren suffered terribly.  Frankly, I find their behavior repulsive.  Canadian energy prices wouldn't have gone up a penny because they have an enormous supply glut that they require foreign purchasers to consume.

I don't blame Canada at all for what transpired, but I do blame our leadership for enabling that state of affairs.

American crude oil refineries should have made the switch to consume light sweet shale oil at least a decade ago, rather than heavy crude.  We should have converted our diesel engines to run on natural gas liquids, which we have coming out the wazoo.  If we do need heavy crude for certain products, such as tar for roads, then we do have our own oil sands and heavy crude wells here in America, which our own neocons and neolibs refused to allow American companies to start using.

Why is it that we should not consume what we locally produce?

Why is it that Canadian crude should be pumped half-way across America, only to be sent back to Canada and Europe as refined products, when Canada has all the people, know-how, and money to refine and pump their own products?

Does any of that make any sense to you?

Why have we made ourselves so co-dependent in such absurd ways, and worse than that, co-dependent on countries and people who hate America?

It makes no sense.  It was yet another attempt by our self-serving globalists to exploit people, rather than being forced to pay their workers living wages so that they could continue to raise the next generation of Canadians, Americans, Chinese, etc.  It's asinine and ultimately self-defeating.  It only works in a wildly distorted market where national security and prosperity interests are subservient to multi-national corporations.  Our security interests either align or they don't.  Trade should never be part of security decision making, and wouldn't be if nations were self-sufficient and corporations were not allowed to behave in ways that violate national sovereignty and security.  If our corporations or their monied share holders are not allowed to place their financial interests ahead of national interests, and we all have our own infrastructure so we're not co-dependent, then we can choose to go our separate ways if our interests don't align, there's no hard feelings over it, and no incentive to start or maintain wars over foreign resources when domestic production is sufficient to cover domestic consumption.

That is how a well-functioning economy would work, and global trade would only take place when and where it made good economic sense, with the express understanding that the American government isn't going to start a war merely because some trade-based company made a bad financial bet by offshoring their operations to a foreign country.  That should apply to oil, computers, cell phones, washers and dryers, everything.  That kind of foreign policy would do more than anything else to discourage wars.

We'd still have bad actors like Russia, Iran, China, and North Korea, but their ability to adversely influence the global economy would be functionally nonexistent.  What would China be able to influence militarily without their hundreds of billions of dollars of international trade?  Where would the Chinese get the computers to design and operate advanced weaponry, had we not given all that stuff to them?  It was pure idiocy to not anticipate what they would do, because it's the same thing that the Russians attempted to do with the handful of advanced computers they obtained from western sources, which they were never able to locally replicate.

What is most notable about that solar thermal concept, is that the 1,041s Isp value thought to be achievable using the materials tech of 50 years ago results in roughly a 50% payload mass fraction.  That means only 50% of the entire vehicle's all-up wet mass is part of the propulsion system, and the time required to put the vehicle on a TMI (Trans-Mars Injection) flight trajectory, is reduced to around 40 days.

For the 500 passenger 650,000kg interplanetary transport vehicle (ITV) I anticipate will be powered by this propulsion system, that means the propellant mass is around 450,000kg of H2 to provide 4.8km/s of ΔV over 40 days of thrusting, culminating in either a circularized geosynchronous orbit or TMI maneuver.  The anticipated dry mass of the vehicle would be around 750t, which includes the ITV, the mylar parabolic mirrors (if fiber optics prove to be mass-unfavorable) that collect and convert photonic power from the Sun into thermal energy, and multiple CFRP H2 propellant tanks, which must be fueled on-orbit by a Starship tanker variant.

Roughly speaking, 450t of LH2, at 70.85kg/m^3, is equal to 6,352m^3 in volume.  For comparison purposes, the SLS core stage capacity is about 3,517m^3 between the LOX and LH2 propellant tanks.

Current state-of-the-art Aluminum-Lithium alloy cryogenic tanks would weigh 49,649kg for 6X 10m diameter tanks with a capacity of 634m^3:
STRUCTURAL DESIGN AND SIZING OF A METALLIC CRYOTANK CONCEPT

An equivalent composite cryotank from Boeing had a final mass of 6,696lbs, so 30,373kg for all 10 tanks:
STRUCTURES AND DESIGN PHASE I SUMMARY FOR THE NASA COMPOSITE CRYOTANK TECHNOLOGY DEMONSTRATION PROJECT

The IM7 fiber used by the Boeing / Lockheed-Martin / Northrop-Grumman cryogenic composite demonstrator tanks, which were tested with LH2, is much weaker than Toray T1100G fiber (another fiber tape system used by automated tape layup machines), but the demonstrator program used government furnished fiber and resin intended for consistent design and testing purposes, so may not be representative of flight-weight tanks.

That leaves 69,000kg of mass allocation for the solar thermal collectors and engine(s), in order to arrive at an all-up wet mass of 1,200t, to push the 650t ITV into geosynchronous orbit, whereupon a smaller onboard propellant supply would complete the push to escape velocity.

RobertDyck,

Garry Kasparov doesn't speak for Russian leadership and he cannot know how 143M+ Russians feel about the war in Ukraine.  I'm sure some support it while others hate it.  I would be willing to bet almost anything that how you feel about the war is directly proportional to your involvement in it.  I've never known anyone who was enthusiastic about the proposition of getting shot at again.  Some random Ukrainian woman doesn't speak for the Ukrainian government or people, either.  Why do you even bring up these irrelevant anecdotes?  Similarly, I don't ask the neighborhood football champ how he feels about spending more money on the space program vs the food stamps program.  I will listen to what he has to say out of common decency and respect for others, but then I consider the source of the opinion and knowledge of the person I'm talking to.  I seriously doubt either of the anecdotes from those two individuals is based upon breadth and depth of knowledge about public opinion on the war in Ukraine.

I'm not looking at personally-held opinions of non-decision-makers.  I am taking the publicly stated and reiterated policy positions of elected or appointed European Union and Russian leaders at face value.  Kaja Kallas is the European Union's foreign policy minister.  She's going around telling people she wants to break up Russia, and that the European Union should be the ones to do that.  I'm not a Russian and I'm sure as hell not Putin, so I can't pretend to understand their interpretation of those statements, but I would imagine that if Kaja Kallas went around telling people she wanted the European Union to "break up" the United States into a bunch of smaller countries, that would go over here in America about as well as a Lead balloon.

Glenn Greenwald is merely reporting on what European Union leaders have publicly stated.  If you think that is "crap", then it's not Glenn Greewald's crap, it's Kaja Kallas and Ursula von der Leyen's crap.  Give credit where credit is due.  Try addressing the message for once, instead of the messenger.  Please try addressing what Kaja Kallas and Ursula von der Leyen are telling people in public forums about what they think European Union policy should be towards Russia.  If you have a problem with what Kaja Kallas or Ursula von der Leyen have stated, then focus your outrage on them, rather than Glenn Greenwald.

I believe I've posted something like this before, but here's another paper from NASA on advanced Carbon / Carbon-Ceramic rocket engine main combustion chamber and nozzle design work going on at NASA:

Extreme-Temperature Carbon- and Ceramic-Matrix Composite Nozzle Extensions for Liquid Rocket Engines

2,343C is equal to 2,616.15K, so not quite where we need to be, but much closer than most metals.  To be clear, UHTCs (Ultra-High Temperature Ceramics) are required to make this work at 3,200K, our target chamber temperature for 1,000s of Isp using pure LH2 propellant.

Carbon-Carbon Nozzle Extension Development in Support of In-Space and Upper-Stage Liquid Rocket Engines

They tested these nozzles with LOX/RP1, LOX/LCH4, and LOX/LH2 propellants.  The entire point behind development of this tech is that the major parts of the engine are much lighter than Copper-Nickel alloys, Carbon is easier to come by than Copper and Nickel, they're not regeneratively-cooled, they're 3D printed so they cost less, and they're reusable.

Edit:
For comparison purposes, the 3,200K / 2,926.85C chamber temperature required to achieve 1,000s of Isp is most similar to the flame temperature created when MAPP gas is combusted with pure O2.  Pure O2/H2 flame temperature is around 2,660C, and pure O2/CH4 flame temperature is around 2,810C.

RobertDyck,

Secretary Baker is one of the people who made statements to the effect that NATO would not expand eastward, which was then reiterated by every NATO member nation leader who actually mattered.  You can continue to play this game of pretend with history, but Russia is not fighting in Ukraine over pretend actions on the part of NATO.  Thanks to FOIA, we have multiple documents and statements contrary to what is now being claimed.  Gorbachev was not the only person or decision maker present at those meetings.  Nothing you've stated here has addressed those documents and statements.  Either all those leaders from the US, UK, and West Germany were lying, or we have a very convenient way of interpreting what they actually stated before the Soviet Union officially dissolved.  Opinion pieces from opinionated history revisionists aren't equivalent to what was factually stated and recorded, in writing, by our own leaders.

You don't think the Soviet Union was the only nation to ever knowingly push objectively false propaganda, do you?

Putin is by no means the only historical revisionist hard at work here.  A lot of people from both sides are trying to re-imagine history as it never was.  Putin's claim that Ukraine was always a part of Russia is particularly absurd, as are our claims that we never promised not to expand NATO.

Our media makes their money pushing the narratives that their benefactors tell them to push, plain and simple.  That's why they've lost nearly all credibility in the eyes of the general public.  The leftists don't even believe them these days, despite the fact that nearly all of our media and pop culture is leftist in nature.

Yes, I want to stop the war because Ukraine is not going to win anything, but it absolutely could lose everything.  As bad as Russian demographics are, Ukrainian demographics are worse, and there are a lot fewer Ukrainians than Russians.  Leftists still don't know how to count.  All the former Soviet bloc nations could simply decide to rejoin Russia of their own accord, absent any mere talk of war, but their demographics are still terminal and won't change unless their living conditions improve to the point that the people living there see some point to raising a future generation.  Russians are opportunists and decided they could take advantage of the situation, but that hasn't gone well for them.

If you think the Ukrainians are going to fight for Russia, you're as mad as a hatter.  Ukrainians wouldn't piss on the Russians if they were on fire.  Poland's military is a bit short on manpower, but they have more functional fighting machines than the entire Russian Army at this point.  Lithuania, Latvia, and Estonia are more or less split on whether to continue with NATO or rejoin Russia.  The issue is a matter of national survival for them.  The leadership of the mainland Europeans spend more time squabbling like children and dithering than doing any real fighting.  They talk a good game, but won't put their money where their mouths are.  The older generation from the Soviet bloc countries remember their "glory days" fondly, despite the fact that there was nothing glorious about being dirt poor cannon fodder for Moscow.  I guess it's hard to not remember your youth fondly, however miserable an existence you led.  In any event, Russia has all but exhausted their conventional military capabilities in Ukraine.  Attacking Poland would be suicidal at this point.  Putin is many things, but he's not a kamikaze.

We can continue this obvious stalemate to appease the obtuse amongst us, or cut our losses so that more Ukrainians can live to fight another day.  We already know where we line up on this matter, so now it's a contest of will.  President Trump offered to put American civilians directly in the line of fire, via the minerals deal, to discourage Russia from future military adventurism in Ukraine.  I don't think President Zelensky is going to receive a better deal than what's already being offered, and if I were him I'd be way more concerned about the well-being of my countrymen than whatever Russia has stolen from Ukraine.  National borders move throughout history.  Land is replaceable.  Lives are not.  Unless you're personally willing to pick up a rifle and go fight for Ukraine, I would reconsider the gung-ho attitude on fighting the Russians over a patch of dirt that's traded hands a half dozen times during the past century.

RobertDyck,

The Russians were given a promise of no eastward expansion of NATO, and I posted the link to all the relevant documentation, in this very thread, detailing the statements and notes made by all relevant western global leaders at the time the Soviet Union was dissolved.  You are the one repeating propaganda here.

Dr Clark,

Unless you're privy to quite a bit more of the inner workings of the Starship program than everyone else here, that assertion is backed by nothing but a personal belief.  You've convinced yourself that you know something on the basis of tidbits of information online with little greater context.

This reminds me of the time you told me about an Aluminum alloy "stronger than Carbon Fiber"?  The way you came to that conclusion, which was also based upon something posted online, is remarkably similar to what I see here.  You simply would not let go of that belief, despite the engineering data I provided.

If you've now convinced yourself that "just one man" is somehow preventing Starship from completing a successful orbital test flight, then I think you're making yet another logical leap, on the basis of what someone else posted online.

How is that an acceptable substitute for knowing something about what the engineers at SpaceX are actually doing?

Elon Musk clearly isn't the only person there who is doing things and making decisions at SpaceX.  You may have convinced yourself that he is, but I can promise you that SpaceX would never have made Falcon I fly if that was actually true.