AngelLestat

Heh, yeah it's just an analogy that apparently for some weird case, everybody seems to enjoy But I dont think the stresss would be an issue, if you scale up, that is a lot more of air you add by volume, so you need to fulfill with steel and all kind of heavy stuff, but then is not easy to fit 2000 people, yeah is not easy. But the point I want to make, is that is more an issue of will and determination, than a tech or physsics limit. In fact you dont even need make practical test for each step and each material to see what may be the best. Supercomputers right now are so good simulating conditions that you can test several configurations and select and discard options a lot faster and cost efficient. Also you dont need come out with the best reactor ever, you just need something that it works inside the parameters you look for. Ok, said exactly what part of the whole system seems the most complicate and why you think it can not be done. Then if someone of here (with our limited knowledge) come out with a possible solution, it means that even us we may have an idea of how to solve problem by problem, which a group of experts for certainly will, the devil is on the details, that takes time. But not so much as NASA always show. haha. that was some pro derail right there Well I never defend that 39 day nonsense. But I guess 100 days is something that is a lot easier to achieve than 39 days, and still very promising to change and improve all our solar system activity, if we have that ship in space, we can do wherever we want, manned mission to mars, venus, titan, europa ice submarine, etc. And you can always reduce the payload to achieve higher deltav. So the question is... we stay for always with chemical propulsion or we make once for all the obvious step? They are planing right now fly-by to the ice giants that might take 40 years to complete, just to get some telemetry and pictures. You really want wait that time for each new mission? In fact, nobody takes into account the singularity, so all those long term ideas does not have a bit of logic.

To everyone else? you did a poll? I just saw Rune and you with all kind of concept issues. Name a submarine able to transport 2000 people, you cant? then according to you: "it can not be done... we dont have the tech"But the tech is similar, we just need to scale up, in fact a submarine so big, it will be more cost efficient by passenger. But we dont have one.. why? Because we never need it. So first... try to fix your "logic" if you want to make a point. Ok, I need to explain again what a reactor means? "The reactor" is the machinery component where the fission takes place. Of course you need to connect it to the "Heat Engine", and the Heat engine to the colling system. Now you need to move the heat from the core to the heat engine, so you may use supercritical co2 or helium, water, salt or a heat pipe that is in direct contact with the fission materials, so all that part of the system is also called Reactor, which may include a pump and a heat exchanger connected to the "Heat Engine" (which is not include in the Reactor at least is in direct contact with the fission material or through a fluid). For what I see, all those things that you Name.. produce electrical power.. so if produce electrical power then they have a Heat Engine and a colling system included. So they are not Reactors, they are "space reactors power systems" Also, the density of a reactor, decrease with the increased power, the same as the Vasirm engine, at 100kwe has a density of 30 kg/kw, but at 10Mwe it has a density of 2kg/kw. See the difference?

This topic already consume me a lot of time, but here we go one more time. Can you quote me in what part I seems to not understand that? Just one time I said that you needed 12 mw without noticing that it was electric, but in the next post I said, ok, in that case is double that amount for thermal. ??? what? hahaha you are desperate. I never mention ammonia, so not sure how you reach that conclusion? Again, please quote me to see where I am wrong. I talk about combined cycles since my first day in this forum, you can use the advance search tool to check it. The one you said is kalina, the order for temperature is Brayton–Rankine–Kalina in case you want a triple cycle. But you can have just 1 cycle, which in space it is advisable due how hard is to get rid of the heat and the problem to add more complexity. 20 kg by kw? really? I guess I can build something with wood using my own tools and come out with better density than that. This is the main evidence that you dont have a clue. And of course you dont want a quote war, a compilation of your answers showing all your "knowledge" will not look nice. So you will ignore my answer and keep talking about refuelling in LEO. I already know that, I detailed here http://forum.kerbalspaceprogram.com/threads/132918-39-days-to-Mars-possible-now-with-nuclear-powered-VASIMR?p=2178215&viewfull=1#post2178215 The 100kw electric in that point means nothing, they just need only 100kwe in that rocket, the rocket use thermal as propulsion, so why you will convert all to electric? But that reactor produce 100mw, that is the main point, a reactor designed for electric conversion will weight a bit more, and a lot more the whole system (reactor + radiator) 100 days to mars is the best using vasimr, your reactor power may be just 50mw (depending the payload) Take into account that a thermal nuclear rocket to transfer the same payload in the double of time will require 1000 mw. Is in the graph from one of the vasimr papers that I show, at low powers, vasimr engine density increase a lot, the best is reaching 10mwe. If we measure this according to NASA developing time, then it will take 30 years. There is nobody more slow and less efficient than NASA. But if the money is at Elon Musk hands and someone ask him (build us a vasirm tug in space to transport cargo to mars), he will do it at 1/3 of the cost and in 6 years. Why? because all the things we discuss are all solvable just using the right materials and clever design, the solutions are not "hard tech" that we need to invent a new material or a new physsics law to do it, you just need to sit down in a chair and start to design it.

Forget about lift one min so we dont make this more harder to explain. In the picture that I gave you is easy to see it. Is all about pitch angle and direction of rotation, you can not keep the same pitch (or low angle pitch) once your engine stop, because you will fully stop the rotation and it will start to rotate in reverse (because the air flow change, now the wind comes from below.) But you dont want to fully stop the rotation and wait until start to rotate in the other direction, so you change the pitch to negative, this way you keep the direction and energy in the blades after you are close to ground, at that moment you change the pitch again to get lift. "Autorotation is permitted mechanically because of both a freewheeling unit, which allows the main rotor to continue turning even if the engine is not running, as well as curved main rotor blades such that when the collective pitch is fully down the inner part of the blade has negative pitch relative to the horizontal plane and can be spun up by the relative wind. It is the means by which a helicopter can land safely in the event of complete engine failure. Consequently, all single-engine helicopters must demonstrate this capability to obtain a type certificate.[5]" https://en.wikipedia.org/wiki/Autorotation http://www.rcgroups.com/forums/showthread.php?t=491271 In other words, the only way to accelerate the rotor without stop it, is to change the pitch, why? because the air flow is inverted, now it comes from below.

Ok, now I understand how autogyro works, I dint notice that in the video he take off with high wind in front. So it only use the back propeller to takeoff and the top blades work as a wing. But about autorotation pitch I am right, after all I was the first (I guess) to comment on autorotation in the forum. The pitch needs to be negative to keep harvesting energy (at the same time than lift) until you really need it when you are close to the ground, so you inverted again. Of course if your engine stop a few meters above the ground, then you dont invert the pitch, just land with the blade energy. https://en.wikipedia.org/wiki/Autorotation

In addiction to K2 words, if you read the FAQ, it said that the "bike" will come with parachutes (maybe 4 small parachutes in the corners, and the pilot may carry one in the back. This thing has 4 engines, and I guess it would be able to flight (or descend slowly) with just 3. The pilot does not need to learn the autorotation procedures. Also not sure why you said that autogyro is always autorotating? To autorotate you need to invert the pitch (if you are high enoght) The autogyro is more dangerous close to people than this "bike" will be. In the FAQ said that the rotors will come with a safety mesh to avoid hands or thing big enoght to crash with the blades. My only doubt it is what would be the best engine type selection and energy source configuration. But even with just 20 min, I think it might be a lot of fun and even usefull for other activities.

The Clan of the Cave Bear New tv series (currently in production) based on the famous saga "Earth's Children" written by Jean M. Auel. I could not believe it when yesterday someone told me that the pilot for this series was being filmed. This is one of the best book saga that I have read, but I was a bit concern, this is not an easy adaptation, but after I read about the team behind this production, all my concern disappeared, it has all the ingredients for the success. The project is a co-production of Fox 21 and Lionsgate in association with Imagine Television and Allison Shearmur Productions. Exec producers are Ron Howard (Apollo 13, A Beautiful Mind, Rush), Brian Grazer, Allison Shearmur, Linda Woolverton, Francie Calfo and Auel. Woolverton, whose credits include (Maleficent, Alice in Wonderland and The Lion King) will pen the pilot. “I’ve always admired Jean M. Auel’s timeless work,†said Rob Sharenow, Lifetime’s exec VP and general manager. “With this visionary creative team behind it, this project has it all  epic storytelling, great characters and a unique world that’s never been explored on television before. This is exactly the type of top-tier creative talent and great stories we embrace at Lifetime.†This is not the trailer. Millie Brady will play Ayla, looks perfect for the role, but she will need a more athletic look by the next year. A picture that she took from the set. Rest of the cast: http://www.imdb.com/title/tt3864098/ An scale reference of a prehistoric Bison for actors, Ron Howard in front. About the books: This book series has sold 60 million copies globally and all six books have been New York Times bestsellers. To compare; Game of thrones book series reach that number only after its 5th season. The name of the saga is "Earth's Children", the first book is "The Clan of the Cave Bear" (1980), the historical story takes place around 28,000 years ago, it centers on Ayla, a Cro-Magnon (modern humans) girl who is homeless and orphaned after an earthquake at the age of five. The Clan (a group of Neanderthals) find her almost death, Iza the medicine woman, decides to save and adopt her, but Ayla life will not be easy, she is a child of the “Others.†As Ayla matures into a young woman of spirit and courage, she must fight for survival against the jealous bigotry of Broud, who will one day might be clan leader. (first book plot) The last book was published in 2011. I love the saga, so I strongly recomend the books for those interested in a new reading, maybe it does not have the best plot ever or the best writing skills, but I remember that after reading some chapters, I couldn't bear to look to the city, even with all our comfort, I just wanted to keep reading to be reabsorbed into that world. This series also help me a lot to understand many misconceptions that "we almost all have" about prehistory, we tend to forget that before Romans or the Egyptians, the world also spinning, we dint have the big civilizations, but it was also people with a lot of great stories to tell, in a world full of life and dangers, under an ice age where 2 different human species will cross their destiny. About the author: Jean M. Auel began extensive library research of the Ice Age for her first book, we need to notice that the only books she wrote, was the 6 mentioned here. He focus her whole life to this story. She was praise and criticized by field experts in matter of the descriptions and predictions she did in her story. But eventually, new studies came, and mostly all critics was proven wrong, she wrote things that science was able to confirm in all these last years. This was not luck, she wanted to be accurate in the description of that age, so she traveled for the whole world visiting all the archaeological sites, talking with all the field experts and analizing evidence and theories. The plot, action and drama from the first books was great, but with the last books was in decline, maybe due the author wish to describe all the things she knew and her advanced age (+75) that might reduce her taste for drama and action; which can be easily solve in the tv series. About the 1986 movie with Daryl Hannah. There was a movie of the first book in 1986, but it was a failure due many reasons. First is impossible to try to resume the first book into a movie, you need at least 10 episodes, which is something that we might see in this series. The movie budget was low, the special effects not upto the task and the first book is the most difficult to adapt from the whole series, this is because there is not spoken languege, they communicated mostly by complex signs, body language and some words. In the book is easier, because you know what they said, but in a movie you will need to add suptitles or a voice in off, or nothing as they did in this movie, where all the complexity of the characters was loss. But I have not doubt they will manage to solve this issue in the series. I have not doubt that the pilot will be approved to show green light for the first seasons, this will be as a breath of fresh air from all other series which are a repetitive dance of cliche and common plots.

for such small production, is a very good movie. Lately we have an invasion of AI movies, to name a few: Transcendence, Automata, The machine (2013), Chappie, humans (series), etc These last 3 years, the amount of AI plot related movies double. - - - Updated - - - I dont remember that scene, I saw it 3 months ago. One of the thing I like it, is when he ask him, if a turing test would be valid here, knowing from start that she was an AI, but he dint know that the servant was an AI too.

Let me translate that for you: It does not exist, it means that never was builded or designed for that specific task. It does not mean that we dont have the technology to build it. Once you know what are your requirements, you design it and build it. The efficiency of the reactor is mostly given by the radiator that you use, if you dont care about the amount of energy left after waste, because that means reduce cost in radiators and your energy needs never was big since the begining, then you are perfecty fine with 20 %. Remember that without vasimr, nuclear reactors to produce electricity are kinda useless in space. Ion engines does not have a good thrust and their performance is very bad when you try to scale them. The amount of energy needs for other task can be perfectly solve with RTG or solar panels. So if we dont have a nuclear reactor already in space with good kw/kg is because we never neeed them! 4kg/kw magic???? you can reach 2kg/kw with ease. The fact that the ISS still use 1960-1990 technology, is not a conclusion to think we can not improve it, when in fact we already use much better materials and tech in our common life each day.Also 800 mwt?? ok, keep making your numbers. The OP and the paper said 39 days to mars, it does not clarify if is manned or not. In any case, multiply that by 2 and you have your reactor power (depending the radiator you choose) Maybe you dont know what science fiction means, it means that is base on science and physscis laws but nobody builded yet. I already mention and I give details and links on kw/kg for reactors and radiators designs. You can fix the vasimr engine - radiators - reactor - (extras) at 2kw/kg (without payload) Lets said you do it at 3 or 4.. that is still a lot better than any nuclear thermal rocket. Ok, you are complety unable to admit any mistake or misconception. Yesterday you was not able to difference between a normal pump from a heat pump, or the simple fact that PV does not need the same radiators than a nuclear power system. Those things are basic to know how much you understand on thermodynamics. Without even mention all your other misconceptions. Not sure why you try to denied it, I can quote your previous post.. About your "impossible tech": https://en.wikipedia.org/wiki/Magnetohydrodynamic_generator These things are here since a lot of time, they never was use in big scale because there are different and more economic options for similar task in earth, for space they would work much better due microgravity. So you dint laugh I guess. What errors? he is assuming a lot of weight for its reactor that he really does not need to assume. He took a nerva reactor of 350 mw that weights 1750kg, then did an estimation of a aprox 50 mw reactor that weights 3000 kg... Really.. not sure who can laugh about that... And he took those estimations, because that mass is low in comparison with the rest of the system, so it does not matter if the reactor weights less or more. You dont need to consider, is all in the papers. Its around 1 or 2 kw/kg (this include the radiators needed for the engine)You have a graph that show the mass and density depending the power. https://www.ise.fraunhofer.de/de/veroeffentlichungen/konferenzbeitraege/konferenzbeitraege-2014/29th-eupvsec/tibbits_-4cp.2.1.pdf 40% in space, and those are not the last triple juctions made. It will be great for the ISS, it does not need extra radiators, just two very little, this is because it will ignite by short amounts of time, then it cool, then again.

Ah sorry, when I saw 306000 seconds, I was imagine that was C (in km), but C in meters is 300,000,000, there my whole confusion. Also I dint imagine that you have into account the decimals from G. About the power needed, not sure if that calculation is so easy to do, but I dont have much time now to check the math, but well, if that is the case, then we need to calculate the amount of antimatter to keep up with the needs. There is a paper source talking about this? ion-scoop-antimatter?

Ok here it is.. http://www.adastrarocket.com/Andrew-SPESIF-2011.pdf It said 50mw for a 39 day trip, not gigawatts as you said.... you have a word about that? I dint check your math, sorry, but due how wrong was your last answers, I prefer to look in better sources. Also it does not matter if your thrust is low, meanwhile at the end of the month or week, you achieve a lot of speed. Here, learn from these papers about vasimr ships. http://web.mit.edu/mars/Conference_Archives/MarsWeek04_April/Speaker_Documents/VASIMREngine-TimGlover.pdf Take a look, 12 mw, mission to mars, half of time than a nuclear thermal rocket of 1000 mw reactor. But you are wrong, now I understand why you think this way.. By this paper: http://www.adastrarocket.com/NETS2013.pdf That use compressors as heat pumps to increase the thermal difference between the core temperature and the radiator return, they achieve to increase the carnot efficiency this way, but that extra amout of power is wasted to run the compressors. So you reach a similar result if you dont use compressors, but you might thing that if you have a radiator working at 1000 or 1500 C close to the ship, it will heat the rest of the ship? No, because you just need to use a plain base radiator "l" with a reflective surface bloking the crew and the engine. Read the paper. This is also the source of your other mistake, that normal pumps consume a lot of power, but this is not a fluid pump, is a "heat pump" (compressor). Ok, I take a look to the efficiencies, for a 200kw vasimr engine (already tested) you have a 72% of efficiency, and that efficiency increase with the power. So we might be talking of 80 or 85% efficiency for 10 or 20 mw engine. The mass of the vasimir after 10 mw, is 1kw/kg, so 10 tons for 10 mw. But under pressure I imagine.. not sure in vaccum. Also if you dont use compressors, just the doplet radiator, the temperature of return does not change much vs the initial. You are mad? XD Remember that you said that 45% PV efficiency was a lie.. now you know they are very old and are used in all sattelites, but this is your answer? About the weight, there are new PV that use the same technology that are light and kinda flexible. Not sure what you mean by high mass passive radiators.. the same PV act as radiators.. you dont need extra radiators.. so not sure why you mention the word "mass". But I dint hear any self correction from your last post when you claim it that you will need extra radiators at 1600 C to cool the PV Read the papers, vasimr PV are also mentioned. Yeah, they might be less effective far from sun and with big payloads, but they are the best option for low payloads and closer than mars. Go back to the uni. how many other things I need to correct you? Also, there is not shame to said.. sorry I mistake.

Ah, so we are dodging missiles in space now? Are you trolling? ??? Since when you need to land the transfer vehicle? Not matter what kind of propulsion your transfer vehicle use, it always remains in orbit, it will be a waste of proppelent to land it. values as 2kw/kg are for the radiator.. not the reactor. As I said, you may have 100 mw reactors at 100kw/kg or 200kw/kg Or something similar.

I dint made the calculation, if you did or have a source to support your claim please post it. Also I am not talking about 39 days to mars, just a vehicle that can do the trip in half of the time and can be reusable to any trip in our solar system, that will reduce the cost of all future mission. HAHAHAHAHA, so lets make the calculation, imagine you have 50 or 100 mw for the reactor, you need to cool it, you have an idea how much flow you get for X power? One example: for a 0.5 mw pump, you get 1m3 of water by second at 4 bar. You are looking for energy loses in the wrong places. That heat to electrical conversion is the carnot efficiency+ 5% loses in the electrical generator, and yes, you need to radiate the waste heat (that is why we have radiators, and they are responsable of the 80 to 90% of the weight from the whole system without counting payload. So not sure what is your point more than repeat all the things that we already said. No, you are mixing techs, here you need to move matter that carry heat (coolorant), from the core to the radiators, so you just move them with a pump (kinetic energy). But compression and expansion, that is a heat pump!, which is different than a kinetic pump. In that case you are moving heat, not matter or fluids. Heat pumps are usufull when you need to cool stuffs as super conductors, when you need to reach 60k or 3K, a radiator to the space with just little diference between source and destiny, it will have a terrible efficiency. So you move forcing that heat with a heat pump, this consume power (much more than a simple electrical pump, but it does not matter because they are two very different things.) Lithium has low heat capacity, I read in some place that ferrofluids or other different kind of metal liquids are more promising. But well does not matter. About the radiator and heat pump for the superconductors and engine, if they work with superconductors then not sure how they have 40% of energy loses... When most of all kind of electrical work are very efficient. They plan to use it as first application, to keep the space station in orbit. So if that works fine, then they will use it for any other application they want. a mars mission is not discarded, more taking into account that this was their main excuse to not go to mars in all these years.. First the liquid lithium is your idea, nobody mentioned that before.. is just come from your head. About solar panels, all new solar panels that goes to space has 45% efficiency. http://sunmetrix.com/wp-content/uploads/2014/09/NREL_efficiency_chart.jpg Also saying that I need to keep them at 1600k shows that you dont have much idea what are you talking about. One thing is a heat engine which needs to move that heat to a radiator (where the difference of heat between the heat engine and the radiator is what matters), and another very different thing is a normal PV in the sun, when it will be able to radiate that temperature just working at 30 Celcius degree already is enoght to radiate those 65% extra. You dont need pumps or extra radiators. is just as any other PV in space. Because clearly you still need to learn more about the subject.You have some mixing concepts. But dont blame the technology. Once you understand it, you will start to love it.

Is not better!! a nuclear thermal rocket only has 1000 ISP, it may have 2000 secs as maximun with complex designs. Vasimr has from 5000 to 50000 seconds, so even if you need to use a huge radiator, it worth it. There are a lot of radiators paper that I already post, that reach 1kw/kg or 2kw/kg. Also vasimr does not require any specific radiator mass, if is lower, it will work better and it will be cheaper. Magic reactor? a reactor is a reactor.. You have nuclear submarines or any other kind of artifact using big or small reactors. Where is the magic?? Depending the amount of fission material that you have plus the moderator substance + control rods (that act as a brake) it will determine the amount of heat you release. That´s all. Then you need to choose how to cool it, in a rocket you may use the same proppelent, if you want to use the heat to produce electricity, then you will use a pump or other methods inside the reactor to move that heat in a close cycle to a heat exchanger that will be connected to the cycle fluid from your radiator. This is space, so you have a lot of tricks that you can use as magnetic confining to reduce the mass of the reactor or rise its working temperature. So instead release that heat with the proppelent, you connect it to a heat exchanger in a close cycle. That is the only difference.. But you dont need to include the radiator mass in the reactor mass. So? This is like said that is not possible to eat in space because spoons dont work there. Any time that you have a different task, the nuclear reactor will be specific designed to that task, if you use critic co2 or helium or water as main working fluid, what kind of fission material or mix you use, if it needs control rods or not, all that is designed for each reactor.. Is like design a new ICE engine depending the car or truck it will use it, you dont need to shoot you in your head to avoid that. Is not magic.. it almost happen in each new car model we see.

I just use that study to know how much it will weight a reactor.. A reactor is a reactor.. how is cool it may be different, for vasimr we need huge radiators, but for rocket you use the same proppelent. The only difference will be with a molten salt rocket, that is different.

Try to read, is the only that I am asking you.. In the link is all explained. Reactor power (at electric power mode) 100 MWth (100 kWth) Avg. fuel power density 14.7 MWth/L Number of fuel elements 37 Pitch to diameter ratio 2 Fuel type, U enrichment, and mass (235U mass) (U, Zr, Nb)C, 93 wt%235U/U, & 40∼50 kg (4 kg for 7LiH & 9 kg for ZrH1.8) Moderator type and mass 13 kg for 7LiH 93 kg for ZrH1.8 Reflector (PV) type and mass (including control drums) Be – Be – C/C & 97 kg Total reactor mass 180 kg for 7LiH 268 kg for ZrH1.8 Reactor diameter and height (core diameter and height) 50 & 46 cm (39.2 & 39.2 cm) The true reactor thermal power output is 100 megawatts!! It does not matter much if this reactor is used as rocket and the colling system is the same proppelent, because I am not saying that the reactor + cooling system will weight just that, I am saying that the reactor will weight that. When it said 100kw electric, is because that rocket design will also need electricity, so it has an auxiliar generator that only uses 100kw. But the reactor power is 100 MW. First, we dont need 100 Mw, maybe with just 50Mw is enoght for a manned mission, lets imagine that it will weight a bit more for X reasons.. 50 Mw - 1 Ton, this still is nothing compare to the mass you need for the radiators. So the reactor is very light (ask to anyone), the main issue here is the radiator mass.

Ok you are right.. I forget about the pitch. I am not sure either about the exact energy setup, I know that it will use gasoline and the motors are measure in cc, so I imagine that all motors are ICE. But not sure how they plan to control the thrust if is like that, a pitch mechanism may work, but not sure if they have space for that. ICE + Pitch sound like it needs a lot of weight and space. Hybrid engine may work, but we also have a weight concern. But if they are smart enoght, I guess is possible to find a good solutions to the safety, range and energy source. In the first page I show the details of the first prototype, they will change it for 4 engines for the second, not sure what other changes will have. You can see it in their page too. http://www.hover-bike.com/MA/the-hoverbike/how-you-can-own-it/ --------------EDIT------------------ Forget what I said, almost all our answers are explained in the FAQ section.

The second idea to put the bowl in water, only works fine if the bowl is metal.. remember that.

But even space applications focus in cost. If you need millions of those perfect printed or placed layers, the cost will rise so much, that it will be even pointless for space. It can be usefull in the future with new manufacture techniques, they can make aerogel base on graphene oxide or graphene ink, which are 3d materials that are produced as a whole.. no stacking layers after layer.

See the link that I provide SargerRho

Its mentioned here: http://www.sciencedirect.com/science/article/pii/S1738573315001540 Search for "reactor total mass". But those liquid doplet radiators does not use water! XD They use metals which remains liquid at very high temperature and in vaccum.

That might work if you want micro batteries with micro capacity. But if you want to enter to the 3d world where objects had more than 1 cm of thick, then your battery will skyrocket in cost, something that might be really pointless not matter its niche.

Ok, there are a lot of pointless high tech answers.. Peadar has a good one, I use it each morning with my Tea, half of hot water, then once the tea is dissolve, I add cold water. But if your soup is not instant soup, you need to use a different trick. 1- Use a metal bowl, not ceramic or plastic which are good insulators. 2- Put the bowl on water. Another old trick is to have two bowl or containers, you drop the soup to one bowl, then from that bowl to the first, you repeat that process 5 or 7 times, and your soup is already cold.