SPACE TECHNOLOGY
Nuclear Thermal Rockets
NASA is about to fund renewed research and experimentation into NTRs. Public approval will be hard
With the capability of generating high thrust and 100% more specific impulse than the best chemical rockets, the time and cost-saving potential of nuclear thermal rockets (NTR) for deep-space missions is once again gaining interest at NASA. Although never flown, the NTR concept is relatively simple. The rocket engine is based around a nuclear fission reactor, which heats the liquid hydrogen (LH2) propellant instead of igniting combustible fuel.
https://archive.is/wzK3R
The resulting hot gas is pumped into a separate high-pressure chamber, which, through valve 11 communicates with tube shocks. At the other end of the shock tube we find structed diffuser serves to concentrate the energy of the shock wave, and the valve 12, connecting tube with a nozzle rocket.
Duty cycle engine is as follows: pump 5 takes the working fluid from the reservoir and high-pressure pumps it through a reactor, where it evaporates and is heated to about 2500° C — and then injected into the high-pressure chamber. Shock tube at this point is still filled with gas of low pressure left over from the previous cycle. Then the valve 11 to quickly open, compressed gas, bursting into the pipe instantaneously compresses and heats the gas in the tube, causing the appearance in it of a strong shock wave.
https://archive.is/ReYxU
A proposed space elevator stretching 12 miles into the stratosphere could cut out the need for rockets to shuttle astronauts into space, according to a proposal from a Canadian company.
It sounds like an idea out of a science fiction novel, but Thoth Technology has been granted a patent for an inflatable, pneumatically pressured tower stretching 12.5 miles high. The top of the so-called space elevator would serve as a liftoff point to space, potentially saving more than 30 percent of the fuel of a conventional rocket, according to the company.
"From the top of the tower, space planes will launch in a single stage to orbit, returning to the top of the tower for refueling and reflight," Brendan Quine, the inventor of the ThothX Tower, said in a statement.
By removing the need for the vertical launch of a rocket, energy can be saved, allowing space passengers to catch a horizontal flight, much like a passenger plane, from the top of the space elevator.
Aside from being a final stop for astronauts before heading out of this world, Quine wrote in a filing with the United States Patent Office that the tower could help with wind-energy generation, communications, scientific research and tourism.
While it's just an idea for now, the patent moves it one step closer to potentially being another way to revolutionize space travel.
https://archive.is/R2rqr
A potential advancement in the United States’ electric propulsion capability for the future of spaceflight is being underscored by a new NASA contract to support work on the VASIMR project – short for the Variable Specific Impulse Magnetoplasma Rocket.
VASIMR works with plasma, an electrically charged gas that can be heated to extreme temperatures by radio waves and controlled and guided by strong magnetic fields.
Ad Astra Rocket Company announced today that it has completed contract negotiations with NASA on the group’s Next Space Technology Exploration Partnerships (NextSTEP) award and are now entering the execution phase of the project.
Long duration, high-power test
Under the award, Ad Astra is to conduct a long duration, high-power test of an upgraded version of the VX-200™ VASIMR prototype, the VX-200SS (“SS” for steady state), for a minimum of 100 hours continuously at a power level of 100 Kilowatts.
Testing will be conducted in Ad Astra’s large, state-of-the-art vacuum chamber in the company’s Webster, Texas facility.
The NASA and Ad Astra executed the contract — a three-year, fixed price agreement — on August 7, 2015 for a total value of just over $9 million.
The agreement is structured as a one-year contract with two additional one-year extensions based on the accomplishment of mutually agreed upon progress milestones, Ad Astra added in their press statement.
NASA’s Advanced Exploration Systems Program sponsors NextSTEP awards in a 50/50 cost partnership with industry.
Former astronaut, Franklin Chang Díaz, serves as Chairman of the Ad Astra Board and Chief Executive Officer – a space traveler with NASA for 25 years and a veteran of seven space shuttle flights.
https://archive.is/S46q8