NASA plans to send manned missions to Mars in the following decade – however the 140 million miles (225 million kilometers) journey to the Red Planet The round trip can take several months to years.
This relatively long duration is on account of using conventional chemical rocket fuel. An alternative technology to the chemically powered rockets the agency is currently developing is known as nuclear thermal propulsion, which uses nuclear fission and will One day power a rocket This means the journey only takes half the time.
Nuclear fission utilizes the incredible amount of energy released when an atom is split by a neutron. The The response is known as a cleavage response. Fission technology is well established in power generation and nuclear-powered submarines, and its application to power or propel a rocket could sooner or later give NASA a faster and more powerful alternative to chemically powered rockets.
NASA and the Defense Advanced Research Projects Agency are joint development of NTP technology. They plan to deploy a prototype system into space and reveal its capabilities in 2027 – potentially making it one in all the primary of its kind to be built and operated by the US
Nuclear thermal propulsion could also sooner or later provide energy maneuverable space platforms that may protect American satellites out and in of Earth orbit. But the technology remains to be developing.
I’m a Associate Professor of Nuclear Engineering on the Georgia Institute of Technology whose Research group creates models and simulations to enhance and optimize designs for nuclear thermal propulsion systems. My hope and fervour is to assist develop the nuclear thermal propulsion engine that can enable a manned mission to Mars.
Nuclear versus chemical propulsion
Traditional chemical propulsion systems use a chemical response involving a lightweight fuel akin to hydrogen and an oxidizer. When these two mix together, they ignite, causing the fuel to come back out of the nozzle in a short time and power the rocket.
NASA Glenn Research Center
These systems don’t require an ignition system and are due to this fact reliable. However, these rockets need to move oxygen into space, which might put a strain on them. Unlike chemical propulsion systems, nuclear thermal propulsion systems depend on nuclear fission reactions to heat the fuel, which is then ejected from the nozzle to supply the propulsion force or thrust.
In many fission reactions, researchers send a neutron toward a lighter uranium isotopeUranium-235. The uranium absorbs the neutron and uranium-236 is created. The uranium-236 then breaks down into two fragments – the fission products – and various particles are released throughout the response.
More than 400 nuclear reactors in use worldwide currently use nuclear fission technology. Most of those nuclear reactors are in operation Light water reactors. These nuclear fission reactors use water to decelerate the neutrons and absorb and transfer heat. The water can produce steam directly within the core or in a steam generator that drives a turbine to generate electricity.
Nuclear thermal propulsion systems work in the same way, but use a distinct nuclear fuel that accommodates more uranium-235. They also work at significantly higher temperatures, which makes them extremely powerful and compact. Nuclear thermal propulsion systems have an influence density around ten times higher than a traditional light water reactor.
Nuclear propulsion could possibly be a step ahead of chemical propulsion just a few reasons.
A nuclear engine would eject and produce fuel in a short time from the engine's nozzle high thrust. This high thrust allows the rocket to speed up faster.
These systems even have a high specific impulse. Specific impulse measures how efficiently the fuel is used to generate thrust. Nuclear thermal propulsion systems have about twice the precise impulse as chemical rockets, meaning they may reduce travel time by an element of two.
History of Nuclear Thermal Propulsion
For many years, the U.S. government has funded the event of nuclear thermal propulsion technology. Between 1955 and 1973 programs were at NASA, General Electric And Argonne National Laboratories produced and tested 20 nuclear thermal propulsion engines.
But these pre-1973 designs relied on highly enriched uranium as fuel. For this reason, this fuel is not any longer used Dangers of proliferationor threats related to the proliferation of nuclear materials and technology.
The Global Threat Reduction Initiativelaunched by the Ministry of Energy and National Nuclear Safety Authoritygoals to convert most of the research reactors that use highly enriched uranium fuel to high sample low enriched uranium fuel (HALEU).
Compared to highly enriched uranium fuel, highly enriched, low enriched uranium fuel accommodates less material that may undergo a fission response. So the rockets need to be loaded with more HALEU fuel, which makes the engine heavier. To solve this problem, researchers are searching for special materials that might use the fuel in these reactors more efficiently.
NASA and the DARPAs Demonstration rocket for agile cislunar operationsThe program (DRACO) intends to make use of this low enriched, high content uranium fuel in its nuclear thermal propulsion engine. The program plans to launch its rocket in 2027.
As a part of the DRACO program, aerospace company Lockheed Martin has partnered with BWX Technologies Development of reactor and fuel designs.
The nuclear thermal propulsion engines under development by these groups must meet certain performance and safety standards. You need a core that’s operational in the course of the mission and might perform the essential maneuvers for a quick journey to Mars.
Ideally, the engine should have the ability to generate high specific impulse while meeting the necessities of high thrust and low engine mass.
Ongoing research
Before engineers can design an engine that meets all of those standards, they need to start with models and simulations. These models help researchers like those in my group understand how the engine would handle starting and shutting down. These are processes that require rapid, massive changes in temperature and pressure.
The nuclear thermal propulsion engine shall be different from any existing nuclear fission energy system, so engineers might want to develop software tools that work with this latest engine.
My group Designs and analyses Reactors with thermal nuclear propulsion based on models. We model these complex reactor systems to see how things like temperature changes can affect the reactor and the security of the rocket. However, simulating these effects can require a number of expensive computing power.
We worked on it develop latest computing tools This model shows how these reactors behave while they’re in operation Commissioning and operation without using up a lot computing power.
My colleagues and I hope that this research can sooner or later help develop models that might control the rocket autonomously.
image credit : theconversation.com