Propulsion Using Nuclear Energy
Construction and Working Explained
This article discusses another application of nuclear energy - Propulsion. Construction and working of the mechanism are discussed in brief.
Apart from power generation, nuclear energy is now being used in many other ways, propulsion being one of them. The growing concerns about vehicular emissions and rising prices of crude oil have made mankind look for more efficient and pollution-free methods to obtain energy for propulsion. Though the nuclear propulsion method can’t be used for smaller vehicles yet, it’s being used for major modes of transportation like large surface ships and submarines.
Power Generation Process In Brief
The energy used for propulsion is generated by a nuclear reactor present aboard the ship or submarine. The nuclear fission reaction which takes place in the reactor produces heat to convert water into steam, which is used to turn turbines that power the onboard systems and drive the propeller.
Construction Of The Onboard Nuclear Reactor
The reactor used in this process is a pressurized water reactor (PWR). The reactor is surrounded by multiple layers of shielding materials to protect the crew members from the radiation.
There are 2 systems present within the reactor unit:
- The primary system circulates water at high pressure between the reactor and the heat exchanger. The high pressure of the water prevents it from boiling.
- The secondary system circulates steam which is used to turn the turbines and produce energy. The fluids flowing through these systems don’t mix with each other.
The components used in the construction and operation of these reactors are required to be of exceptionally high quality, as a minor flaw could lead to destruction of the entire vessel and loss of lives. The reactor is usually placed in a separate reactor compartment which grants access to operators and crew for maintenance and repair purposes.
Benefits Of Using Nuclear Power For Propulsion
a) Nuclear power provides freedom from exhaust emissions. Use of the cleaner nuclear energy eliminates this problem completely.
b) Nuclear fuel gives greater quantity of energy per unit quantity of fuel. Excessive quantities of fuel are not required, especially in a time when crude oil resources are depleting fast.
c) It doesn’t require air or oxygen for combustion, which means it’s perfect for submarines which operate under water for long periods of time at a stretch.
All necessary precautions are taken to prevent the nuclear fission reaction from becoming a chain reaction. The uranium fuel used in these reactors is specially designed with a layer of metal cladding surrounding it to make it safer and hence is resistant to corrosion and radiation. The products produced in the fission reaction are stopped in the cladding and their kinetic energy is converted to heat.
