How does a BWR reactor work?
Boiling Water Reactors BWRs heat water and produce steam directly inside the reactor vessel. Water is pumped up through the reactor core and heated by fission. Pipes then feed the steam directly to a turbine to produce electricity. The unused steam is then condensed back to water and reused in the heating process.
What is the typical pressure in BWR?
In the BWR, the water in the reactor core is permitted to boil under a pressure of 75 atm, raising the boiling point to 285°C and the steam generated is taken from the core and used directly to drive a steam turbine.
What is the typical pressure MPa in a BWR?
As boiling of the reactor coolant occurs at the upper region of the core coolant channels, a water-steam mixture exits the reactor core (into the upper plenum) at saturation temperature. Nominal core operating pressure is typically 7.0 MPa, which is nearly the same for all BWR designs.
Which is safer BWR or PWR?
Since the fluid is maintained at high pressure, so the PWR core volume is less. For the same power generation, core volume of the BWR is comparatively larger. Since the working fluid loop is separated from the primary loop, so PWR is less risky in spreading of radioactive materials owing to leakage.
Which is safer PWR or BWR?
Since the working fluid loop is separated from the primary loop, so PWR is less risky in spreading of radioactive materials owing to leakage. Since same fluid passes through the reactor and turbine in BWR plants, so any leakage in the turbine can spread radioactive elements into the atmosphere.
How many fuel assemblies are in a BWR?
370-800 fuel assemblies
BWRs contain between 370-800 fuel assemblies.
Where is boiling allowed in PWR?
In comparison, there is no significant boiling allowed in a pressurized water reactor (PWR) because of the high pressure maintained in its primary loop—approximately 158 atm (16 MPa, 2300 psi).
What is the main difference between BWR and PWR?
So the basic difference in BWR and PWR lies in the fact that while steam is produced in a pressure vessel in BWR, hot water passes into a steam generator in the case of a PWR. More than 70% of the nuclear power generators that use light water are PWR in US.
How does a jet pump BWR work?
Typical jet pump BWR steam supply system. Normal operation of a BWR depends upon accurate prediction of several key thermal hydraulic parameters in the fuel assemblies. In particular, vapor void fractions, transition boiling limits and fuel assembly pressure drops must be accurately predicted to support BWR design and operation.
How is reactor pressure controlled in a BWR plant?
All BWR plants have safety relief valves (SRVs) to -provide overpressure protection, and hence control reactor pressure. -Some BWR facilities have “-systems which can control .pressure without requiring the use of the SRVs.
What is the function of circulating water in a BWR?
In a BWR, the circulating water serves both as cooling medium and neutronic moderator for the nuclear fuel. This produces close coupling between power generation and two-phase flow conditions in the fuel assemblies.
What is the difference between BWR 1 and BWR 2?
The BWR/1 was the first BWR design with internal steam separation. It also had an isolation condenser, and pressure suppression containment. BWR Type 2 (BWR-2, BWR/2): Introduced in 1963, >500 MW e, typically around 650 MW e gross ( Oyster Creek, Nine Mile Point 1 ).