Autumn Sun ☀️ on Nostr: I can't put down the thoughts of how much the Chernobyl plant operators fucked up... ...
I can't put down the thoughts of how much the Chernobyl plant operators fucked up... I mean, apart from that they managed to turn their Reactor Number Four into a low-yield nuclear bomb.
I've spent a few days reading up on reactor and fission mechanics and the RBMK reactor design and it's unbelievable how much the operators of the plant f'd up during the test on the nught of the 26th of April, 1986...
They were supposed to test if the electrical output from the main steam turbines of the reactor 4 itself was sufficient to deliver electrical power to the main coolant pumps for the duration of the ~60 seconds it takes for the emergency diesel generators to reach full power.
Keep in mind that it's not just like a natgas furnace that requires a bit of cooling here. The RBMK-1000 reactor design was a large reactor with a design thermak output of 3200 megawatts. For comparison, a typical household wood-burning stove or fireplace delivers 1000-4000 watts of thermal energy, so the heat output of the reactor is about that of a thousand stoves burning at full blast.
Then consider that the chain reactions in the RBMK-1000 tales place in an enclosed space: A steel cylinder 11 metres across and 7 metres from bottom to top; this is a tremendous heat energy density that this reactor is handling and containing in its normal operation!
This leads to the cooling needed; the reactor needs much more than your typical household circulation pump, one such would usually deliver a few cubic metres of water to heat your home.
Enter Reactor 4 at Chernobyl: The coolant pumps were designed to deliver several cubic metres of water PER SECOND, EACH. The reactor has water circulation split into two separate circuits, each serviced by four pumps where three are normally running, with one cold spare in case of breakdown or maintenance.
Hence why even massive, industrial diesel generators would need a minute to reach necessary speed to power the pumps; it would require somewhere around 50 Megawatts of electrical power to supply the coolant pumps. (A Honda gasoline generator the size of a doghouse can deliver around 8 kilowatts, for comparison). That's how much water was necessary to sufficiently cool a running RBMK reactor.
Only on this night, all four pumps in both circuits were running at full capacity (the test only touched on one of the two circuits) deviating from normal operating circumstances. One, in that the extra running pump would impose additional drain on the main steam turbines at they were coasting to a halt. And second and more importantly, that the high coolant flow was allowing very little steam to be generated in the reactor, further exacerbating the test circumstances by lowering electrical generation....
To be continued...
#nuclear #tech #history
I've spent a few days reading up on reactor and fission mechanics and the RBMK reactor design and it's unbelievable how much the operators of the plant f'd up during the test on the nught of the 26th of April, 1986...
They were supposed to test if the electrical output from the main steam turbines of the reactor 4 itself was sufficient to deliver electrical power to the main coolant pumps for the duration of the ~60 seconds it takes for the emergency diesel generators to reach full power.
Keep in mind that it's not just like a natgas furnace that requires a bit of cooling here. The RBMK-1000 reactor design was a large reactor with a design thermak output of 3200 megawatts. For comparison, a typical household wood-burning stove or fireplace delivers 1000-4000 watts of thermal energy, so the heat output of the reactor is about that of a thousand stoves burning at full blast.
Then consider that the chain reactions in the RBMK-1000 tales place in an enclosed space: A steel cylinder 11 metres across and 7 metres from bottom to top; this is a tremendous heat energy density that this reactor is handling and containing in its normal operation!
This leads to the cooling needed; the reactor needs much more than your typical household circulation pump, one such would usually deliver a few cubic metres of water to heat your home.
Enter Reactor 4 at Chernobyl: The coolant pumps were designed to deliver several cubic metres of water PER SECOND, EACH. The reactor has water circulation split into two separate circuits, each serviced by four pumps where three are normally running, with one cold spare in case of breakdown or maintenance.
Hence why even massive, industrial diesel generators would need a minute to reach necessary speed to power the pumps; it would require somewhere around 50 Megawatts of electrical power to supply the coolant pumps. (A Honda gasoline generator the size of a doghouse can deliver around 8 kilowatts, for comparison). That's how much water was necessary to sufficiently cool a running RBMK reactor.
Only on this night, all four pumps in both circuits were running at full capacity (the test only touched on one of the two circuits) deviating from normal operating circumstances. One, in that the extra running pump would impose additional drain on the main steam turbines at they were coasting to a halt. And second and more importantly, that the high coolant flow was allowing very little steam to be generated in the reactor, further exacerbating the test circumstances by lowering electrical generation....
To be continued...
#nuclear #tech #history