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B. Yang
efficiency of nuclear power system. The red curve represents the schematic diagram of
the Rankine cycle. The expression of thermal efficiency is:
η t =
(h 3 − h 4 ) − (h 2 − h 1 )
(h 3 − h 2 )
(1)
It can be seen that the key operating parameters affecting the thermal efficiency
of the two-loop system are the pressure difference between the steam generator and
the condenser, while the operating conditions of the two-loop are indirectly limited by
the first-loop operating parameters because of the heat transfer efficiency of the steam
generator. In addition, the influence of power consumption of seawater pump on total
efficiency should be considered [3].
2.1 Simple Rankine Cycle System
Firstly, the influence of the performance parameters on the thermal efficiency of the
simple Rankine cycle model is studied after normalizing the flow rate of the second
loop without considering the space limitation of the system and the mature ability of
the equipment to high temperature and high pressure. The key operating parameters and
equipment efficiency of the modeling are shown in Table 1.
Table 1. Key operating parameters and equipment efficiency of simple rankine cycle
Parameter
Design value
Range of
parameters
SG pressure/Mpa P h
3
2.5–3.5
Condensate
pressure/Mpa
P l
0.016
0.01–0.03
Steam Efficiency η t
0.85
0.7–1
Pump Efficiency η p
1
0.7–1
Superheat
α
1
1–1.2
2.2 Rankine Cycle Preheating System
The engineering operation experience shows that the heat efficiency of nuclear power
unit can be improved effectively by using steam separation reheater, regenerative heater,
condenser performance and regenerative heat exchanger. According to the design of the
secondary circuit of a marine nuclear power system, the equipment such as preheater,
temperature reducing and decompression device, water storage tank, different types of
water pump are added to the original simple Rankine cycle system, which makes the
working fluid and partial extraction of the outlet of the generating steam turbine and the
outlet of the spiral slurry steam turbine mixed and heated [4] in advance in the preheater.
B. Yang
efficiency of nuclear power system. The red curve represents the schematic diagram of
the Rankine cycle. The expression of thermal efficiency is:
η t =
(h 3 − h 4 ) − (h 2 − h 1 )
(h 3 − h 2 )
(1)
It can be seen that the key operating parameters affecting the thermal efficiency
of the two-loop system are the pressure difference between the steam generator and
the condenser, while the operating conditions of the two-loop are indirectly limited by
the first-loop operating parameters because of the heat transfer efficiency of the steam
generator. In addition, the influence of power consumption of seawater pump on total
efficiency should be considered [3].
2.1 Simple Rankine Cycle System
Firstly, the influence of the performance parameters on the thermal efficiency of the
simple Rankine cycle model is studied after normalizing the flow rate of the second
loop without considering the space limitation of the system and the mature ability of
the equipment to high temperature and high pressure. The key operating parameters and
equipment efficiency of the modeling are shown in Table 1.
Table 1. Key operating parameters and equipment efficiency of simple rankine cycle
Parameter
Design value
Range of
parameters
SG pressure/Mpa P h
3
2.5–3.5
Condensate
pressure/Mpa
P l
0.016
0.01–0.03
Steam Efficiency η t
0.85
0.7–1
Pump Efficiency η p
1
0.7–1
Superheat
α
1
1–1.2
2.2 Rankine Cycle Preheating System
The engineering operation experience shows that the heat efficiency of nuclear power
unit can be improved effectively by using steam separation reheater, regenerative heater,
condenser performance and regenerative heat exchanger. According to the design of the
secondary circuit of a marine nuclear power system, the equipment such as preheater,
temperature reducing and decompression device, water storage tank, different types of
water pump are added to the original simple Rankine cycle system, which makes the
working fluid and partial extraction of the outlet of the generating steam turbine and the
outlet of the spiral slurry steam turbine mixed and heated [4] in advance in the preheater.