Rankine cycle system

Abstract

A Rankine cycle system includes: a superheater, an expander including a first outlet discharging steam and a second outlet discharging liquid refrigerant produced therein; a first discharge path discharging the steam from the expander; a condenser condensing the steam introduced through the first discharge path into liquid refrigerant, a condensed water tank reserving the liquid refrigerant produced in the condenser; and a second discharge path discharging the liquid refrigerant from the expander to the condensed water tank, wherein a liquid level in the condensed water tank satisfies a following relation: Δh>ΔPto/ρg, when Δh means a height difference between the liquid level and a lowest liquid level in the second discharge path, ΔPto means a pressure loss when the steam flows into the condenser from the expander through the first discharge path, ρ means a density of the liquid refrigerant, and g means a gravitational acceleration.

1 . A Rankine cycle system comprising:
 a superheater,   an expander that is driven by steam, which is vaporized refrigerant supplied from the superheater, to recover energy, and includes a first outlet discharging steam and a second outlet discharging liquid refrigerant produced by condensation of the steam in the expander;   a first discharge path that is connected to the first outlet and discharges the steam from the expander;   a condenser into which the steam is introduced through the first discharge path, and that condenses the steam into liquid refrigerant,   a condensed water tank that reserves the liquid refrigerant produced in the condenser; and   a second discharge path that connects the second outlet to the condensed water tank and discharges the liquid refrigerant from the expander, wherein   a liquid level in the condensed water tank satisfies a following relation:
   Δ h>ΔPto/ρg,  
 
   when a height difference between the liquid level and a lowest liquid level in the second discharge path is expressed by Δh, a pressure loss when the steam flows into the condenser from the expander through the first discharge path is expressed by ΔPto, a density of the liquid refrigerant is expressed by ρ, and a gravitational acceleration is expressed by g.   
     
     
         2 . The Rankine cycle system according to  claim 1 , wherein
 the second outlet is provided to a downside portion of the expander.   
     
     
         3 . (canceled) 
     
     
         4 . The Rankine cycle system according to  claim 1 , wherein
 a connected position of the second discharge path to the condensed water tank is located higher than the lowest liquid level in the second discharge path.   
     
     
         5 . The Rankine cycle system according to  claim 1 , wherein
 a diameter of the second outlet is smaller than a diameter of the first outlet.   
     
     
         6 . The Rankine cycle system according to  claim 1 , wherein
 a flow passage area of the second discharge path is smaller than a flow passage area of the first discharge path.