19 3 (2009 9 ) J Korean Soc Occup Environ Hyg 2009;19(3):240~249 Numerical Study on Ventilation Method for Temperature Control of HRSG Building Chul Hwan Kim Jong Wook Lee Hoon Ki Choi Geun Jong Yoo Dept. of Mechanical Design and Manufacturing Engineering, Changwon National University HRSG(Heat Recovery Steam Generator) building is large enclosed structure included various heat sources. This building needs to appropriately keep internal air temperature for worker's safety and operability of control devices. In this study, ventilation analysis is performed to find proper ventilation method for temperature control. Ventilation analysis is applied to entire internal space of the building with standard k- model and enhanced wall treatment because of large size of the structure. And the ventilation method is considered natural and forced convection with two louver structures which has damper or not. Louver structure affect directly air circulation in near HRSG and lower region of the building. Forced ventilation provides strong inertial force which cause upward airflow. From the analysis, it is found that design requirement for internal air temperature can be satisfied by forced ventilation method with louver structure without damper. Key Words : ventilation, HRSG building, numerical analysis, k- model, louver structure HRSG. HRSG. HRSG. HRSG. HRSG HRSG. HRSG HRSG,. HRSG.,, : 2009 5 28, : 2009 9 11 : ( 641-773, Tel : 055-286-7576, E-mail : churani@changwon.ac.kr)
241. Chen,, RANS (Chen, 1995) Reynolds (Chen, 1996), LES (Zhang & Chen, 2000). Stavrakakis (2008) RANS. Low-Reynolds.. Blay (1992) LRN(Low-Reynolds number) k-. Yilmaz Fraser(2007) LRN k-.,.., (Kang et al., 2008),.. Kim et al. (2005, 2008).. Kim et al.(2005, 2008) HRSG. (Betts Bokhari, 2000) HRSG. HRSG. HRSG HRSG. HRSG 50 Ra(Rayleigh number) 10 13. Ra 10 9,. HRSG. (1) Navier-Stokes (2), (3)., Reynolds ( ). k- (Launder & Spalding, 1974)...., (2) ( ).,. Boussinesq, (4) ( ) ( ),.
242.. HRSG. Twolayer (Jongen, 1992) Kader (1981) Enhanced wall treatment (Fluent Inc., 2006).. Fluent v6.3.26. (2) SIMPLE. 1, (Patankar, 1980) PRESTO (Fluent Inc., 2006). HRSG. 5 10-6, 10-3. HRSG Fig. 1 36.2m, 112.7m, 39.15m. 3 HRSG,. HRSG, 27.8m, 7.7m. HRSG I (Girder) HRSG. HRSG 3. Fig. 2,. HRSG Fig. 3.
243, Fig. 4.,.. (c),., HRSG. HRSG... HRSG,, HRSG. Cases No. of Grid (million) Ventilation method Louver structure total (kg/s) Tm ( ) Tw,avg ( ) hw (w/m2 ) 1 750 Natural (A) 155.21 46.43 50.43 5.67 2 630 Natural (A) 155.23 46.44 50.41 5.67 3 485 Natural (A) 155.26 46.44 50.42 5.67 4 492 Natural (B) 155.82 46.29 50.18 5.56 5 441 Natural (A) 321.89 41.47 46.15 6.50
244 490, 630 750 HRSG,,. Table 1, (Case 1~3) 0.1%. 485 (Case 3) 440 ~490. HRSG. Table 2. HRSG (Heat gain) (Heat flux).. (Ventilator) -Table 2 (-) -,. Fig. 5 Components Lower louvers (Natural) Upper louvers (Forced) Ventilator Pressure outlet: Atmosphere; Temperature: 37.2 Pressure outlet: Atmosphere; Temperature: 37.2 Velocity: -19.62m/s Boundary Conditions Heat sources etc. structures Walls HRSG, Drums Pumps Heat flux: 285.76 W/m2 (Heat gain: 2074 kw, Area: 7257.9 m2) Heat flux: 1690.07 W/m2 (Heat gain: 300kW, Area: 177.5 m2) Adiabatic No-slip
245 6 37.2. 50. HRSG.,. HRSG Betts Bokhari(2000). Betts Bokhari(2000) Fig. 6 2.18m, 0.76m, 0.52m. 54.7 15.6.. Ra=1.43 10 6 (Betts Bokhari, 2000). Fig. 7..,... HRSG. HRSG.. Fig. 8 HRSG. 10m. 10m.. HRSG.. HRSG. HRSG.,,. Fig. 8
246 (c). Fr(Froude number), (5)(Blay et al., 1992). Fig. 9 Fr. Fr 2.5
247 1.., HRSG Fr 0.5. Fig. 10 50. z=15m 41. HRSG. z=30m 50., HRSG. Table 1 2.1. Fig. 11 HRSG HRSG HRSG. HRSG HRSG
248. HRSG Fig. 12 Fr 1. Fig. 11 HRSG HRSG. Fig. 11(c)., 48 Fig. 13.. Table 1 HRSG 4 HRSG 1 w/m2. HRSG.., HRSG,., HRSG. HRSG,. HRSG. HRSG,. (c) 2009.
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