To overcome the condition that the lowly efficient use of hot air heating in greenhouse, a design method of hot air heating for a porous pipe in greenhouse was put forward. The model of a porous pipe was created by using the Pro/E, the computational fluid dynamics software Fluent 6.2 was adopted to simulate the porous pipe interior flow mechanism and performance by setting up the Reynolds averaged Navier-Stokes equations, the RNG k-εturbulent model and the SIMPLEC algorithm. By using the search principle of bisection algorithms, numeric heat transfer theory, hydrodynamics and back step method, a design method of hot air heating in a porous pipe was studied, meanwhile which was computed by making use of VB 6.0 computer language program. The results show that the flow index of emitter on the porous pipe is 0.507, the performance is fine. When the inlet pressure is 10 kPa, the outlet pressure is 0 Pa, the inlet temperature is 300 K, the outlet temperature is 278 K, the coefficient of conducting heat of the boundary is 0.055, the temperatures on the other orifice on the porous pipe were almost the same, and the pressures had the pressure-drop of about 200 Pa. The results of design were a little higher than that of numerical simulated ones, but the curves agreed with the pressure and temperature. Both the pressure and temperature uniformity coefficients were larger than 0.8, which satisfied the need of hot air flow uniformity for a porous pipe.
WANG Xin-Kun,XU Wen-Bo, Zhao- Kun et al. Numerical simulation and design method of hot air for porous pipe based on CFD[J]. Journal of Drainage and Irrigation Machinery Engin, 2011, 29(1): 82-86.
Xie Shouyoug,Li Xiwen,Yang Shuzi,et al.Algorithm of heating temperature for Chongqing's winter greenhouses[J].Journal of Chongqing University:English Edition,2007,6(l):50-54.
Burt C M.Selection of Irrigation Methods for Agriculture[M].US:ASCE,2000.
Wu I P.Energy gradient line approach for direct hydraulic calculation in drip irrigation design[J].Irrigation Science,1992,13 (1):21-29.
洪明,李援农,邵莉芳,等.低压PE滴灌毛管水头损失试验[J].干旱地区农业研究,2007,25(3):232-235.Hong Ming,Li Yuannong,Shao Lifang,et al.Experimental analysis of head lasses in PE laterals under low pressure trickle irrigation[J].Agricultural Research in the Arid Areas,2007,25(3):232-235.(in Chinese)
Kang Yaohu,Yuan Baozhong,Nishiyama S.Design of microirrigation laterals at minimum cost[J].Irrigation Science,1998,18(3):125-133.
Barragan J,Wu I P.Simple pressure parameters for micro-irrigation design[J].Biosystems Engineering,2005,90(4):463-475.
Srinivasa R K,Nagesh K D.Irrigation planning using genetic algorithms[J].Water Resources Management,2004,18(2):163-176.
Zella L,Kettab A.Numerical methods of microirrigation lateral design[J].Biotechnology,Agronomy,Society and Environment,2002,6(4):231-235.
王福军,王文娥.滴头流道CFD分析的研究进展与问题[J].农业工程学报,2006,22(7):188-192.Wang Fujun,Wang Wen'e.Research progress in analysis of flow passage in irrigation emitters using Computational Fluid Dynamics techniques[J].Transactions of the CSAE,2006,22(7):188-192.(in Chinese)
Mizyed N.Numerical analysis to solve the hydraulics of trickle irrigation units[J].Irrigation and Drainage Systerm,2002,16(1):53-68.
李云开,杨培岭,任树梅.滴灌灌水器流道设计理论研究若干问题的综述[J].农业机械学报,2006,37(2):145-149.Li Yunkai,Yang Peiling,Ren Shumei.General review on several fundamental points of design theory about flow path in drip irrigation emitters[J].Transactions of the Chinese Society for Agricultural Machinery,2006,37(2):145-149.(in Chinese)
王新坤.基于二分法的滴灌毛管水力设计[J].排灌机械,2007,25(6):27-30.Wang Xinkun.Hydraulic design of micro-irrigation laterals based on bisection method[J].Drainage and Irrigation Machinery,2007,25(6):27-30.(in Chinese)
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