Study On Flow And Heat Transfer Performance Of Gas Turbine Intake Humidification Cooling

High temperature intake is an inevitable problem in summer operation of gas turbine power station.The increase of intake temperature leads to the decrease of gas turbine power.And the summer is the peak of electricity,the need for gas turbines to achieve and improve power generation.Therefore,reducing the gas turbine inlet temperature can effectively improve the output power of the gas turbine.Intake humidifying cooling has become one of the most promising gas turbine inlet cooling technologies due to its simple layout and high cost effectiveness.This paper studies how to achieve more effective gas turbine inlet humidification cooling effect,which has high engineering and scientific significance.In this paper,based on the basic thermodynamic process of water droplet evaporation in the process of inlet humidification,the humidification amount and temperature drop that can achieve the best humidification cooling effect under different atmospheric environment conditions are calculated and analyzed.Based on the single-drop evaporation theory,the inlet humidification cooling program was developed.The ideal humidification effect and evaporation time under different atmospheric environment conditions and different water droplet parameters are calculated,and the change of water droplets in the evaporation process is also calculated.The interaction effect of different parameters on evaporation time was analyzed by response surface method.The results show that the whole evaporation process can be divided into unsteady stage and steady stage.As the ambient temperature increased from 297.2K to 357.2K,the evaporation time decreased from 6.78 s to 1.54 s,and the temperature fluctuation at low temperature had a greater impact on the evaporation time.The evaporation time increased from 30μm to 100μm with the diameter of water droplets,from 0.25 s to 2.74 s.Large particle size fluctuations have a greater impact on evaporation time.The influence degree of three factors on evaporation time is: droplet diameter > ambient temperature > droplet temperature.There is a certain interaction between water droplet diameter and water droplet temperature,and the contribution rate can reach 8.53%.In this paper,the Euler-Lagrange method is used to numerically simulate the heat and mass transfer of gas/liquid two-phase in the humidification and cooling of intake air.Considering the influence of water droplet movement,fragmentation,evaporation,wall collision and other processes on inlet humidification,the temperature distribution,flow loss and water droplet movement law along the inlet humidification cooling path were analyzed by combining gas-liquid coupling and variable specific heat calculation.The air humidification scheme was optimized by using the air humidification cooling program,and the cooling performance before and after optimization was compared.The effects of water droplet diameter,water droplet temperature,injection direction and atmospheric temperature on the inlet humidification cooling performance were analyzed.The interaction effect of different humidification parameters on the cooling rate was analyzed by response surface method,and the final humidification scheme was obtained.The cooling performance of the final humidification scheme and the initial humidification scheme was compared and analyzed.The results show that the inlet temperature of compressor can be effectively reduced by inlet humidification cooling.For a certain type of gas turbine power station,the inlet temperature is reduced from 323.2K in dry condition to 300.3K in design wet condition,and the humidification has no obvious effect on the total pressure loss.There is interaction between droplet size and droplet temperature.When the droplet size is constant,with the increase of droplet temperature,the total outlet temperature decreases first and then increases,but the extreme position moves to high temperature water droplets with the increase of droplet size.When the humidification amount is 1.83 kg/s,the droplet size is 30μm,and the droplet temperature is 288.45 K,the humidification effect is the best.The outlet temperature can be reduced to 292.0K.