State-space model for transient behavior of transport membrane condenser

Abstract

In this paper, a state-space model of a transport membrane condenser (TMC) based on a lumped heat and mass transfer model is developed and verified experimentally. The simulated results are in well agreement with the experimental data. Based on the state-space model, the transient relationships between the input parameters (inlet flue gas temperature and humidity ratio, inlet water temperature, flue gas and water flow rates), output parameters (outlet flue gas temperature and humidity ratio, outlet water temperature) and performance parameters (heat and water recovery fluxes, recovery efficiency) of the TMC are obtained and analyzed. It can be found that the perturbation of the flue gas flow rate has a larger effect on the heat and water recovery performances compared to that of the inlet flue gas humidity ratio. The performance parameters change by less than 1% with the inlet flue gas temperature step increasing from 50°C to 53°C. The inlet water parameters have significant effects on the performances. With the inlet water temperature step increasing from 15°C to 16°C, there is a hysteresis time in the response of the outlet water temperature. The comparative analysis based on the state-space model with a simply and rapid solution process can be used to determine the major input variables affecting the performances. The results are useful for the dynamic control of the TMC to obtain required stable performances.