间歇波动性低温热源混合工质冷电联供系统集成和调控机理研究

Utilizing the behavior of temperature glide of non-azeotropic mixture during the two-phase region could achieve multiple energy conversion for the interval and fluctuant low temperature heat source. It is significant to obtain energy saving and low consumption and control the occurrence of haze weather.it is fundamental for effective energy conversion to establish the integration method of multiple energy conversion system using mixture working fluid and ensure the optimum coordinated operation of system. This program will examine optimal thermodynamic match of the pocess of energy trasportion, energy storage and conversion, and establish the integration method of combined cooling and power system driven by low temperature heat source using mixture working fluid based on the principle of minimum energy dissipation to meet the dual requirement of cooling and power, achieving the promotion of energy grade. Furthermore, it will explore the dynamic response of the key parameters of the combined system when the mass flow rate and temperature of heat source, the load of cooling and electricity of the combined system are subjected to a change. It will demonstrate the space-time evolvement behavior of energy transportion and conversion in the combined system. In addition, it will explore the adjusting mechanisim of ammonia mass fraction during the process of energy conversion. It also will reveal the coordinated control mechanism of combined cooling and power system using mixture working fluid to obtain the optimum coordinated operation behavior with multiple evaluation criterions, achieving the effective operation of system. The program could help enrich and improve the theory of energy system integration with multiple energy output, which has an important academic significance application prospect.

利用非共沸混合工质在两相区的温度滑移特性，能够实现间歇波动性低温热源的多能量输出转换，对于节能降耗和抑制雾霾天气具有重要意义。建立混合工质多能量输出系统集成方法并且确保系统协调优化运行，是实现能量高效转换的根本。项目通过对间歇波动性低品位能量传输、储存、转换过程最佳热力匹配特性研究，以能量耗散最小为原则，建立间歇波动性低温热源混合工质冷电联供系统集成方法，满足用户对冷电的双重需求，实现能量品质提升；探究低温热源流量、温度以及冷、电负荷变化时，混合工质冷电联供系统关键热力参数的动态响应规律，阐明混合工质冷电联供系统中能量传输、储存、转换过程的时空演变规律；探索混合工质组分对热功/热冷转换过程的调控机理，阐明混合工质冷电联供系统协调控制机理，揭示多准则评价指标下系统的最优化协调运行特性，实现系统高效灵活运行。项目有助于丰富和完善多能量输出能源系统集成理论，具有重要的理论和学术意义及应用前景。

工业生产过程和自然界中存在大量的间歇波动性低温热源。针对这些低温热源，利用混合工质在两相区温度滑移特性实现能量高效传输和转换，既可以节能减排，降低环境污染；又能提升能源利用率，缓解电网压力。为此，提出间歇波动性低温热源混合工质冷电联供系统，实现“按质用能，逐级利用”的能源梯级利用目标。.根据热源波动特性，引入蓄热机制以平抑热源波动，使热源输出更加稳定。按照“工质通用，部件共享”的耦合原理将动力循环与制冷循环进行耦合，构建了四种基于低温波动性热源的混合工质冷电联供系统。建立混合工质选择准则，从环境友好、可混合性和温度滑移特性等方面综合考虑选择适合系统的混合工质，建立混合工质冷电联供系统数学模型，搭建系统热力学仿真分析平台，研究关键热力学参数（如透平进口温度、透平进口压力、工质浓度和冷凝温度等）对系统性能的影响规律，从热力学性能和热经济学性能对系统进行评估，建立能够综合描述、全面评价间歇波动性低温热源混合工质冷电联供系统热力学性能和投资运行经济性的经济性评价模型和指标。结合系统初期投资成本和运行费用，采用智能算法对系统进行全局优化，获得系统的最佳运行参数和投资运行费用，实现间歇波动性低温热源混合工质冷电联供系统优化、经济运行。. 在研究间歇波动性低温热源混合工质冷电联供系统稳态工况的基础之上，建立混合工质冷电联供系统动态数学模型，提出了混合工质冷电联供系统协调控制策略，研究了热源温度、热源流量、冷负荷、电负荷变化发生扰动时对系统参数的动态响应过程，获得了系统循环吸热量、输出功率、输出制冷量和循环发热量的协调变化规律，能够提高系统的适应性、稳定性和鲁棒性。