【作者】 刘忠兵；

【导师】 张泠；

【作者基本信息】 湖南大学 ， 供热、供燃气、通风及空调工程， 2009， 硕士

【摘要】 基于热能贮存的热泵技术不仅能提高能源利用效率,而且能缓解能量供求双方在时间、强度和地点上的不匹配性,是合理利用能源及减轻环境污染的有效途径,在低温余热回收利用、电力的“移峰填谷”等领域具有显著的意义。传统的相变储能装置是利用余热热源与储能材料间的温差被动蓄热,因此不能根据余热排放情况调节蓄热速率,且在热能释放的过程中,难以根据能源使用端的要求实现热能的主动释放。本文在热电热泵热力学分析的基础上,利用热电热泵具有系统简单、无机械传动、无工质运行不污染环境等优点,创造性的提出了一种主动式的相变蓄热/放热新方法,设计制作了热电热泵相变蓄热/放热装置,并进行了实验研究表明,在蓄热时可根据余热排放时间长短和强度,通过改变输入电压大小调节蓄热速率实现主动蓄热;放热时,改变输入热电热泵的电流方向,通过调节输入电压,实现热能的主动释放。可利用的余热热源温度越高,蓄热时制热系数越大,在电压8V、余热热源温度在18℃~32℃之间时,蓄热时制热系数在1.14~2.23之间变化。放热时制热系数随取热流体温度的减小而增大,在电压4V、取热流体温度25℃左右,热电热泵在整个放热过程中制热系数在5.6~3.2之间变化。热电热泵相变蓄热/放热技术为余热回收、电力的“移峰填谷”、将间断能源如太阳能、风能等转化为连续能源方面等领域提供了新方法。本文还探讨了利用热电热泵回收气体余热制取卫生热水的可行性,并进行了实验研究。实验结果表明,在工作电压20V,余热热源温度大于26℃,热水温度小于46℃时热电热泵制热系数总是大于1。在此基础上,针对公共餐馆有大量热量需要排除而可供利用,同时又需要大量生活卫生热水的特点,结合热电热泵与热能贮存的原理,提出了一种利用热电热泵回收厨房排气余热制取卫生热水的方法并进行了实验研究。实验结果表明,把热水从28℃加热到46℃,在烟气温度33℃左右、工作电压20V时,系统能效系数为1.3以上,相比直接利用电制取热水计算,可节省电耗30%以上,且烟气温度越高,系统能效系数越高,节省电耗越多。利用热电热泵回收气体余热制取热水丰富了卫生热水的制取途径。更多还原

【Abstract】 The supply of thermal energy can not fulfil such a demand, in terms of the mismatch between energy supply and energy demands in quantity, location and time. In view of the efficiency of the energy utilization and energy-saving, a potential way is to use the heat pump with thermal energy storage, and it is of great practical interest in waste heat recovery, o? peak electricity storage and other fields.Traditional energy storage is passive process that cannot adjust the rate of heat charging and discharging. Thermoelectric systems do not require any compressor, expansion valves, absorbers, condensers or solution pumps, and moreover, they do not require working fluids employed in vapor-compression systems that are damaging to the environment. Based on the thermodynamic analysis on a thermoelectric heat pump system,a new active thermal storage system is introduced by means of integrating thermoelectric heat pump with latent heat storage in this paper. The work involved design and constrction of an active thermoelectric heat pump latent heat storage. The performance of the active latent heat storage was investigated under different work conditions. The experiment results show that the rate of the heat charging and discharging can be adjusted by changing the operating voltage of thermoelectric heat pump based on the time and the quantity of the waste heat when charging and the need of energy use when discharing. The higher the temperature of waste heat source is, the larger the coefficient of performance becomes. Under an operating voltage of 8V, the coefficient of performance decreases from 2.23 to 1.14 when the temperature of waste heat source decreases from 32℃to 18℃; The smaller the temperature of air is, the larger the coefficient of performance becomes when discharging process. Under an operating voltage of 4V and the temperature of air temperature is about 25℃, the coefficient of performance decreases from 5.6 to 3.2. Thermoelectric heat pump latent heat storage brings new ideas on waste recovery and off peak electricity storage, utilization of solar and other renewable energies.This paper also investigated the feasibility of heat recovery from exhaust by thermoelectric heat pump for water heating. Experiment verified that a thermoelectric heat pump system is more efficient than an electic heating decice, for its heating coefficient was always more than 1 when the temperature exhaust was higher than 26℃and the temperature of water was not higher than 46℃. On the base of the experiment data, a new kind of thermoelectric heat pump water heater for kitchens exhaust heat recovery was development by means of integrating thermoelectric heat pump with heat pipe heat sink. The higer the temperature of exhaust is, the larger the coefficient of performance becomes. Under an exhaust temperature of 33℃and operating voltage of 20V, performance tests illustrated that the new water heater can save more than 30% of the power consumption compared with that of conventional electric water heaters when the temperature of water increases from 28℃to 46℃. It is of great practical interest in building saving.更多还原