The principle and development prospect of air source heat pump water heat were introduced,as well as the designation of condenser (storage water tank),experimental study on installations was also carried out.The resul...The principle and development prospect of air source heat pump water heat were introduced,as well as the designation of condenser (storage water tank),experimental study on installations was also carried out.The results showed that air source heat pump water heater was superior to conventional system.Under the operation of cooling and heating,heat pump comprehensive utilization equipment could improve heating performance,reduce energy consumption,and recycle condensing heat to provide hot water.展开更多
Water source heat pump is a new kind of energy saving process.One of the most common problems for water source heat pump system is the corrosion of the copper in heat exchanger.The quality of water is the key factor.T...Water source heat pump is a new kind of energy saving process.One of the most common problems for water source heat pump system is the corrosion of the copper in heat exchanger.The quality of water is the key factor.The river water collected in six different places of the Yangtze River and Jialing River in Chongqing were analyzed.Various parameters(pH,coexisted ions,and hardness value)were investigated.It showed that the Yangtze River and Jialing River water was suitable for developing water source heat pump technology.Further more,aimed at the temperature and pH of the raw water's variation range in a year,the corrosion behavior of copper material was studied by controlling the water environmental condition.Corrosion rate of copper is accelerated at high temperature and lower pH value.展开更多
A new type of microchannel condenser applied in the air source heat pump water heater(ASHPWH)with cyclic heating was proposed in this study.The operating performance of the ASHPWH was frst tested.Then,the structure of...A new type of microchannel condenser applied in the air source heat pump water heater(ASHPWH)with cyclic heating was proposed in this study.The operating performance of the ASHPWH was frst tested.Then,the structure of the microchannel condenser was optimized with the implement of vortex generators.Finally,a numerical model of the ASHPWH was established and the optimized microchannel condenser was studied.The experimental results showed that the average coefficient of performance(COP)of the 1HP(735 W)ASHPWH reached 3.48.In addition,the optimized microchannel condenser could be matched with a 3 HP(2430W)ASHPWH with an average heating capacity of 10.30 kW,and achieving an average COP of 4.24,14.6%higher than the limit value in the national standard.展开更多
Natural energy use is important to reduce the energy consumption of buildings. However, further reducing energy consumption with traditional systems is difficult. Therefore, we proposed a MMHP (multi-source and multi...Natural energy use is important to reduce the energy consumption of buildings. However, further reducing energy consumption with traditional systems is difficult. Therefore, we proposed a MMHP (multi-source and multi-use heat pump) to achieve higher efficiency than traditional systems. The MMHP system connects multiple heat sources such as solar heat, the ground, and air and multiple heat uses such as cooling, heating, and a hot water dispenser with a water loop. Each type of heat use side can utilize heat efficiently. However, there is a distinct lack of highly efficient hot water dispensers available. Therefore, we developed the IHWD WS (instantaneous hot water dispenser based on a water source) heat pump. In this study, we developed a prototype of the IHWD WS heat pump. The coefficient of performance of the IHWD WS heat pump was 5.2-8.5 throughout a year. When it is improved, COP (coefficient of performance) is expected to be 9.3-9.9.展开更多
Drinking water is closely related to human health,disease and mortality,and contaminated drinking water causes 485,000 deaths from diarrhea each year worldwide.China has been facing increasingly severe water scarcity ...Drinking water is closely related to human health,disease and mortality,and contaminated drinking water causes 485,000 deaths from diarrhea each year worldwide.China has been facing increasingly severe water scarcity due to both water shortages and poor water quality.Ensuring safe and clean drinking water is a great challenge and top priority,especially for China with 1.4 billion people.In China,more than 4000 centralized drinking water sources including rivers,lakes and reservoirs,and groundwater have been established to serve urban residents.However,there is little knowledge on the percentage,serving population and water quality of three centralized drinking water source types.We collected nationwide centralized drinking water sources data and serving population data covering 395 prefecture-level and county-level cities and water quality data in the two most populous provinces(Guangdong and Shandong)to examine their contribution and importance.Geographically,the drinking water source types can be classified into three clear regions exhibiting apparent differences in the respective contributions of rivers,lakes and reservoirs,and groundwater.We further found that overall,lakes and reservoirs account for 40.6%of the centralized drinking water sources vs.river(30.8%)and groundwater(28.6%)in China.Lakes and reservoirs are particularly important in the densely populated eastern region,where they are used as drinking water sources by 51.0%of the population(318 million).Moreover,the contribution to the drinking water supply from lakes and reservoirs is increasing due to their better water quality and many cross-regional water transfer projects.These results will be useful for the government to improve and optimize the establishment of centralized drinking water sources,which provide safe and clean drinking water in China to safeguard people's lives and health and realize sustainable development goals.展开更多
太阳能-空气源热泵热水系统(solar-air source heat pump hot water system, SAHWS)常用于宿舍楼宇供暖,通过对系统参数的优化设计可显著提高系统能效性能与环境友好性。为得到一种综合考虑SAHWS经济、能源、环保与节能的优化方法,提出...太阳能-空气源热泵热水系统(solar-air source heat pump hot water system, SAHWS)常用于宿舍楼宇供暖,通过对系统参数的优化设计可显著提高系统能效性能与环境友好性。为得到一种综合考虑SAHWS经济、能源、环保与节能的优化方法,提出了一种新型组合优化设计策略,并利用TRNSYS软件搭建系统仿真模型,以西安、西宁、拉萨这3座不同太阳能资源等级城市为例,对SAHWS运行工况对比分析。结果表明:与常用生命周期成本设计相比,所提出的组合优化设计不仅降低了系统成本,还有着较低的系统能耗;组合优化设计的热泵能耗与工作小时数最短,且有最低的热损,在投资成本、系统季节性能因子、太阳能保证率以及碳粉尘、二氧化碳排放量均有较好表现。展开更多
The studies on predicting the energy consumption of air conditioning systems are meaningful to building energy conservation and management. Generally, the more comprehensive the building information is, the easier the...The studies on predicting the energy consumption of air conditioning systems are meaningful to building energy conservation and management. Generally, the more comprehensive the building information is, the easier the prediction model can be developed. However, it is very difficult to get detailed information about existing/old buildings (information-poor buildings), it is a big challenge to predict the energy consumption accurately by limited information. This study aims to predict the electricity consumption of the water source heat pump system of an office building based on meteorological data. The key variables are selected by error analysis and sensitivity analysis, and the effects of each variable on the models’ prediction performance can be obtained. Besides, the prediction models are established by support vector regression algorithm and trained by the local meteorological data. The results show that the positive and negative variables can be identified, and these positive variables are responsible for more than 70% of the total importance. Moreover, the root mean square error falls to 4.6044 from 7.8227 and the relative square error falls to 0.1494 from 0.4313 when the negative inputs are removed. And the errors reduce further to 4.1160 and 0.1194 by parameter optimization.展开更多
基金Supported by Scientific Research Fund of Ningxia University [(E) ndzr09-23]
文摘The principle and development prospect of air source heat pump water heat were introduced,as well as the designation of condenser (storage water tank),experimental study on installations was also carried out.The results showed that air source heat pump water heater was superior to conventional system.Under the operation of cooling and heating,heat pump comprehensive utilization equipment could improve heating performance,reduce energy consumption,and recycle condensing heat to provide hot water.
基金supported by the China Postdoctoral Science Foundation(20080430747)foundation of Chongqing University Young Talents for Promoting the Innovative Force(qnjj2008-7)
文摘Water source heat pump is a new kind of energy saving process.One of the most common problems for water source heat pump system is the corrosion of the copper in heat exchanger.The quality of water is the key factor.The river water collected in six different places of the Yangtze River and Jialing River in Chongqing were analyzed.Various parameters(pH,coexisted ions,and hardness value)were investigated.It showed that the Yangtze River and Jialing River water was suitable for developing water source heat pump technology.Further more,aimed at the temperature and pH of the raw water's variation range in a year,the corrosion behavior of copper material was studied by controlling the water environmental condition.Corrosion rate of copper is accelerated at high temperature and lower pH value.
基金the National Natural Science Foundation of China(No.51776117)。
文摘A new type of microchannel condenser applied in the air source heat pump water heater(ASHPWH)with cyclic heating was proposed in this study.The operating performance of the ASHPWH was frst tested.Then,the structure of the microchannel condenser was optimized with the implement of vortex generators.Finally,a numerical model of the ASHPWH was established and the optimized microchannel condenser was studied.The experimental results showed that the average coefficient of performance(COP)of the 1HP(735 W)ASHPWH reached 3.48.In addition,the optimized microchannel condenser could be matched with a 3 HP(2430W)ASHPWH with an average heating capacity of 10.30 kW,and achieving an average COP of 4.24,14.6%higher than the limit value in the national standard.
文摘Natural energy use is important to reduce the energy consumption of buildings. However, further reducing energy consumption with traditional systems is difficult. Therefore, we proposed a MMHP (multi-source and multi-use heat pump) to achieve higher efficiency than traditional systems. The MMHP system connects multiple heat sources such as solar heat, the ground, and air and multiple heat uses such as cooling, heating, and a hot water dispenser with a water loop. Each type of heat use side can utilize heat efficiently. However, there is a distinct lack of highly efficient hot water dispensers available. Therefore, we developed the IHWD WS (instantaneous hot water dispenser based on a water source) heat pump. In this study, we developed a prototype of the IHWD WS heat pump. The coefficient of performance of the IHWD WS heat pump was 5.2-8.5 throughout a year. When it is improved, COP (coefficient of performance) is expected to be 9.3-9.9.
基金supported by the National Natural Science Foundation of China (41790423,41930760,and 41621002)the Key Research Program of Frontier Sciences,Chinese Academy of Sciences (QYZDB-SSW-DQC016)Erik Jeppesen was supported by the Tübitak program BIDEB 2232 (project 118C250).
文摘Drinking water is closely related to human health,disease and mortality,and contaminated drinking water causes 485,000 deaths from diarrhea each year worldwide.China has been facing increasingly severe water scarcity due to both water shortages and poor water quality.Ensuring safe and clean drinking water is a great challenge and top priority,especially for China with 1.4 billion people.In China,more than 4000 centralized drinking water sources including rivers,lakes and reservoirs,and groundwater have been established to serve urban residents.However,there is little knowledge on the percentage,serving population and water quality of three centralized drinking water source types.We collected nationwide centralized drinking water sources data and serving population data covering 395 prefecture-level and county-level cities and water quality data in the two most populous provinces(Guangdong and Shandong)to examine their contribution and importance.Geographically,the drinking water source types can be classified into three clear regions exhibiting apparent differences in the respective contributions of rivers,lakes and reservoirs,and groundwater.We further found that overall,lakes and reservoirs account for 40.6%of the centralized drinking water sources vs.river(30.8%)and groundwater(28.6%)in China.Lakes and reservoirs are particularly important in the densely populated eastern region,where they are used as drinking water sources by 51.0%of the population(318 million).Moreover,the contribution to the drinking water supply from lakes and reservoirs is increasing due to their better water quality and many cross-regional water transfer projects.These results will be useful for the government to improve and optimize the establishment of centralized drinking water sources,which provide safe and clean drinking water in China to safeguard people's lives and health and realize sustainable development goals.
文摘太阳能-空气源热泵热水系统(solar-air source heat pump hot water system, SAHWS)常用于宿舍楼宇供暖,通过对系统参数的优化设计可显著提高系统能效性能与环境友好性。为得到一种综合考虑SAHWS经济、能源、环保与节能的优化方法,提出了一种新型组合优化设计策略,并利用TRNSYS软件搭建系统仿真模型,以西安、西宁、拉萨这3座不同太阳能资源等级城市为例,对SAHWS运行工况对比分析。结果表明:与常用生命周期成本设计相比,所提出的组合优化设计不仅降低了系统成本,还有着较低的系统能耗;组合优化设计的热泵能耗与工作小时数最短,且有最低的热损,在投资成本、系统季节性能因子、太阳能保证率以及碳粉尘、二氧化碳排放量均有较好表现。
基金This work was supported by the National Natural Science Foundation of China(No.51876070,No.51576074).
文摘The studies on predicting the energy consumption of air conditioning systems are meaningful to building energy conservation and management. Generally, the more comprehensive the building information is, the easier the prediction model can be developed. However, it is very difficult to get detailed information about existing/old buildings (information-poor buildings), it is a big challenge to predict the energy consumption accurately by limited information. This study aims to predict the electricity consumption of the water source heat pump system of an office building based on meteorological data. The key variables are selected by error analysis and sensitivity analysis, and the effects of each variable on the models’ prediction performance can be obtained. Besides, the prediction models are established by support vector regression algorithm and trained by the local meteorological data. The results show that the positive and negative variables can be identified, and these positive variables are responsible for more than 70% of the total importance. Moreover, the root mean square error falls to 4.6044 from 7.8227 and the relative square error falls to 0.1494 from 0.4313 when the negative inputs are removed. And the errors reduce further to 4.1160 and 0.1194 by parameter optimization.