scholarly journals Determination Of Thermal Parameters Of Solar Water Heating Collectors Using The “Dark” Testing Method

2020 ◽  
Vol 02 (11) ◽  
pp. 62-67
Author(s):  
Nizomjon Orifovich Usmonov ◽  
◽  
Xayrulla Sunnatullaevich Isakhojaev ◽  
Saodat Rakhsulaevna Akhmatova ◽  
Feruza Abdullaevna Khoshimova ◽  
...  
Keyword(s):  
Thermal Characteristics ◽  
Hot Water ◽  
Thermal Testing ◽  
Water Heating ◽  
Solar Water Heating ◽  
Solar Water ◽  
Testing Method ◽  
Hot Water Supply ◽  
Hot Water Supply System

In the production of flat solar water heating collectors, thermal testing occupies a special place, the purpose of which is to determine their thermal characteristics experimentally. The corresponding approximation expressions are proposed for determining the coefficient of heat loss, inclined to the horizon at an angle of 300 for the average conditions of their operation in the hot water supply system

Resource indexes of flat solar water-heating collectors in hot-water supply systems: 4. Specific collector thermal yield and efficiency

2013 ◽  
Vol 49 (4) ◽  
pp. 202-210 ◽  
Author(s):  
N. R. Avezova ◽  
R. R. Avezov ◽  
N. T. Rustamov ◽  
A. Vakhidov ◽  
Sh. I. Suleymanov
Keyword(s):  
Water Supply ◽  
Hot Water ◽  
Water Supply Systems ◽  
Water Heating ◽  
Solar Water Heating ◽  
Solar Water ◽  
Hot Water Supply ◽  
Supply Systems

scholarly journals Economic assessment and optimizing of the solar water heating system

2018 ◽  
Vol 210 ◽  
pp. 02023
Author(s):  
Jan Skovajsa ◽  
Martin Zálešák
Keyword(s):  
Solar System ◽  
Optimal Solution ◽  
Heating System ◽  
Hot Water ◽  
Design Parameters ◽  
Optimal Parameters ◽  
Water Heating ◽  
Solar Water Heating ◽  
Solar Water ◽  
Solar Water Heating System

The article deals with the economic evaluation of investment and optimization of the solar water heating system for family houses. From the point of view of solar systems, the optimal solution is based on the specific application of it. The design is dependent on the location of solar thermal collectors and ration between active aperture area and real daytime consumption. Common calculations according to actual standards often give overstated results, which also reflected in the value of the investments. The article presents the research of optimal parameters of the thermal solar system for preparing of domestic hot water. A combination of related standards and software TRNSYS are used to find optimal parameters. Thanks to created and verified simulation models, it is possible to design parameters so as to avoid under-dimensioning or over-dimensioning of the solar system. Energy price is another factor affects the payback period of investments. This is affected by the used energy sources and their combination. For example, buildings that use electricity to heat water or heating have different energy charges than a building that uses natural gas. So, the aim is to find technically and economically efficient solution.

A Second Law Approach to Characterising Thermally Stratified Hot Water Storage With Application to Solar Water Heaters

1999 ◽  
Vol 121 (4) ◽  
pp. 194-200 ◽  
Author(s):  
G. Rosengarten ◽  
G. Morrison ◽  
M. Behnia
Keyword(s):  
Temperature Distribution ◽  
Heat Exchangers ◽  
Water Storage ◽  
Heating System ◽  
Hot Water ◽  
Effect Of Temperature ◽  
Storage Efficiency ◽  
Water Heating ◽  
Solar Water Heating ◽  
Solar Water

This paper presents a method of characterising and evaluating the performance of hot water storage systems in terms of their temperature distribution. The change in exergy from the stratified state to the delivery state depends on the stored energy and the stratification. It can thus he used to define the storage efficiency for sensible heat storage devices. A new parameter that isolates the stratification component of the exergy is defined and called the stratification efficiency. The effect of temperature distribution, delivery temperature and tank cross-section on exergy and stratification efficiency is investigated. The advantage that stratification offers over a mixed tank is examined in terms of the storage efficiency and overall solar water heating system performance. Exergy is used to assess the operation of mantle heat exchangers in solar water heating systems and it is shown that exergy and stratification efficiency, as well as energy, should be used to ascertain the performance of such heat exchangers.

Solar Water Heaters: A Review of Systems Research and Design Innovation

Green ◽  
2011 ◽  
Vol 1 (2) ◽  
Author(s):  
Brian Norton
Keyword(s):  
System Development ◽  
Unit Cost ◽  
Hot Water ◽  
Water Heating ◽  
Water Heater ◽  
Solar Water Heating ◽  
Solar Water ◽  
Water Heaters ◽  
Systems Research ◽  
And Performance

AbstractSolar water heating can be considered to be an established mature technology. The achievement of this status is the outcome of over a century of system development that culminated with a flourish of innovation in the last thirty years. Drivers for research and development have been achieving economic viability by devising systems that, for specific applications in particular climate contexts produced more hot water per unit cost. Reductions in both initial capital and installation costs have been achieved as well as in those associated with subsequent operation and maintenance. Research on solar water heating is discussed with the emphasis on overall systems though some key aspects of component development are also outlined. A comprehensive taxonomy is presented of the generic types of solar water heater that have emerged and their features, characteristics and performance are discussed.

Joint Application of Solar Water Heating System and Air-Conditioning System in a Dormitory Building

2010 ◽  
Vol 171-172 ◽  
pp. 215-218
Author(s):  
Hai Ying Wang ◽  
Song Tao Hu ◽  
Jia Ping Liu
Keyword(s):  
Air Conditioning ◽  
Heating System ◽  
Hot Water ◽  
Water Tank ◽  
Auxiliary Heating ◽  
Water Heating ◽  
Air Conditioning System ◽  
Solar Water Heating ◽  
Solar Water ◽  
Solar Water Heating System

Solar water heating system is used to supply hot water all-year-round for a new dormitory building. Flat solar energy collectors are mounted on the roof. The hot water tank and pumps are installed together with the air conditioning equipments in the plant room. Air cooled heat pump is used to provide cooling in summer, and high temperature water from boiler room (in old building) is used as heat source in winter. Usually auxiliary heating is necessary to improve the stability and reliability of solar water heating system. In this case, we take full use of the equipment of air conditioning system instead of electricity as auxiliary heating resources. In this paper, we introduced the design of the solar water heating system and the auxiliary heating method by air conditioning systems. The control strategies to fulfill all the functions and switch between different conditions are also introduced.

A Review of Polymer Materials for Solar Water Heating Systems

2000 ◽  
Vol 122 (2) ◽  
pp. 92-100 ◽  
Author(s):  
Raghu Raman ◽  
Susan Mantell ◽  
Jane Davidson ◽  
Chunhui Wu ◽  
Gary Jorgensen
Keyword(s):  
High Temperature ◽  
Heat Exchanger ◽  
Uv Light ◽  
Solar Spectrum ◽  
Hot Water ◽  
Polymer Materials ◽  
Water Heating ◽  
Heating Systems ◽  
Solar Water Heating ◽  
Solar Water

This paper summarizes current research aimed at using polymer materials for glazing and heat exchanger components in solar water heating systems. Functional requirements, relevant polymer properties and an approach for selecting polymers are described for each of these components. Glazing must have high transmittance across the solar spectrum and withstand long term exposure to ultraviolet (UV) light. Candidate glazing materials were tested outdoors for one year in Golden, Phoenix and Miami, as well as exposed for over 300 days in an accelerated testing facility at a concentration ratio of two at the National Renewable Energy Laboratory. Measurements of hemispherical transmittance indicate that a 3.35 mm polycarbonate sheet with a thin film acrylic UV screen provides good transmittance without excessive degradation. The primary challenge to designing a polymer heat exchanger is selecting a polymer that is compatible with potable water and capable of withstanding the high pressure and temperature requirements of domestic hot water systems. Polymers certified for hot water applications by the National Sanitation Foundation or currently used in heat exchangers and exhibit good high temperature characteristics were compared on the basis of a merit value (thermal conductance per unit area per dollar) and manufacturer’s recommendations. High temperature nylon (HTN), polypropylene (PP) and cross linked polypropylene (PEX) are recommended for tube components. For structural components (i.e. headers), glass reinforced high temperature nylon (HTN), polyphthalamide (PPA), polyphenylene sulphide (PPS) and polypropylene (PP) are recommended. [S0199-6231(00)00902-3]

Experimental Research on a Novel Solar Water Heating System by Using Loop Heat Pipe

2013 ◽  
Vol 724-725 ◽  
pp. 163-170
Author(s):  
Zhang Yuan Wang ◽  
Xiang Mei Zhang ◽  
Wan Sheng Yang ◽  
Zhi Wu Chen
Keyword(s):  
Heat Pipe ◽  
High Efficiency ◽  
Heating System ◽  
Hot Water ◽  
Loop Heat Pipe ◽  
Water Heating ◽  
Solar Water Heating ◽  
Solar Water ◽  
Evacuated Tubes ◽  
Solar Water Heating System

In this paper, a novel solar water heating system will be proposed by applying the loop heat pipe to a conventional split solar hot water system, which will have the characteristics of high efficiency, low cost, appearance appealing and building integration. Three types of the system, i.e., the system with evacuated tubes, with single flat-plate glazing cover, and without glazing, will be experimentally investigated and compared on the influence to the dynamic performance of the system. It was found that the system’s operating temperature increased significantly during the start-up stage and gently after until reach relatively constant. The instantaneous efficiency was found to be fluctuated, although it reached stable eventually during the operations for all three types. By using the moving average calculating method, every 10 minutes were applied for the calculation of the average efficiency which had a negative linear relation with the combined factor of (Tmean-Tamb)/I. In general, the solar system with evacuated tubes performed the best with the highest water temperature output, highest system efficiency and lowest heat loss coefficient among the three systems.

Sign in / Sign up

Export Citation Format

Share Document