scholarly journals Study on the Adaptability of Extracting Steam and Heat Return Pipe System of Heating Unit

2021 ◽  
Vol 11 (2) ◽  
pp. 71
Author(s):  
Liming Zhai ◽  
Yaosen Chen ◽  
Zhiwei Li ◽  
Xiaochen Chen ◽  
Jiongming Wang ◽  
...  
Keyword(s):  
Heat Pipe ◽  
Heating System ◽  
Scientific Basis ◽  
Design Parameters ◽  
Actual Situation ◽  
Heating Unit ◽  
Flow Rates ◽  
Pipe System ◽  
Heating Capacity ◽  
Before And After

In view of the insufficient heating capacity of a supercritical 600 WM unit, it is necessary to determine whether the equipment of the extraction and return heat pipe system can operate normally after the transformation, so as to check the adaptability of the extraction and return heat pipe system equipment of the heating unit. Based on the actual situation and heat balance before and after the transformation of the heating system, this study selects the extracting steam and heat return pipe system of the heating units at all levels, and makes adaptive accounting from the design parameters of the pipeline, and the calculations of steam flow rates or pipe diameters of the pipeline, which provide scientific basis and evaluation for the feasibility of the retrofit scheme.

Heat Pipe Augmented Solar Heating System

2010 ◽  
Author(s):  
Brian S. Robinson ◽  
Michael V. Albanese ◽  
Nick Chmielewski ◽  
Ellen G. Brehob ◽  
M. Keith Sharp
Keyword(s):  
Heat Pipe ◽  
Heating System ◽  
Solar Heating ◽  
System Component ◽  
Laboratory Model ◽  
Small Scale ◽  
Concrete Wall ◽  
Pipe System ◽  
Passive Solar ◽  
The One

The focus of this project is on simulation and testing of a novel passive solar heating system that utilizes the one-way heat transfer of heat pipes to significantly improve heating performance relative to conventional passive solar systems. A set of programmed thermal networks were used to simulate the performance of several conventional passive solar heating systems, including direct gain, concrete wall indirect gain and water wall indirect gain, and the heat pipe system. Simulations performed for four US locations representing a range of winter temperatures and available insolation exhibited higher performance for the heat pipe system, particularly in cold climates with low insolation. A small-scale laboratory model was constructed and tested under controlled conditions to confirm simulated system component performance and to test a range of component variations. Measured system efficiency was 85.1 ± 0.72%. A full-scale prototype was constructed, installed and instrumented. Results from a 21-day period in April show a prototype thermal efficiency range from 60–75% and an average of 66.2%; and a 30-day period in October and November ranges from 60–85% with an average of 73.9%. An opaque cover over the prototype, periodically installed to minimize unwanted gains during the cooling season, reduced overall gains by an average of 75%.

scholarly journals Theoretical analysis and experimental research of heat pump driving heat pipes heating equipment

2020 ◽  
Vol 24 (2 Part A) ◽  
pp. 1019-1029
Author(s):  
Ruochen Ding ◽  
Baorui Du ◽  
Shuxue Xu ◽  
Jun Yao ◽  
Huilong Zheng
Keyword(s):  
Heat Pipe ◽  
Heat Pump ◽  
Composite System ◽  
Working Condition ◽  
Heat Pipes ◽  
Design Parameters ◽  
Heating Equipment ◽  
Start Up ◽  
Heating Capacity ◽  
Operation Characteristics

In this study, the main design parameters of the heat pump/heat pipe composite system were calculated. The operation characteristics of the heat pump/heat pipe composite system under low temperature were experimentally studied. The start-up character of the heat pipe radiator and heat pipe radiator surface temperature distribution were obtained. The variation of heating capacity and heating coefficient of performaance of the heat pump/heat pipe composite system with different working condition was obtained. Experimental results show that the heat pump/heat pipe composite system can operate efficiently and steadily when the outdoor temperature is ?20~5?C, and meet the winter heating demand in cold areas.

Thermal-Vacuum Test Data For Jem/Maxi Loop Heat Pipe System With Two Radiators

2008 ◽  
Author(s):  
Shiro Ueno ◽  
Dmitry Khrustalev ◽  
Peter Cologer ◽  
Russ Snyder
Keyword(s):  
Heat Pipe ◽  
Test Data ◽  
Loop Heat Pipe ◽  
Thermal Vacuum ◽  
Pipe System ◽  
Vacuum Test

Fabrication, modeling, and characterization of soft twisting electrothermal actuators with directly printed oblique heater

2022 ◽  
Author(s):  
Yang Cao ◽  
Jingyan Dong
Keyword(s):  
Kinematic Model ◽  
Design Parameters ◽  
Deformation Analysis ◽  
Pdms Layer ◽  
Element Analysis ◽  
Electrothermal Actuators ◽  
Bending Deformation ◽  
Heating Capacity ◽  
Twisting Angle ◽  
Twisting Deformation

Abstract Soft electrothermal actuators have drawn extensive attention in recent years for their promising applications in biomimetic and biomedical areas. Most soft electrothermal actuators reported so far demonstrated uniform bending deformation, due to the deposition based fabrication of the conductive heater layer from nanomaterial-based solutions, which generally provides uniform heating capacity and uniform bending deformation. In this paper, a soft electrothermal actuator that can provide twisting deformation was designed and fabricated. A metallic microfilament heater of the soft twisting actuator was directly printed using electrohydrodynamic (EHD) printing, and embedded between two structural layers, a polyimide (PI) film and a polydimethylsiloxane (PDMS) layer, with distinct thermal expansion properties. Assisted by the direct patterning capabilities of EHD printing, a skewed heater pattern was designed and printed. This skewed heater pattern not only produces a skewed parallelogram-shaped temperature field, but also changes the stiffness anisotropy of the actuator, leading to twisting deformation with coupled bending. A theoretical kinematic model was built for the twisting actuator to describe its twisting deformation under different actuation effects. Based on that model, influence of design parameters on the twisting angle and motion trajectory of the twisting actuator were studied and validated by experiments. Finite element analysis (FEA) was utilized for the thermal and deformation analysis of the actuator. The fabricated twisting actuator was characterized on its heating and twisting performance at different supply voltages. Using three twisting actuators, a soft gripper was designed and fabricated to implement pick-and-place operations of delicate objects.

Analysis on energy efficiency of an integrated heat pipe system in data centers

2015 ◽  
Vol 90 ◽  
pp. 937-944 ◽  
Author(s):  
Zhenying Wang ◽  
Xiaotong Zhang ◽  
Zhen Li ◽  
Ming Luo
Keyword(s):  
Energy Efficiency ◽  
Heat Pipe ◽  
Data Centers ◽  
Pipe System

scholarly journals Modified High Back-Pressure Heating System Integrated with Raw Coal Pre-Drying in Combined Heat and Power Unit

Energies ◽  
2018 ◽  
Vol 11 (9) ◽  
pp. 2487 ◽  
Author(s):  
Heng Chen ◽  
Zhen Qi ◽  
Qiao Chen ◽  
Yunyun Wu ◽  
Gang Xu ◽  
...  
Keyword(s):  
Power Generation ◽  
Flue Gas ◽  
Waste Heat ◽  
Heating System ◽  
Combined Heat And Power ◽  
Back Pressure ◽  
Coal Consumption ◽  
Heating Capacity ◽  
Boiler Efficiency ◽  
Saving Effect

A conceptual high-back pressure (HBP) heating system cooperating raw coal pre-drying for combined heat and power (CHP) was proposed to improve the performance of the HBP-CHP unit. In the new design, besides of heating the supply-water of the heating network, a portion of the exhaust steam from the turbine is employed to desiccate the raw coal prior to the coal pulverizer, which further recovers the waste heat of the exhaust steam and contributes to raising the overall efficiency of the unit. Thermodynamic and economic analyzes were conducted based on a typical 300 MW coal-fired HBP-CHP unit with the application of the modified configuration. The results showed that the power generation thermal efficiency promotion of the unit reaches 1.7% (absolute value) owing to suggested retrofitting, and meanwhile, the power generation standard coal consumption rate is diminished by 5.8 g/kWh. Due to the raw coal pre-drying, the energy loss of the exhaust flue gas of the boiler is reduced by 19.1% and the boiler efficiency increases from 92.7% to 95.4%. The impacts of the water content of the dried coal and the unit heating capacity on the energy-saving effect of the new concept were also examined.

Evacuated Tube Heat Pipe Solar Collectors Applied to Recirculation Loop in a Federal Building: SSA Philadelphia

Solar Energy ◽  
2004 ◽  
Author(s):  
Andy Walker ◽  
Fariborz Mahjouri ◽  
Robert Stiteler
Keyword(s):  
Solar Energy ◽  
Heat Pipe ◽  
Heat Loss ◽  
Heating System ◽  
Hot Water ◽  
Solar Array ◽  
Solar Collectors ◽  
Water Heating ◽  
Evacuated Tube ◽  
Recirculation Loop

This paper describes design, simulation, construction and measured initial performance of a solar water heating system (360 Evacuated Heat-Pipe Collector tubes, 54 m2 gross area, 36 m2 net absorber area) installed at the top of the hot water recirculation loop in the Social Security Mid-Atlantic Center in Philadelphia. Water returning to the hot water storage tank is heated by the solar array when solar energy is available. This new approach, as opposed to the more conventional approach of preheating incoming water, is made possible by the thermal diode effect of heat pipes and low heat loss from evacuated tube solar collectors. The simplicity of this approach and its low installation costs makes the deployment of solar energy in existing commercial buildings more attractive, especially where the roof is far removed from the water heating system, which is often in the basement. Initial observed performance of the system is reported. Hourly simulation estimates annual energy delivery of 111 GJ/year of solar heat and that the annual efficiency (based on the 54 m2 gross area) of the solar collectors is 41%, and that of the entire system including parasitic pump power, heat loss due to freeze protection, and heat loss from connecting piping is 34%. Annual average collector efficiency based on a net aperture area of 36 m2 is 61.5% according to the hourly simulation.

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.

scholarly journals METHODOLOGY OF THE PRIMARY DATA RECONSTRUCTION OF SINGLE PIPE HEATING SYSTEMS/VIENVAMZDŽIŲ ŠILDYMO SISTEMŲ PIRMINIŲ DUOMENŲ NUSTATYMO METODIKA

1999 ◽  
Vol 5 (5) ◽  
pp. 318-322
Author(s):  
Edvardas Tuomas ◽  
Saulius Neverbickas
Keyword(s):  
World War Ii ◽  
District Heating ◽  
Heating System ◽  
Heat Fluxes ◽  
Primary Data ◽  
Complex Coefficient ◽  
Heating Systems ◽  
Pipe System ◽  
Central Heating ◽  
Single Pipe

The majority of dwellings in Lithuania are situated in blocks of flats. The dwellings were built after World War II and they are heated by single pipe central heating systems, connected to district heating. The dwellers are not quite satisfied with such a heating system and try to improve it, but do that in a wrong way, by increasing the surface of radiators. Such means lead to violation of thermal regime and comfort conditions for other dwellers. There exists sometimes the necessity of reconstructing premises and together—the heating system. During the reconstruction the primary heat fluxes from radiators should be known, but very often such data are lost and only the size of radiators (number of sections) are known. To reconstruct the required primary data for single pipe systems is complicated because the temperatures of inlet and outlet water for radiators are unknown. In this article the methodology is proposed how to perform the calculations leading to the required data. The aim of calculations is the establishment of heat fluxes from each radiator connected to the riser. Heat flux from radiator can be calculated according the formula (1) but the complex coefficient is unknown. It could be found from formulae (2) but some magnitudes are unknown. According to the proposed methodology the values of unknown magnitudes are taken approximately and calculations are performed with iterations. In such a way the flow rate of water in riser is established from formula (3), which is the same for each radiator (the property of single pipe system). From formulas (3) and (4) an equation is produced (5), and is used for calculations of unknown temperatures. The equation (6) is used for calculation of heat fluxes from radiators. To carry out the above-mentioned calculations without computer practically is impossible due to many cycles of iteration. The programme was prepared to make easy all these calculations. The scheme of algorithm of programme is given in Fig 1. An example of calculation is given in this article. Calculations were fulfilled by newly created programme. The riser chosen for calculation is shown in Fig 2. The results of calculation are given in Table 1. The table shows that according to the proposed methodology the programme based on it can be used for reconstruction of primary data of single pipe heating systems successfully.

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