scholarly journals Generation of Monodispersed Spherical Thermosensitive Gels and Their Swelling and Shrinking Behaviors in Aqueous Polymeric Solutions

2020 ◽  
Vol 10 (6) ◽  
pp. 2016
Author(s):  
Raden Rinova Sisworo ◽  
Masato Hasegawa ◽  
Kousuke Nakashima ◽  
Yu Norimatsu ◽  
Yukio Tada
Keyword(s):  
Buoyancy Force ◽  
Gravitational Force ◽  
Negative Thermal Expansion ◽  
Heating System ◽  
Continuous Phase ◽  
Vertical Movements ◽  
Factors Affecting ◽  
Polymeric Solution ◽  
Gel Particles ◽  
Swelling And Shrinking

This study investigates the factors affecting the formation of monodispersed thermosensitive gels and the parameters influencing the movement of gel particles containing N-isopropyl acrylamide in an aqueous polymeric solution in an upper heating system. Monodispersed thermosensitive gels were generated, and their swelling and shrinking behaviors were observed. The results revealed that continuous-phase flow rate and kinematic viscosity were most influential on the size of the monodispersed thermosensitive gels, which exhibited swelling and shrinking at both low and high temperatures of the polymeric aqueous solution, respectively, and demonstrated negative thermal expansion. In a low-temperature solution, the buoyancy force acting on the gel particles exceeded the gravitational force, because of which the size of the gels increased and the gels to ascended. At higher temperatures, the gels shrank because the gravitational force outweighed the buoyancy force, causing the gels to descend. The gels with a larger diameter tended to have longer durations of vertical movements within the aqueous polymeric solution than the smaller-sized gels; moreover, equilibrium conditions were quickly achieved by the smaller gels.

Workpiece Movement in Centerless Grinding and Its Influence on Quality of the Ground Part

1988 ◽  
Vol 110 (2) ◽  
pp. 179-186 ◽  
Author(s):  
N. G. Subramanya Udupa ◽  
M. S. Shunmugam ◽  
V. Radhakrishnan
Keyword(s):  
Dynamic Instability ◽  
Vertical Movement ◽  
Experimental Investigations ◽  
Critical Factors ◽  
Vertical Movements ◽  
Factors Affecting ◽  
Centerless Grinding ◽  
Cylinder Liners ◽  
Ground Part

The grinding action and the rounding mechanism are highly complex in centerless grinding. The process geometry and the dynamic stability of the workpiece are critical factors affecting the quality of the ground parts. The workpiece, because of floating condition, has an inherent tendency to become unstable during grinding. This is particularly true in the case of hollow workpieces like bearing races, bushes, cylinder liners, etc. In this paper, an attempt has been made to investigate the dynamic instability of the workpiece and to identify its effects on the quality of ground parts in infeed grinding. The details of the experimental investigations carried out to measure the horizontal and vertical movements of the workpiece directly on the machine are included. Some measures to minimize the vertical movement of the workpiece and to improve the quality of the ground part are also discussed.

scholarly journals Analysis of Influencing Factors of Heat Load of Heating Power Station

2021 ◽  
Vol 252 ◽  
pp. 01042
Author(s):  
Yu Lu ◽  
Rui Li
Keyword(s):  
Influencing Factors ◽  
Heat Load ◽  
Load Forecasting ◽  
Heating System ◽  
Heating Power ◽  
Power Station ◽  
System Planning ◽  
Factors Affecting ◽  
Heating Load ◽  
Selection Of

Heating system load forecasting is very important in heating system planning and formulating heating plans. More accurate load forecasting can obtain greater economic and social benefits for the heating power station. The selection of influencing factors affecting heating load forecasting has a decisive effect on the accuracy of load forecasting. Based on the analysis of heat load of typical heating power station, this paper compares and analyses the influence of outdoor temperature, wind speed and load of previous days, etc. The main factors that should be considered in heating load forecasting are obtained.

Factors affecting focusing performance of continuous phase plate concentration

2012 ◽  
Vol 24 (7) ◽  
pp. 1741-1744
Author(s):  
张远航 Zhang Yuanhang ◽  
杨春林 Yang Chunlin ◽  
温圣林 Wen Shenglin ◽  
颜浩 Yan Hao ◽  
王健 Wang Jian ◽  
...  
Keyword(s):  
Continuous Phase ◽  
Phase Plate ◽  
Factors Affecting

scholarly journals Investigation of parameters affecting the optimum thermal insulation thickness for buildings in hot and cold climates

2020 ◽  
Vol 24 (5 Part A) ◽  
pp. 2891-2903
Author(s):  
Ahmet Canbolat ◽  
Ali Bademlioglu ◽  
Kenan Saka ◽  
Omer Kaynakli
Keyword(s):  
Cooling System ◽  
Heating System ◽  
Climatic Conditions ◽  
Graphical Form ◽  
Insulation Material ◽  
Factors Affecting ◽  
Heating And Cooling ◽  
Present Worth ◽  
Insulation Thickness ◽  
Optimum Insulation Thickness

This paper investigates the factors affecting the optimum insulation thickness and its pay-back period, such as heating and cooling energy requirements of building, lifetime, present worth factor, costs of insulation material and installation, costs of energy sources for heating and cooling, heating and cooling system efficiencies, and solar radiation. For this purpose, by considering two cities characterizing the hot and cold climatic conditions, the optimum insulation thickness and its pay-back period have been calculated and a detailed parametric analysis has been carried out. To achieve practical results, the ranges of the parameters considered in the study include the values typically reported in the literature. The variations in the optimum insulation thickness and the pay-back period with all parameters are presented in graphical form. Finally, order of importance and contribution ratios of the examined parameters on the optimum insulation thickness are determined with the help of Taguchi method. It is found that heating degree-days is the most efficient parameter on the optimum insulation thickness with an impact ratio of 27.33% of the total effect while the least efficient parameter is the efficiency of heating system with an impact ratio of 3.21%.

AIR INFILTRATION AND ROOM HEAT LOSS THROUGH WINDOW OPENINGS

2016 ◽  
Vol 6 (3) ◽  
pp. 10-16 ◽  
Author(s):  
Vladimir I. VESNIN
Keyword(s):  
Heat Loss ◽  
Natural Ventilation ◽  
Heating System ◽  
Hydraulic Loss ◽  
Cooling Process ◽  
Transfer Resistance ◽  
Factors Affecting ◽  
Air Infiltration ◽  
Exchange Processes ◽  
Discontinuous Mode

The research of cooling processes of a building, when heating system is operating in discontinuous mode, is carried out. Factors affecting temperature decrease rate are analyzed. Influence of cold air infiltration on heat exchange processes is shown. Methods of aerodynamic calculations of natural ventilation are specified. Method of pressure determination in-building, taking into account infiltrative air hydraulic loss, is proposed. Cooling process with air infiltration is calculated. Infiltration increases clinograde by 0.4-1°C per hour. Existing materials of heat transfer resistance through fiberglass windows constructions are compiled. Practical proposals for reducing of air infiltration and heat loss through openings are made.

Simulation of Nanofluid Heat Transfer Enhancement With LBM

2012 ◽  
Author(s):  
Yali Guo ◽  
Daoyang Qin ◽  
Shengqiang Shen ◽  
Hehan Xu ◽  
Yong Yang ◽  
...  
Keyword(s):  
Heat Transfer ◽  
Temperature Field ◽  
Buoyancy Force ◽  
Gravitational Force ◽  
Pure Liquid ◽  
Two Dimensional ◽  
Transfer Enhancement ◽  
Internal Forces ◽  
Simulation Results ◽  
Multi Phase

Heat transfer and fluid flow in a two-dimensional enclosure filled with nanofluids is investigated using multi-phase LBM, where the influences of external and internal forces, for example, the Bromnian force, gravitational force, drag force, buoyancy force and the interactions among particles on the molecular levels, are considered. The velocity field and the temperature field are obtained at different nanoparticles volume fractions, different buoyancy parameters. The simulation results show that nanofluids could enhance the heat transfer compared to pure liquid.

METHOD FOR STUDYING THE INFLUENCE OF THERMAL INERTIA ON THE ROOM TEMPERATURE

2021 ◽  
Vol 7 (2) ◽  
pp. 188-205
Author(s):  
Artur R. ROMAZANOV ◽  
Irina G. ZAKHAROVA
Keyword(s):  
Data Analysis ◽  
Thermal Energy ◽  
Thermal Regime ◽  
Thermal Inertia ◽  
Weather Conditions ◽  
Heating System ◽  
Lag Time ◽  
Classification Model ◽  
Time Interval ◽  
Factors Affecting

The efficiency of using thermal energy that is received from the central heating system to supply a building (a complex of interconnected rooms) is determined by the completeness of information available on the factors that affect the thermal regime. This article presents an approach that allows evaluating the significance for thermal management of such complex parameters as thermal inertia of a room and features of its use. The proposed methodology is based on the analysis of the dynamics of temperature changes in rooms, considering the standard characteristics that determine heat exchange, meteorological conditions, and the presence of people. The degree of the thermal inertia influence on a room is determined on the lag time, which is the time interval between a significant change in weather conditions or the supply of thermal energy and a change in the air temperature in the room. The initial data included the values of the temperature of the air and heating elements, that were obtained from the sensors located in a university building. The observation was conducted between 1 March and 19 April 2020 (measurement frequency — 10 minutes). The collected data consist of measurements gathered during room usage in different modes. Additionally, the presence of periods of complete shutdown of the heating system also affected the respective data. The module of the intelligent monitoring system for the thermal regime of the building was developed to perform data analysis. The module was implemented as a pipeline that sequentially performs the following operations: filtering and cleaning data; aggregation for specified periods; determination of the delay time. The results of the data analysis show the possibility of selecting groups of rooms that react to significant changes in external conditions and heating mode with a remarkable lag time. This confirms the importance of considering the thermal inertia for efficient heating control (intermittent operation). The results allow concluding that it is possible to build a classification model based on the thermal inertia parameter. These models will help in determining the most significant factors affecting the thermal regime of the room. In its turn, it allows producing recommendations for making decisions on heat supply management.

scholarly journals Study of Vertical Movements of the European Crust Using Tide Gauge and Gnss Observations

2015 ◽  
Vol 97 (1) ◽  
pp. 112-131 ◽  
Author(s):  
Kornyliy Tretyak ◽  
Solomiya Dosyn
Keyword(s):  
Tide Gauge ◽  
Tide Gauge Data ◽  
Vertical Movements ◽  
Factors Affecting ◽  
Level Change ◽  
The Earth ◽  
Gauge Data ◽  
Gnss Observations

AbstractThis research is devoted to the study of vertical movements of the European crust on the basis of two independent methods, namely tide gauge and GNSS observations results. The description and classification of factors affecting sea level change has been made. The precision with which the movement of the earth's crust according to the results of tide gauge observations can be explored has been calculated . A methodology to identify the duration of tide gauge observations required for studies of vertical movements of the earth 's crust has been presented. Approximation of tide gauge time series with the help of Fourier series has been implemented, the need for long-term observations in certain areas has been explained. The diagram of the velocities of the vertical movements of the European crust on the basis of the tide gauge data and GNSS observations has been built and the anomalous areas where the observations do not coincide have been identified.

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