The community heating network’s thermal condition assessment

Heat losses at the heating network’s distribution pipelines were identified for Karkivcommunity. Heat losses’ calculation is performed in view of the underground pipelines’ installationin non-accessible ducts. The heating system water temperature is accepted in line with the heatingnetwork temperature chart and according to the design outdoor temperature value for heatingpurposes. Specific heat losses in the network section’ pipelines are accepted at the level of standardvalues for the specified network laying method. The water flow rate at the heat pipeline sections isdefined as per the design heat loads from the buildings connected to the heat supply network. Theheat pipeline segment with uniform diameter is accepted as the rated section. The soil temperatureat the heat pipeline axis laying depth is accepted as 5°C. The heat losses at the structural networkelements are considered by 1.15 coefficient. The calculations are performed in view of the heatingsystem water flow rate and temperate changes along the heat pipeline length. While analyzing thethermal condition of the return pipelines of the community heating network, the changes in the heatcontent of the heating system water flow in the main direction pipeline during mixing with the waterflow from the branches of the main direction line are taken into account. Considering the averagetemperature of the coldest five days consecutively, the total energy loss in heating pipeline for a groupof buildings in Kharkov region are equivalent to 180.8kW.In view of the ambient air temperature changing over the heating period for Kharkiv cityclimate conditions and the current schedule for quality heat energy supply to the consumers controlthe annual heat losses in the community heating network pipelines were calculated. The soil temperature change at the heat pipeline installation depth during the heating period was notconsidered.Heat losses in the microdistrict network for the year are 2184 GJ. The data obtained can beused to compare options when developing a strategy for reforming the microdistrict heat supplysystem.

Prototype System Water Level Reservoir untuk Pengendalian Kelebihan Air dengan Mikrokontroller Arduino Uno R3

PDAM Loa Kulu Branch still uses sticks or poles as an indicator of the water level in the reservoir. Reservoir is a place to store clean water production from PDAM, the weakness of using sticks or poles is when the operator does not monitor continuously causing air loss when production becomes large. The goal of the study was to design a water-level prototype to control excess water in the reservoir. The method used is a prototype with the stage of gathering information through interviewing PDAM staff, creating and repairing prototypes and testing prototypes. The test used hardware consisting of Arduino uno r3, ultrasonic sensor hc-sr04, flowmeter sensor yf-s201, 16 x 2 lcd, relay module, buzzer, solenoid valve 12 V_dc, pump 12 V_dc and display measurement results in the visual studio application 2019. Our findings are that the length of reservoir charging with an average input discharge of 3.6 liters / minute is 2.93 minutes. As for the length of emptying the reservoir with an average output discharge of 1.06 liters / minute is 12.10 minutes. The conclusion of this study is that the system can monitor the water level inside the reservoir automatically and know the time needed for the feeling and emptying process of the reservoir.

Prototype System Water Level Reservoir untuk Pengendalian Kelebihan Air dengan Mikrokontroller Arduino Uno R3

PDAM Loa Kulu Branch still uses sticks or poles as an indicator of the water level in the reservoir. Reservoir is a place to store clean water production from PDAM, the weakness of using sticks or poles is when the operator does not monitor continuously causing air loss when production becomes large. The goal of the study was to design a water-level prototype to control excess water in the reservoir. The method used is a prototype with the stage of gathering information through interviewing PDAM staff, creating and repairing prototypes and testing prototypes. The test used hardware consisting of Arduino uno r3, ultrasonic sensor hc-sr04, flowmeter sensor yf-s201, 16 x 2 lcd, relay module, buzzer, solenoid valve 12 V_dc, pump 12 V_dc and display measurement results in the visual studio application 2019. Our findings are that the length of reservoir charging with an average input discharge of 3.6 liters / minute is 2.93 minutes. As for the length of emptying the reservoir with an average output discharge of 1.06 liters / minute is 12.10 minutes. The conclusion of this study is that the system can monitor the water level inside the reservoir automatically and know the time needed for the feeling and emptying process of the reservoir.

Policy Options of Over-Pumping Control in the NCP

Starting in the 1990s, China has been issuing regulations and policy rules related to groundwater management and pumping control on both national and provincial levels. These policies include the requirement of permits for well drilling, a well spacing policy, pumping quota management, water resources fee collection, setting of irrigation water prices, a water rights system, water markets, and more.

Dynamics of microelements (B, Al) in the water samples from the Prut river during the 2020 year

The purpose of this research was to study the dynamics of microelement content, the correlation between the main forms of migration of microelements (B, Al) - dissolved and suspended forms, except colloidal, and to study their seasonal variation. The main form of migration of the metalloid B in the waters of the Prut river is the dissolved one, while the migration form of Al is the suspensions. In this research, the content of the mentioned microelements was investigated in the water samples collected from the Prut River in 2020 (winter, spring, summer, and autumn) from 7 collection points. The microelements were determined using atomic absorption spectrophotometry (Perkin-Elmer AAnalist 400 atomic absorption spectrophotometer). The importance of determining trace elements in natural waters is determined by a number of issues, including the need to monitor the environment and assess environmental risks and assess their influence on living systems. The results of studying these forms of migration (dissolved and suspended) allow us a fuller understanding of their role in the migration of microelements in aquatic ecosystems in the system "water-suspensions-underwater deposits-hydrobionts".

Method Development for Leachable Furfural Determination in Wood-Based Panels by HPLC-Uv System

Analytical method has been developed and validated to determine free or leachable furfural concentration in wood-based panels. Particleboards obtained from birch wood and suberinic acids binder were chosen as a reference material. Two methods and two solvents were tested. Acetone extracts of the samples were analyzed with gas chromatography (GC) flame ionization detector system. Water extracts were analyzed with high-performance liquid chromatography-ultraviolet spectroscopy (HPLC-UV) system. After the GC data in acetone extracts furfural concentration was below method limit of detection. HPLC-UV data showed that in water extracts furfural concentration was possible to determine. It was concluded that HPLC-UV is suitable and fast method for furfural determination in wood-based panels water extracts.

Evaluation of melt-water premixture formation due to Rayleigh-Taylor instabilities

A linear analysis of the stability of the three-layer stratified hydrodynamic system “water (top) – steam – melt (bottom)” has been performed. Kinematic and dynamic conditions on the “water – steam” and “steam – melt” interfaces are formulated, and on their basis a dispersion equation is obtained that relates the circular frequency of perturbations to the wavenumber. Analysis of this equation made it possible to determine the region of instability of this system and to find the wavenumber of the most fastly growing harmonics. The results obtained were used to estimate the size of bubbles formed at the interface between steam and water due to the development of the Rayleigh-Taylor instability. The obtained theoretical results are consistent with experimental observations in such systems. The heights of the melt splashes into water due to the collapse of the formed steam bubble were estimated. The obtained estimations demonstrate possibilities of the formation of melt-water mixture region during the spreading of the melt under a water layer, in which a strong steam explosion can occur.