bluuebunny/crossref_metadata_2025 huggingface dataset:
Flame stretching by electric field
Authors: Tupikin A V , Zamashchikov V V
Published: December 2019

The paper considers the issues related to the study of the mechanisms of controlling the combustion of hydrocarbon fuels by electric fields. It is shown that influence of weak electric field on combustion in laminar mode leads to a change in the degree of flame stretching (Karlovitz number). For the Bunsen flame and reversed flame, estimates of changes in values of the degree of flame stretching when imposing an external constant electric field on flame are made.
Study of the possibility of steady horizontal flight of the dual aircraft platform with the wind shear
Authors: Akimov A M , Polivanov P A
Published: December 2019

In the first part of paper accurate and approximate solution for the equation of motion of steady horizontal flight for dual-aircraft platform (DAP) was given. The two gliders (sailplanes) fly at different heights and connected by a tether. To perform a horizontal flight only the effect of wind shear is used. Minimum of platform velocity to cross wind shear ratio was founded. In the second part of paper overview airflow for troposphere and stratosphere of Earth was given. Wind velocity profile was investigated for some random places. Opportunity of flight without engine was approved. However it is possible at specific conditional only.
Flow features in a hypersonic module with a compact cross-section
Authors: Akinin S A , Starov A V
Published: December 2019

A model of a hypersonic air intake based on the principle of compression along the directions of the captured jet converging in space is studied. Such an air intake allows a high compression ratio and a compact section of the internal channel, which simplifies the heat protection of the air intake and the combustion chamber. Experimental studies were carried out in a pulsed wind tunnel IT-302M for Mach number M = 6 - 8 in the range of angles of attack from 0° to 8°. Numerical simulation has been performed based on solving the full averaged Navier-Stokes equations, supplemented k-w turbulence model. The pressure distributions on the compression surfaces and in the air intake channel are obtained, the coefficients of the total pressure recovery and flow rate, the Mach number in the throat of the air intake are determined. The features of the flow structure for three variants of the air intake in the area of external compression are established: with side walls, side walls with slots and without side walls. The influence of the boundary layer bleed and lateral spreading on the launch and integral characteristics of a hypersonic air intake with a compact cross-section of the inner channel is determined. Satisfactory agreement between the calculated and experimental data is shown.
Influence of surface sublimation on boundary layer stability at high Mach number
Authors: Gaponov S A , Semenov A N , Smorodsky B V
Published: December 2019

Results of theoretical investigation of the linear stability properties of Mach 6 boundary layer on a flat-plate with sublimation coating are presented. Naphthalene (C
10
H
8) was chosen as a substance for such a coating. This is an organic compound capable to pure sublimation (phase transition from the solid state directly to gas, bypassing the melting stage) at moderate temperatures. Calculations performed on the basis of binary-mixture boundary-layer equations in the approximation of local self-similarity revealed that with increasing flow stagnation temperature the adiabatic surface temperature also increases that causes growth of mass flow rate of naphthalene evaporation. This leads to an increase in the density of the binary mixture (air and sublimation vapors) near the wall. The performed linear stability computations show that such a modification of the boundary layer profiles causes a reduction in the local linear amplification rates of perturbations of the first mode, while disturbances of the second mode are destabilized by the surface sublimation.
Effect of stationary longitudinal structures on the growth of Tollmin-Schlichting waves
Authors: Gaponov S A , Terehkova N M
Published: December 2019

The paper considers the possibility of increasing of the nonstationary wave (similar to Tollmin-Schlichting (T-S) wave) growth by striped stationary structures of eigen-problem of stability of the supersonic boundary layer stability. The problem is solved within the framework of three-wave resonance interaction in local-parallel approximation. In this work the pumping wave is the stationary almost striped structures. Studies have shown that even in a stable area under the influence of longitudinal structures there is an increase of T-S waves. At sufficiently high amplitudes of stationary perturbations their effect on T-W waves is noticeable even in unstable area.
The influence of dual stream jet nozzle internal parts on the three-dimensional flow structure in a supersonic jet
Authors: Kiselev N P , Zapryagaev V I , Kundasev S G
Published: December 2019

The work is devoted to the experimental study of a high-speed jet exhausting from a model dual stream jet nozzle, performed using non-contact (shadow visualization) and probe (total-pressure pneumatic receiver) methods for measuring gasdynamic quantities. Azimuthal non-uniformity of the pressure distribution, whose value in the external duct is much higher than that in the internal duct, is revealed. The cause for the formation of the spatial flow structure is related to the supporting pylons inside the nozzle contour and to the occurrence of a transonic flow regime in the external duct.
Effect of a uncertainties of flow parameters on the separation zone at supersonic speeds
Authors: Kutepova A I , Polivanov P A , Sidorenko A A
Published: December 2019

The CFD calculations were performed basing on RANS approach with the Menter transition model [1]. The shock wave / boundary layer interaction (SWBLI) developed on a flat plate was considered. The oblique incident shock wave was generated by a wedge which was placed over the plate. The sensitivity of the separation zone to various inflow and geometrics parameters was studied. Verification of the calculations was carried out on the basis of experiments performed in the T-325 wind tunnel [2] for an angle of attack of wedge β = 4°.
Investigation of jets mixing in the channel of the hypersonic rocket-ramjet engine model
Authors: Lokotko A V
Published: December 2019

A technique of investigating jet mixing in the channel of a rocket-ramjet engine model in the conditions of an external supersonic airflow is proposed. Rocket exhaust jets are modeled with heated high-pressure air. Numerical computation of the mixing ratio (V. I. Kopchenov, Central Institute of Aviation Motors (CIAM)) yielded satisfactory qualitative agreement with the experimental results.
Influence of individual roughnesses nozzle edge on the length of the supersonic section of an underexpanded microjet
Authors: Mironov S G , Aniskin V M
Published: December 2019

The paper presents the results of the experimental investigation of the influence of a small group of roughnesses uniformly located on the edge of the convergent nozzle on the length of the supersonic core of an underexpanded air microjet. The tests are carried out on the low-pressure test bench with the aid of the Pitot tube. The set of nozzles with the diameter of 2 mm, with the smooth output edge and the edge of the similar shape roughnesses (from 2 to 4) is used. The underexpanded microjets flowing out from the nozzles of the diameter 10.6; 16.1; 21.4, and 34.8 μm are simulated by the outflow Reynolds number. It is shown that the presence of roughnesses can reduce essentially the supersonic section length and eliminate the previously found effect of microjet “relaminarization”, however the reduction value dubiously depends on the amount of the roughnesses on the nozzle edge.
Stability of the laminar boundary layer on the surface of the Mach-6 contoured nozzle
Authors: Morozov S O , Shiplyuk A N
Published: December 2019

The stability of the laminar boundary layer on the surface of the Mach 6 contoured nozzle designed for short-duration wind tunnel Transit-M is investigated. The numerical simulation of the laminar flow inside the nozzle is performed using Ansys Fluent software. The obtained boundary layers profiles on the nozzle surface are used to calculate the growth rate of the first and second Mack mode and Görtler vortices in the framework of the linear stability theory. It has been shown that, for the Mach 6 nozzle, the Görtler vortices grow most rapidly, the first Mack mode grows slower, and the second mode is insignificant.
Gas-dynamic factors controlling the level of the sonic boom generated by two bodies in a supersonic flow
Authors: Moskvichev D Yu , Potapkin A V
Published: December 2019

The results of calculation of the sonic boom generated in a supersonic air flow by two bodies (disk and slender body of revolution) are presented. The bodies are arranged one behind the other. The slender body is aerodynamically shaded by the disk. The free-stream Mach number is 2. The calculations are performed by a combined “phantom bodies” method. The sonic boom level can be reduced by more than 12% via the disk position and size changing, as compared to the sonic boom generated by the slender body. the gas-dynamic factors affecting the sonic boom level are described on the base of the calculation results.
Determination of the heat transfer coefficient during the leakage of a subsonic axisymmetric air mini jet onto a plate
Authors: Mukhin K A , Aniskin V M , Maslov N A
Published: December 2019

In the present article, the heat transfer coefficient was determined experimentally when a subsonic jet flows onto a plate. The jet escaped from axisymmetric nozzles with a diameter of d = 290, 540, and 980 μm. The experiments were carried out at the speeds of V = 5, 20, 40, 60, 80 and 100 m/s in the Reynolds numbers range of 100 – 7000. The Nusselt number distribution was obtained for different distances between the nozzle and cooled surface.
The controlled periodic impact on the longitudinal vortex in the boundary layer at Mach 2
Authors: Piterimova M V , Kosinov A D , Panina A V , Semionov N V , Ermolaev Yu G , Yatskikh A A
Published: December 2019

Experimental data on the development of controlled disturbances in the boundary layer with a longitudinal vortex are analysed. It is found experimentally that the mean flow nonuniformity can vary from 0.7 to 0.9 V in terms of the CTA mean voltage or 30–40% in ρU. Such flow nonuniformity complicates the estimation of the wave spectra, where normalization on the mean voltage of the anemometer is required. The applicability of the standard processing procedure is investigated. Comparative analysis of the data shows that both normalization types considered in the work can be applicable. However, in the case of flow nonuniformity in the transverse direction, it is preferable to use the normalization on the median value over the mean voltage spanwise distribution.
Studying of the resonator depth influence on amplitude-frequency characteristics operating flow in the two-channel system
Authors: Primakov A V , Zhilin A A
Published: December 2019

This paper is devoted to an experimental study of the characteristics of the operating flow in a two-channel system of an acoustic-convective dryer (ACD), developed at the Institute of Theoretical and Applied Mechanics (ITAM) SB RAS. A parametric study of cylindrical resonator depth and pressure in settling chamber influence on amplitude-frequency characteristics (AFC) of the formed flow is carried out. The influence of pressure in settling chamber and geometry of resonant cavity on AFC are considered. A tendency toward a decrease in Hartmann effect existence region with a decrease in cavity depth was found. A satisfactory agreement was obtained between the frequencies registered in the experiments and calculated using the Helmholtz formula for the natural frequency of resonant cavity.
Experimental study of the laminar-turbulent transition on models of wings with subsonic and supersonic leading edge at M = 2
Authors: Semionov N V , Yermolaev Yu G , Kosinov A D , Kocharin V L , Panina A V , Semenov A N , Shipul S A , Yatskikh A A
Published: December 2019

The paper is devoted to an experimental study of laminar-turbulent transition in supersonic boundary layers on swept wings at Mach 2. The experiments were fulfilled in the low nose supersonic wind tunnel T-325 of Khristianovich Institute of Theoretical and Applied Mechanics on the models with supersonic or subsonic leading edges. The transition location was determined using a constant temperature hot-wire anemometer. while experiments for the case of a supersonic leading edge are a continuation of previous studies, then for the case of a subsonic leading edge, the first data have been obtained that show the possibility of carrying out studies on the development of unstable perturbations. It was obtained that transition take place parallel to the leading edge for both models. The destabilizing effect of the surface curvature of the model on the position of the laminar-turbulent transition for the case of a supersonic leading edge was confirmed. This experimental data is the room for further investigation.
On determining the vortex core center in wing wake at M = 2
Authors: Shevchenko A M , Shmakov A S , Kulikov V V
Published: December 2019

The paper presents the processing of the results of numerical simulation of the vortex flow in the wing wake, the purpose of which is to search for the vortex core center. It is based on the results of numerical simulation of the vortex flow in the wake behind of the rectangular wing, performed at the Keldysh Institute of Applied Mathematics RAS. The center of the vortex core was determined in several ways: by the minima of the total and static pressure, the axial Mach number, mass flow rate, the maximum of axial vorticity, and as the center of mass of the axial vorticity distribution. A comparison of the results of determining the position of the vortex core center showed good quantitative agreement. As a result dependencies of vortex core center coordinates on longitudinal coordinate were obtained.
Experimental research of the supersonic core length in the supersonic jet flowing from the rectangular micro-nozzles with different aspect ratios
Authors: Timofeev I V , Aniskin V M
Published: December 2019

The supersonic core length of the air microjets flowing from rectangular micro-nozzles with different aspect ratios has been experimentally studied. The height and width of the nozzles varied from 119 to 135 μm and from 927 to 2185 μm, respectively.
“N-wave” propagation in supersonic flow at flow past the flat plate with sharp edge
Authors: Yermolaev Yu G , Chudinova Yu I , Kosinov A D , Semionov N V
Published: December 2019

The paper discusses the results of an experimental study of the propagation of the “N-wave” in a supersonic flow and its interaction with the bow shock wave, which is formed at flowing around a flat plate with a sharp leading edge. It was found that the “N-wave” does not change its direction when interacting with the bow shock. However, this interaction leads to a reduction of the “N-wave”. Estimates of the propagation angles of the “N-wave” in a supersonic flow are also obtained.
Simulation of linearly extended streamer with planar geometry at atmospheric pressure
Authors: Alexandrov A L , Schweigert I V , Zakrevsky Dm E
Published: December 2019

The cold atmospheric plasma (CAP) jet is used in different applications, for example, in medicine. Typical plasma devices have the cylindrical symmetry. In this work, the new type of device with planar geometry of CAP jet is considered. The initiation of two-dimensional streamer and its propagation from linearly extended electrode to the treated surface is considered with the help of 2D fluid discharge model. Differently to the case of an axially symmetric plasma jet, the streamer head has a plate shape and the ionization wave propagates with considerably larger velocity.
Starting flow in an impulse wind tunnel with a throttled prechamber
Authors: Gounko Yu P , Kavun I N
Published: December 2019

The unsteady axisymmetric flow forming in the process of starting an impulse wind tunnel equipped with a throttled prechamber was numerically simulated. A regime with the operating flow Mach number M = 8 was under consideration. Numerical simulation on the basis of Reynolds-averaged Navier–Stokes code and the k-ω SST turbulence model was performed. The starting process was simulated as a sudden rupture of a diaphragm separating the prechamber volume with high pressure and temperature from low pressure part of the facility including a nozzle, an operating section and an exhaust vacuum tank.. The diaphragm rupture initiates a gasdynamic process associated with the Riemann problem when the primary shock wave arises which moves through the nozzle to the operating section. Computed data show another “inverse” shock wave emerging in the nozzle. A starting “shock-wave package” forms between these shock waves, it includes a flow portion of high temperature and pressure. The specificity is discussed of identified the characteristics and flow patterns forming during the process of moving the shock-wave package.
Direct Monte Carlo simulation of development of the Richtmyer-Meshkov instability on the Ar/He interface
Authors: Kashkovsky A V , Kudryavtsev A N , Shershnev A A
Published: December 2019

The Richtmyer-Meshkov instability developing on the interface between helium and argon gases hit by a propagating shock wave is simulated numerically. In contrast with conventional approach based on the Navier-Stokes equations, the simulation in the current paper is performed on the molecular level using the Direct Simulation Monte Carlo method. The data averaging over short time periods is employed to decrease statistical scattering. The instability development is successfully reproduced with relatively moderate computer resources used. The time evolution of the transmitted shock wave and contact surface velocities are retrieved from numerical data as well as the instability growth rates.
Modeling flows of underexpanded jets in a slot space
Authors: Kiselev S P , Kiselev V P , Zaikovskii V N
Published: December 2019

In the present paper, we report on the results of a study of supersonic gas flows in a slot space. It is shown that the structure of the ejected jet exhausting into a slot ambient space substantially depends on the friction force. The latter force leads to a substantial change of the supersonic jet, which acquires, instead of a barrel-shaped, a fan-shaped form. The results of numerical simulation are consistent with experimental data.
Numerical simulation of sonic boom near-field flow over 69-degree delta wing body
Authors: Kiseleva T , Lukeshevich S
Published: December 2019

Fast and accurate prediction of sonic boom intensity is important in performing design and optimization studies of a supersonic aircraft. The paper presents the computational mesh generation technique for sonic boom prediction in the near field of complex geometry body. Studies are done on a 69-degree delta wing body model used for testing various prediction techniques in the framework of the AIAA Sonic Boom Prediction Workshops.
Linear stability of supersonic boundary layer over a cooled porous surface
Authors: Kudryavtsev Alexey , Khotyanovsky Dmitry
Published: December 2019

The linear stability of the boundary layer at high supersonic Mach numbers on a flat plate with a cooled porous surface is studied. As is well known, at high supersonic speeds, both vortex disturbances of the first mode and acoustic disturbances of the second mode are unstable. The more unstable disturbances of the second mode can be stabilized using sound-absorbing porous coatings. At the same time, such coatings have a destabilizing effect on the disturbances of the first mode. Surface cooling is one of the factors potentially capable of preventing such a destabilization. Based on this assumption, in the present work, the linear theory of stability is used to consider the combined effect of a sound-absorbing coating and surface cooling.
The influence of nozzle geometry on the gas-dynamic structure of the supersonic nonisobaric jet
Authors: Kundasev S G , Zapryagaev V I , Kiselev N P , Rybak S P
Published: December 2019

The paper presents the investigation results of the flow structure of cold supersonic jets flowing out of model nozzles with a Mach number on the exit Ma
= 3.5: an axisymmetric nozzle, a nozzle with a rectangular critical section, a beveled nozzle with a rectangular critical section. Flow schlieren images and transverse measured total pressure profiles in the flow are presented. The influence of the critical section shape and the beveled exit section on the shock-wave structure of the flow is described.
Essay of thermodynamic description and optimization of Ranque effect
Authors: Latypov A F
Published: December 2019

This paper presents a thermodynamic description of Ranque effect. Including expansion and compression works into energy exchange provides a rational explanation of the observed effect. These works are performed by small portions of gas in polytropic processes. Rotational motion of the gas and presence of non-reversibility in the processes of expansion and compression are responsible for energy separation. A mathematical model with the use of the conservation laws and the polytropic expansion process was created. Optimization calculations for various values of the polytropic efficiency coefficient and the Mach number of hot gas outflow were performed. It has been obtained that the optimal relative values of exit-section area and the Mach number of inflowing high-pressure gas are invariant with respect to the values of the parameters mentioned above. Using this result, a practical model for optimizing operation process was elaborated. The efficiency coefficient of expansion work is determined during the optimization process. Using this result a practical technique of operational process has been developed.
Numerical simulation of a two-component gas flow near a highway
Authors: Lavruk and S A , Valger S A
Published: December 2019

Numerical simulation of the air flow near a highway was carried out taking into account injection of ethane through a system of low sources. Numerical model is based on full physical and mathematical models of continuum media and takes into account the phenomena of turbulent mixing of gas components in the surface boundary layer. Based on the calculation results, the fields of velocity distribution, turbulent parameters and impurity concentrations in characteristic sections near the road are obtained.
Numerical solution of the Vlasov-Poisson equations using a semi-Lagrangian WENO scheme implemented on GPU
Authors: Malkov E A , Poleshkin S O , Shershnev A A , Kudryavtsev A N
Published: December 2019

A numerical method for solving the Vlasov–Poisson equations using a high-order semi-Lagrange conservative WENO scheme is developed. The Vlasov–Poisson equations govern evolution of the collisionless self-interacting medium and are widely used in plasma physics and astrophysics, in particular for modeling dynamics of galactic systems. The method is implemented for computations on Graphical Processing Units (GPUs). The GPU code is validated using an exact unsteady analytical solution describing nonlinear oscillations of a plane self-gravitating layer. The comparison with numerical results obtained with the serial CPU code show a significant, up to 50 times, speed-up of the computations.
Study of the flow structure in boundary layer bleed channel at the hypersonic speed of external flow
Authors: Obodovskaia E A , Korotaeva TA , Goldfeld M A
Published: December 2019

The paper presents the study of the flow structure in a boundary layer bleed channel and calculation of the mass flow rate under the conditions of thick boundary layer incoming. The flow at Mach numbers of M = 3, 4, 6 and angle of attack 6° has been considered. In the framework of the problem, the Reynolds-averaged Navier-Stokes equations added with the k–ω SST turbulence model have been solved. Numerical simulation of the flow in the channel has been carried out using the Roe implicit scheme of the second order of accuracy. Pressure and temperature profiles at the outlet boundary obtained at the simulation of the flow around the inlet forebody have been used to specify the inlet boundary conditions for simulation of the flow through the boundary layer bleed hole. The pressure distribution obtained at numerical simulation of a flow in the boundary layer bleed channel has shown that there is a large high-pressure area caused by the presence of so-called “barrier shock” near the channel back wall. Thus here is a supercritical pressure drop which ensures a sonic flow in the bleed hole. This conclusion has been confirmed by the experimental data obtained for small supersonic speeds. Calculation of the mass-flow rate through exit cross-section of the cylindrical bleed channel has shown that the mass flow rate coefficient decreases 2.5 – 3 times with the Mach number increasing from 3 to 6. The mass flow coefficient also decreases by about 10% due to the change of conditions in the 3D flow before the bleed hole with the moving off from the symmetry plane.
Comparison of modern implementations of the direct simulation Monte Carlo method
Authors: Shugalevskaia N V , Shevyrin A A , Bondar Ye A
Published: December 2019

In this work, collisional schemes of the direct simulation Monte Carlo (DSMC) method are compared. The sensitivity of the schemes to the number of simulated particles is investigated. The original No-Time-Counter (NTC) scheme, proposed by G.A. Bird, its modification NTC-2007 and majorant collision frequency (MCF) scheme, proposed by M. S. Ivanov and S.V. Rogasinsky are considered. For the high-speed Couette flow with parameters corresponding to a near-continuum regime (speed ratio S is equal to 10, Knudsen number Kn is equal to 0.01) the convergence of shear stress component is analysed. Calculations with different total number of the simulated particles (in the range from 500 to 106) were performed. It was shown, that the deviation of NTC-2007 scheme from the reference solution is about four times larger as compared to the MCF scheme. The original NTC scheme exhibits much higher sensitivity to the number of simulated particles.
Simulation of the transition to turbulence in the boundary layer on complex-shaped bodies at an angle of attack
Authors: Sidorenko A A , Boiko A V , Demyanko K V , Kirilovskiy S V , Nechepurenko Yu M , Poplavskaya T V
Published: December 2019

The paper deals with the numerical simulation of the laminar-turbulent transition as the gas flow moves at a nacelle at transonic speeds. The laminar-turbulent transition position in the 3D boundary layer of the nacelle is found with the aid of the laminar-turbulent transition module based on the e
N
-method which involves the data of the numerical simulation of the laminar flow at the model with the gas-dynamic software package ANSYS Fluent. Performance of this module is demonstrated as the laminar-turbulent transition, caused by the Tollmien-Schlichting wave and crossflow instabilities, takes place. It is shown that the Tollmien-Schlichting wave instability is the dominating mechanism of the laminar-turbulent transition on the nacelle up to the angle of attack of 7°.
Historical precipitation data in Sumatra and Kalimantan from 1879 to 1900, by using Dutch colonial materials
Authors: Kajita R
Published: December 2019

Indonesia suffers from serious fire and haze problems occurring in the peatland areas of Sumatra and Kalimantan. Haze has become an international issue in Southeast Asia, and Indonesia must now implement better prevention management for this severe crisis. To understand the meteorological conditions in Indonesia, it is important to analyze the historical precipitation ranging back to the colonial days. This study focuses on historical precipitation data observed during the Dutch colonial era. The observation records from 1879-1900 were recorded in historical materials called “Regenwaarnemingen in Nederlandsch-Indie”. The records not only include Batavia, but also other observation stations in Indonesia. In this study, the historical precipitation data in Sumatra (Medan, Jambi, Bengkalis) and Kalimantan (Pontianak, Banjarmasin, Amuntai) were reconstructed. By using these reconstructed precipitation data, I analyzed the annual precipitation fluctuation and mean monthly precipitation at six stations. The colonial materials have not yet been examined enough in the meteorological research field, and their historical data contribute to Indonesia’s historical research and climatic problems.
Mitigating simultaneous returning home after large-scale earthquakes: changing tourists’ intentions to stay through public support
Authors: Sakai K , Toyoda Y , Kanegae H
Published: December 2019

The difficulty in returning home in response to an earthquake is a serious problem for tourists, and it is necessary to understand the obstacles involved. The purpose of this study is to highlight factors that affect tourists’ intentions to return home or stay at the site during an earthquake disaster. Questionnaires were administered to tourists in Himeji Castle, and 467 valid responses were obtained. This study analyzed data by decision tree analysis using the tourists’ personal attributes, sightseeing style, and the degree of public support as independent variables and tourists’ behavioral intention as the dependent variable. In the situations related to public support, it became clear that proximity to one’s residential area and available transportation to Himeji had an influence. Further, it was found that public support strongly affected the behavioral intentions of tourists who came from afar. The results confirm that public support, tourists’ attributes, and sightseeing style affect intentions.
Low energy measures for residential buildings in tropical regime
Authors: Utama N A , Hendriana D , Irawan R , Hadi M , Bahtiar T A , Suhedi F
Published: December 2019

Towards the direction of developing sustainable building in tropical regime in general and in Indonesia in particular, facing multiple dilemmas, one of the dilemmas starting from the issue of the core variables in the green building which is low-energy buildings. By definition the main target for low energy building is the target for self-sustaining its energy supply while improving its efficiency. The issue of low energy building, in recent years, gained attention and moved towards a large-scale introduction in the residential sector. During this process, international criteria for energy use in buildings have become stricter, whilst the national standard for low energy building have not move forward only Jakarta municipality and Bandung municipality have developed its strategic regulation to achieve those targets. With a primary focus on landed house both for semidetached and detached houses, this study analyses how the measures the low-energy buildings which may further developed to reduce the energy use in the residential sector. The main attention is on the designing the façade, wind flow and local material performances. A thermal and fluid dynamics approach is applied, which here means that the concept of low-energy buildings is investigated from two main perspectives, namely thermal comfort with low energy uses by means of optimization for natural cooling. The thesis thus encompasses methods from both engineering approaches the studied areas through design, assessments and simulations. The thesis reveals how an increased process integration of the building’s energy system can improve the thermal comfort in low-energy buildings. Moreover, local climate data was use, local material was collected – to study how the heat influences can be predicted in a low-energy building in the Bandung climate. The thesis further focuses on the low-energy building as an element in our society.
The implementation of sustainable community-based environmental sanitation development policy (SLBM) in Tebo Regency
Authors: Hidayat B , Ophiyandri T , Tudi A
Published: December 2019

As it is a very necessary in daily life, the problems of sanitation are categorized as very basic problems in health sector. However, the pollution process cause of sanitation takes very long time; therefore, many people tend to ignore the dangerous posed to their health. Geographically, the residents in Tebo Regency are mostly located onthe riverbank, with inadequate sanitation facilities. Some of these sanitation facilities were built through the SLBM program, but they do not work optimally. This research was conducted to determine the factors of un-optimal SLBM program and to manage the future strategies for better SLBM. This study used a qualitative descriptive approach. The data were collectedusing survey methods, questionnaires, and interviews communities and local governments. The results showed that the implementation of the SLBM Sustainable Development Policy in TeboRegency was not optimal yet, due to several factors, including: lack of training / guidance, non-functioning CBOs, lack of trigger for healthy lifestyle, lack of socialization, lack of supporting facilities, inconsistent standards, lack of synergy between stakeholders, and lack of human resources. To improve sanitation access through the SLBM program, it requires commitment among stakeholders, support local governments to equip CBOs with training, Improve Socialization, and invite communities in the SLBM program.
A Study of Mechanical Performance of Supplementary Cementitious Material using Hot Water Curing
Authors: Hamzah S , Aprianti E
Published: December 2019

This study aims to investigate mechanical properties of supplementary cementitious material (SCM) using different curing condition. The utilization of huge number of agricultural waste material due to amount type has been disposed-off and being hazardous to the environment. This problem lies into reuse and renew those wastes to be useful materials. The combination of industrial and agricultural waste materials were used up to 50% in order to replace the use of cement. The result showed that using different curing step could be an effective way to produce high mechanical performance of mortars using supplementary cementitious materials.
Environmental health risk analysis due to PM10 during 2015’s smoke haze pollution in Sawahlunto City
Authors: Goembira F , Amin M , Ihsan T , Djafri D
Published: December 2019

This research was aimed to analyzed metal concentrations in particulate matter 10 (PM10) sampled from ambient air in Sawahlunto City during the occurrence of smoke-haze pollution in 2015. The metal contents comprise of Al, Cr, Mn, Co, Ni, and Cd, which represented the potential for both non-carcinogenic and carcinogenic illnesses. The obtained metal concentrations were further used to estimate health risk on human by using environmental health risk assessment approach. PM10 samplings were done by using Minivol Air Sampler while the metal concentration analysis was conducted by atomic absorption spectrophotometer after PM10 filter destruction. It was found out that during the smoke-haze pollution the PM10 concentrations were above Indonesian air quality standard and considered at hazardous level in accordance to the Indonesian air quality index. The results of environmental health risk assessment for children and adults show the Hazard Quotient (HQ) value > 1 for non-carcinogenic metals (Al, Cr, Mn). As for the carcinogenic metals (Co, Ni, Cd), it was estimated that the Excess Lifetime Cancer Risk (ELCR) > 10-6 for both children and adults. It can be concluded that the occurrence of smoke-haze pollution in Sawahlunto City in 2015 increased the risk of cancer illnesses in both children and adults due to the high metal concentrations in PM10.
Resources-energy-development nexus and its implications for achieving the SDGs in Asia
Authors: McLellan B C , Watari T , Ogata S , Tezuka T
Published: December 2019

Growing modern economies are built on a variety of resources, and transitioning to the type of societies that are targeted by the Sustainable Development Goals (SDGs) will require a dramatic increase of clean energy (SDG 7) and resources consumption (SDG 12). At the same time, they must be provided within the limits of local environments, with a consideration of the balance of local and global impacts and benefits. Based on mineral production and reserves data for Asian countries, and the predicted requirements of minerals for clean energy technologies for their climate mitigation policy (SDG 13), supply-demand balances are calculated under a variety of scenarios. The potential for supply restrictions of identified “critical” minerals in each economy is demonstrated. Policy issues related to transboundary governance of energy and material flows and their economic and environmental costs and benefits (across the supply chain) to achieve equitable opportunities for all, including for emerging resources such as deep ocean mining (SDG 14) are then discussed on the basis of the “nexus”. This “nexus” of resources and energy offers a different perspective on the overall implications for development than either goal individually, and this is the first such study to target the Asian region holistically.
Chemical composition, fiber morphology, and kraft pulping of empty fruit bunch of dura variety (Elaies guineensis Jack)
Authors: Yahya R , Sariasih Y , Silsia D , Nuriyatin N , Desmantoro  , Mainaswati  , Elveri O
Published: December 2019

Fiber dimension, chemical component and pulp properties of biomaterial will directly affect the process, cost and quality of the paper produced, unfortunately until now it is very difficult to find information regarding these traits for Dura varieties. This study aims to examine the suitability of OPEFB of dura variety as paper raw materials based on those properties. Measurement of fiber dimension was carried out on maceration preparation made using Fraklin solution. Chemical components were determined by following the Tappi test method procedure. Pulp was made by the kraft method, then the properties were analyzed using Tappi test method and Scan. The results showed that this material had thin-walled fibers (2.79 ± 0.84um) with a medium length (1073.81 ± 373.63 um). This material contained extractive (7.19%) and holocellulose (67.69%) which were categorized high, and low in lignin (21.08%). The pulp produced yield (39.7%) and a high-categorized kappa number (23.3) and low alkali consumption (9.4%). Based on those values, OPEFB of dura variety was suitable as raw material for paper manufacture, although more efforts are still needed to increase the pulp yield value, due to the high value of “uncooked” pulp (32.43%).
Surveillance of ectoparasitic fungi Laboulbeniopsis termitarius thaxt and Antennopsis gallica buchli and heim on subterranean termite reticulitermes spp. in Japan
Authors: Guswenrivo I , Tarmadi D , Sato H , Fujimoto I , Yoshimura T
Published: December 2019

Ectoparasitic fungi grow on the body surface of termites, and they might effect on behavior, reproductive, and survival of host termites. There are two common species of ectoparasitic fungi found on termite:Laboulbeniopsis gallicaThaxt andAntennopsis gallicaBuchli and Heim. In this study, the distribution ofL. termitariusandA. gallicainReticulitermesspp. colonies in Japan was observed. Meanwhile, the infection rate and strength ofL. termitariusandA. gallicawere discussed with references to the effects of environmental factors at the collections sites. In a total of 63 colonies ofReticulitermesspp. were collected from seventeen locations (from Hokkaido Prefecture to Okinawa Prefecture) in Japan. Five hundred workers and twenty soldiers from each colony were examined individually to see the infection ofL.termitariusandA.gallica. The survey showed thatL.termitariusdistributed in whole Japan andA.gallicahad a little bit restricted distribution. The infection rate of workers ofReticulitermesspp. varied among all locations: 0.10 – 16.10% for L.termitariusand 0 – 66.40% for A.gallica.No infected soldiers were observed. The negative relationship between temperature and infection rate was speculated in both fungi. Rearing the colonies in the laboratory might result in the spreading of the fungi in the colonies. Both fungi grew on any body parts of the termites. The trials for isolation and cultivation ofLaboulbeniopsis termitariusand A.gallicawith eight media did not succeed under the laboratory conditions.
Groundwater level response of the primary forest, ex-peatland fire, and community mix plantation in the Kampar peninsula, Indonesia
Authors: Suryatmojo H , Imron M A , Gasa M S , Saputra D M , Maryani
Published: December 2019

Indonesia has voluntarily committed to mitigating climate change by reducing its greenhouse gas emissions by 26 percent by 2020 and 41 percent by 2050. More than half of this reduction was originated from the forestry/peatlands sector. Avoiding peat fires is therefore crucial for Indonesia to meet its targets. However, the efforts have been hampered by the fact that a large area of peatland has been burnt. The estimated extent of peatland and mangrove burnt was 2,124,000 Ha during the forest fire in Indonesia in 1997/1998. In 1997-1998, high carbon emissions made Indonesia as one of the largest global polluters. The peat fire occurrence in Indonesia has caused severe problems from environmental, economic, health also mortality. Indonesia has the largest peatland area in the region, which is 20.6 million ha or 10.8% of the land area. These lands are spread across various islands, 7.2 million ha (35%) in the Sumatera island, 6.6 million ha (32%) in Kalimantan island, 0.6 million ha (3%) in Sulawesi island and around 6.2 million ha (30%) in Papua island. Peatland in the Sumatera island has suffered severe damage due to land clearing and burning. The objective of this research is to determine the characteristics of peatland in various land conditions, namely primary forest, ex-peatland fire, and community mix plantation as well as to learn the dynamics of peat groundwater level in each study location. Rainfall and groundwater level sensors installed in the primary forest, ex-peatland fire, and community mix plantation. Rainfall-groundwater level analysis conducted to understand the hydrological response in various peatland characteristics. The results showed that in the ex-peatland fire and mix plantation have changed the peat soil characteristics with an increase of soil bulk density. This indicates decreasing the infiltration capacity, soil porosity and increase the surface water in the peatland area. Increasing the groundwater level response to rainfall is stable in the natural peatland forest. This indicates the function of forest cover as rainfall interception and reduces the volume and lag time of rainwater before reaching the forest floor. Community plantation with low canopy diversity has lower forest cover function than in the natural peatland forest. This will increase the volume of rainwater in the peat soil and increase the rainfall-groundwater level response much higher than in the natural forest. Maintain the diversity of canopy cover and reduce the open peatland by fire will control the hydrological response in groundwater level dynamics.
The role of agroforestry system for microarthropods biodiversity at upstream area of Merawu watershed, Banjarnegara District, Indonesia
Authors: Sokheang U , Ratha C , Suryatmojo H , Satriagasa M C , Dewi H N , Astuti H P , Retnoadji B
Published: December 2019

The role of agroforestry system is significant for the sustainability of land-use, soil, water, biodiversity, and environmental conservation. The soil microfauna and vegetation pattern are potential as ecosystem indicators to evaluate the quality of the environment. The research was conducted in the catchment area level, using 9 plots with difference stratification of up-stream, mid-stream, and downstream in the catchment. The nested quadrate divides into 6 layers of vegetation, and soil fauna sample is in the middle of the study plot. The soil microarthropods is observed by Berlese fauna method for 7 days and identify order by microscope and counting. The result indicates that the microarthropods in the agroforestry system shown in high abundance and biodiversity. Moreover, the vegetation pattern has a strong correlation with the microarthropods biodiversity. The research found that microarthropods biodiversity and vegetation pattern in the agroforestry system have a strong correlation and interaction. This relation will have a significant role to maintain the ecosystem balance on nutrient and water cycle in the catchment area. Farmers on agroforestry system provide both of environment and economics by following the natural role to support agroforestry system as an ecosystem service.
Experimental study on the effectiveness of finger joint with variations in wood species toward bending strength of glulam beams
Authors: Anshari B , Rofaida A , Mahmud F , Pathurahman  , Rahmalia R
Published: December 2019

Recently, the utilization of timber as building materials was very promising for now and future. As renewable resources they have high mechanical properties, lightweight, environmentally friendly and economic. One of the most durable engineered wood products is glued-laminated timber which commonly called Glulam. Glulam is a material made of several layers of wood glued together with waterproof adhesive at specific pressure and temperature. The benefit of Glulam is enable to produce the structural member with longer span compared with solid wood. In other to obtain the structural Glulam with longer span, it required the finger joint connection on lamina layer. This study aims at to find out the effectiveness finger joint with variation in wood species towards flexural properties of Glulam beam. Experimental study have been done by using local wood Sengon and Rajumas as laminae and Biomatex as adhesive, at 0.6 MPa of clamp pressure. The variation of finger joint slope was tested are 1:8; 1:12; and 1:16. The result show that the glulam Sengon and Rajumas beam with slope finger joint of 1 over 12 produce the highest average bending strength of 299 kg/cm2 and 318 kg/cm2 respectively. The flexural strength of glulam Rajumas was 20% higher compared with glulam Sengon.