bluuebunny/crossref_metadata_2025_split huggingface dataset:
Preliminary Study on Properties of Oil Palm Shell Lightweight Concrete with Cockle Shell as Mixing Ingredient
Authors: Aris Shariza Mat , Carlos Philip Dick , Mohsin Sharifah Maszura Syed 
Published: September 2019

Abstract
Environmental pollution caused by the dumping of oil palm shell (OPS) from palm oil mill and cockle shell from cockle trade has initiated early exploration to discover the potential of these waste incorporated in concrete production. The present research investigates the effect of integrating crushed cockle shell as partial fine aggregate replacement on compressive strength and flexural strength of OPS lightweight aggregate concrete. A total of five mixes were prepared. OPS lightweight aggregate concrete containing 100% river sand was used as control specimen. Other mixes were produced by varying the percentage of crushed cockle shell by weight of sand. All specimens were water cured for 28 days before subjecting it to compressive strength and flexural strength. The finding shows the concrete exhibit strength increment when crushed cockle shell is added as partial fine aggregate replacement. Conclusively, crushed cockle shell has the potential to be used as mixing ingredient in OPS lightweight concrete production.
Utilization of Fly Ash in Construction
Authors: Ghazali Norhaiza , Muthusamy Khairunisa , Wan Ahmad Saffuan 
Published: September 2019

Abstract
In year 2016, Malaysia produce about 6.8 million tonnes of fly ash from six coal fired electric power station and this figure will increase due high demand of electric production. Fly ash is a waste product from the combustion of pulverized coal in electricity power plants and considered as a contributing factor for air, water and soil pollution that lead to human health problems and various geo-environmental issue. However, fly ash can be converted into valuable and useful product if properly utilized and many researches has been carried out in aim to increase the utilization of fly ash in various sectors especially in construction sector. In line with current economic conditions, all construction works required cost efficient with good quality of work. Therefore, fly ash is suitable to be used as an alternative raw material to enhance or replacing the existing construction material. In produce construction material many different industries and construction because it is oxide-rich material. The paper will be discussing the potential of managing waste of fly ash by utilizing it as construction materials.
Flexure Behaviour of Foamed Concrete Incorporating Banana Skin Powder and Palm Oil Fuel Ash Strengthened with Carbon Fibre Reinforced Plate
Authors: Mohamad Noridah , Afif Iman Muhammad , Aziz Abdul Samad Abdul , Othuman Mydin Md Azree , Jusoh Suriani , Sofia Anis , Aziz Khalidah , Lee Bryan 
Published: September 2019

Abstract
This paper investigated the chemical properties of banana skin powder (BSP) and palm oil fuel ash (POFA), and mechanical properties of lightweight foamed concrete (LFC) incorporating BSP and POFA strengthened with carbon fibre reinforce polymer (CFRP) plate. The BSP and POFA are added in the LFC mixture at various percentages as cement and sand replacement, respectively. LFC cubes incorporating BSP and POFA, LFC-BSP-POFA, were cast and tested under compression to determine its compressive strength. LFC-BSP-POFA prisms strengthened with 100 mm and 150 mm length of CFRP plates glued on its bottom mid-span surface were cast and tested under four point bending load to determine its flexure behaviour. From the chemical test, it was found that BSP and POFA each contain pozzolan materials, which are 55.98% and 51.83% silicon dioxide, and 2.71% and 2.32% aluminium oxide, respectively. From the mechanical property tests, compressive and flexural strength increased when percentage of BSP and POFA incorporated in the LFC increased. Meanwhile, CFRP plate managed to strengthen the LFC prism further where higher ultimate load recorded when longer CFRP plate was used.
Determining Changes in the Engagement of Screw Rotors Due to Transmission Error
Authors: Mustafin Timur , Yakupov Ruslan , Khamidullin Mansur , Alyaev Valery , Khisameev Ibragim 
Published: September 2019

Abstract
As a rule, the structural analysis of screw compressors during their design comes down to determining the geometric dimensions of the screws, the position of their window edges, as well as the gas forces acting on the compressor rotors. The latter determine the loads on the compressor bearings and affect vibration of the rotors and the compressor as a whole. Their effect plays the dominant role but not the only one. To create a mathematical model describing the vibration state of rotors, determining all additional forces acting on the compressor rotors that arise in the course of its operation under normal operating conditions is also required. These include the manufacturing inaccuracies causing skewing and bending of the rotor axles, as well as contact forces caused by the interaction of rotors due to their deviation from the nominal position. The latter are the least studied and, as a rule, are typical only for oil-flooded screw compressors with no rotor synchronisation mechanism. This article is devoted to the determination of rotor dynamics and the forces caused by rotor teeth engagement. In future, its results will serve as a basis for developing a rotor vibration state model. Meanwhile, the analysis of results obtained already at the current research stage allows to decrease their impact and effect.
CFD Modelling of Coupled Heat Transfer between Solid and Fluid in a Twin Screw Compressor
Authors: Ding Hui , Jiang Yu , Dhar Sujan 
Published: September 2019

Abstract
Temperature variation in a compressor is very critical for compression performance and efficiency. To accurately predict the thermal dynamic behaviour of a compressor, heat transfer between metal components and the working fluid needs to be properly evaluated in CFD simulation. Thermal expansion of solid components due to temperature increase may also cause excessive abrasion of metal parts and changing in leakage clearance. Solving conjugate heat transfer (CHT) of twin screw compressors not only needs to deal with complex moving rotor geometry, but also needs to consider huge difference of temperature propagation time scale inside different media. Typically, heat propagation is much slower in solid than in compressed gas. Therefore, it may take many compressor revolutions to reach a stable CHT solution if heat conduction inside solid and thermodynamic temperature change of compressed gas are directly coupled in a CFD simulation. The run time of simulation may become impractical.
In this paper, an innovative approach solving conjugate heat transfer using the Mixed Timescale Coupling method between different media will be described in detail. This approach can address time scale difference in heat propagation. The proposed approach will be applied to a twin screw compressor. Simulation results will be compared with available test data. Effects of conjugate heat transfer will be evaluated by comparing the simulation results for the cases with and without considering conjugate heat transfer. Thermal expansion of the solid rotor will also be evaluated using predicted temperature distribution. Simulation will also demonstrate that the approaches used in the paper are robust, fast, and user friendly, and can be readily applied to industrial compressor systems.
Use of CFD to Investigate Flow Characteristics and Oil Distribution Inside an Oil-injected Screw Compressor
Authors: Zhang J W , Wu Y R , Hsieh S H , Huang C S 
Published: September 2019

Abstract
The well-developed CAE tools are used to investigate flow characteristics and oil distribution inside an oil-injected screw compressor. The flow field of gas mixed with oil is calculated by ANSYS CFX. TwinMesh generates high quality hexahedral grids for the compression chambers. There are two cases studied in this study. In the first case, the compressor models under four loading conditions are analyzed. The pressure curve is used to see if the designed built-in volume index is appropriate. In the second case, the compressor models under oil-free and oil-injected conditions are analyzed. The pressure gradients on rotor surfaces and velocity vector fields are used to describe the effects of lubrication and sealing in the sealing line gap, the tip gap, and the outlet end gap of rotors. The designer could optimize the slider and know if the oil is properly distributed in each gap.
An experimental investigation on pulsation & noise reduction by shunt pulsation trap with a nozzle for compressors operating in under-compression
Authors: Huang P X , Yonkers S 
Published: September 2019

Abstract
This paper is a continuing work from the same authors on the same topic on gas pulsation and noise control using a shunt pulsation trap (SPT) method by Huang [1, 2, 3]. Traditionally, a serial pulsation dampener/muffler, often a reactive type, is connected AFTER the discharge of a positive displacement compressor. It has been demonstrated in the previous experimental investigations that gas pulsations from under-compression (UC) can be as effectively controlled by an alternative scheme - shunt pulsation trap (SPT), which is more compact and tackles the gas pulsations BEFORE the compressor discharge. Two dampening SPT schemes were investigated and compared: using a perforated plate (p-plate) vs. a perforated tube (p-tube). However, the pulsation induced noise is still a challenge with SPT employment alone. The focus of the present paper investigates experimentally the effect of a new dampening scheme - combining a SPT with a nozzle and an integrated absorptive silencer (IAS) to undertake both pulsation and noise problems at source. It is found that an ASME nozzle SPT with IAS scheme has superior noise reduction capability than both the p-tube + IAS scheme and the traditional scheme using premium silencers. Furthermore, the addition of an integrated absorption silencer (IAS) is not suffering as much back pressure drop associated with traditional reaction type silencers and therefore will not affect system efficiency. The integration of absorptive silencer into a nozzle or p-tube based SPT would provide an optimal design choice for size/weight and pulsation/noise reduction and potentials for energy saving for PD compressors operating in UC mode.
Vapor Compression Cycles for High Component Heat Loads on Next-Generation Small Satellites
Authors: Brendel Leon P M , Hengeveld Derek , Braun James E , Groll Eckhard A 
Published: September 2019

Abstract
High-power small satellites (SmallSats) have the potential to provide new and advanced capabilities; however, significant challenges prevent wide-spread use. Of these challenges, thermal management of high heat loads is most significant. This paper evaluates vapor compression cycles (VCCs) as a thermal management solution to increase the maximum component heat load at a fixed radiator area. The VCC with radiative heat transfer as a heat sink is described with analytical equations that couple the required compressor work input for a desired additional component heat load for a given second law efficiency. A figure of merit is defined. In a case study, the results of the equations are compared to a numerically modelled vapor compression cycle. Challenges for a realization of vapor compression cooling on-board SmallSats are pointed out.
Developing teamwork skills for students trained in compressors and refrigeration programs
Authors: Fedorova M A , Prokudina N A , Fedoseeva N Yu , Evdokimov  , Kapelukhovskaya A A , Yusha V L 
Published: September 2019

Abstract
While implementing the bachelor’s program in the fields of compressors and refrigeration, modern educational standards provide for the teamwork competence developing. The purpose of this study is to propose a system of developing this competence for students of the Petrochemical Institute, Omsk State Technical University. The main idea of the research is the application of an integrated interdisciplinary approach to all the competences of the graduate, involving various forms and methods of implementing the system of training highly skilled engineers. The team-building competence is formed both during instruction time and extracurricular time: in research, internships, sport and other activities. In addition, the work experimentally revealed that the competence under consideration is consistent with both the requirements of employers and the need for students self-realization while studying at a university. The article presents particular examples of this competence development in the course of basic professional subjects, as well as of Foreign language and Physical education. In particular, the Foreign language course was extended for the students of the mentioned training programs in comparison with other students. As for physical education, team skills are formed in the classroom and through the students participation in various sport competitions. Besides, the article describes the results of students participation in the program “Young professionals of Russia”, WSR. In addition, the interdisciplinary Petrochemical Institute project of the summer school for the first-year undergraduates, fully implementing the principles of complexity and consistency, is presented in the paper.
Vaneless diffusers characteristics simulating by means of neural networks
Authors: Nikiforov A , Avramenko D , Kuchumov A , Terentev S , Galerkin Yu , Solovyeva O 
Published: September 2019

Abstract
The paper presents the results of simulation of loss coefficient and the angle of flow at the outlet of diffuser in centrifugal compressor vaneless diffusers. The calculation was performed in a wide range of design and gas-dynamic parameters by means of neural networks. Also, an analysis performed by CFD (Computational Fluid Dynamics) methods is presented. In order to obtain mathematical models, a data sampling was used for vaneless diffusers with the following characteristics: relative width is b
2 / D
2 = 0.014 – 0.1, outlet relative diameter is D4 / D2 = 1.4 – 2.0, inlet flow angle is 2 α2 = 10 – 90 º, velocity coefficient is λ
c2 = 0.39 – 0.82, Reynolds numbers corresponding to them are Re
b2
= 87 500 - 1 030 000.
In order to improve the accuracy of simulating using neural networks, various recommendations on the preparation and processing of initial data were collected and tested: identification of conflict samples and outliers, data normalization, improving the quality of the neural networks training under the insufficient amount of sampling, etc. Application of the listed recommendations and an essential expansion of mathematical models definition significantly improved the accuracy of simulating.
A simulation experiment based on neural models for studying the influence of dimensions, diffuser shape, and similarity criteria made it possible to check the physical adequacy of mathematical models, to obtain new data on energy conversion processes and to establish a number of recommendations on the optimal design of vaneless diffusers.
Optimization of geometry blade for modern high pressure compressor
Authors: Marchukov E , Egorov I , Kretinin G , Karonic B , Fedechkin K. 
Published: September 2019

Abstract
An integration of CFD-3D codes and modern efficient methods of optimization is essential for the contemporary compressors improvement. In order to solve optimization tasks the insular information exchange circle was created. The data circulates between the mathematical model of the stream in a compressor, the algorithm of compressor’s geometry construction based on parameterization and algorithm of optimization itself. The mathematical model of the compressor covers procedures of mesh generation and calculations using CFD code. This model has been verified by experimental data.
A high-pressure compressor of multi regime gas turbine engine for supersonic civil aircraft has been considered as the object of our study. The goal of the research was to increase the efficiency in the design point with the ensured preset gas dynamic parameters under other modes. The variables for optimization task were installation angles and the shape of the middle line of the profile in three sections along the height of the compressor rotor and stator blades. The total amount of independent variables was 72. As a result of the study the optimal geometry for the stator and rotor blades in supersonic aircraft engine has been obtained. The initial project efficiency had been improved by 1-2%, while stability margin remained constant.
Detailed prediction of fluid-solid coupled phenomena of turbulent flow through reed valves
Authors: González I , Naseri A , Rigola J , Pérez-Segarra C D , Oliva A 
Published: September 2019

Abstract
The operation of self-actuated valves in suction and discharge processes plays a crucial role in the thermal efficiency and structural reliability of hermetic reciprocating compressors. The present work provides a thorough description of an in-house numerical method based on a partitioned fluid-structure interaction algorithm intended to obtain high-fidelity numerical predictions and optimise valve system design. A large eddy simulation model is used for the turbulent flow, whereas a normal mode superposition assumption along with an impact penalty method is used for the reed. Under this framework, a detailed analysis of the coupled problem with a straight and tapered exit ports is carried out. Differences in effective flow area and pressure drop are found as a result of the port geometry, but also of the valve velocity.
Development of Augmented Reality Applications for the Entire Spectrum of Screw Compressor Manufacturing Process
Authors: Milligan W J , Gillan S M , Harrison D K 
Published: September 2019

Abstract
Augmented Reality (AR) in industrial applications connects users across digital and physical worlds and coupled with rapid return of investment, easy adoption, and as a meaningful way to stand out from the competition, AR is quickly becoming increasingly common in the industrial world. This paper first provides the reader with a description on what exactly is augmented reality and the difference between augmented reality and virtual reality, before moving onto describing the scope of this new application for an organisation like Howden. A brief analysis of how augmented reality is quickly finding a footing within this sphere is offered alongside an overview of the main players and actors. The paper then focuses on how the 3D CAD modelling already completed by the research and development, bare-shaft engineering and package engineering teams can be utilised in the rapid development of augmented reality applications. Examples of how Howden are developing and using these AR applications are then given with specific reference to the Screw sales teams using them to show prospective clients the model of their package / machine; the Screw package build teams sharing knowledge using AR during package fit-out and hazard and operability studies; the bare-shaft test team using AR within their acoustic enclosure and finally the impact of AR in the service teams. The paper concludes with how, as this technology becomes more mainstream, manufacturers adopting AR can significantly add value to their customers experience both in terms of service and satisfaction but also differentiate themselves from their competitors.
Dietary supplementation with garcinol during late gestation and lactation facilitates acid–base balance and improves the performance of sows and newborn piglets1
Authors: Wang Tongxin , Yao Weilei , Xia Jun , Li Juan , Shao Yafei , Huang Feiruo 
Published: September 2019

AbstractThe present study was conducted to evaluate the effects of dietary garcinol supplementation during late gestation (from the 90th day of pregnancy; day 90) and lactation on the acid–base balance of the umbilical cord blood and performance of sows and piglets. Sixty sows (Duroc × Yorkshire × Landrace; second- or third-parity; n = 20) were randomly divided into 3 gestation (day 90 of pregnancy) or lactation treatments, control diet (CON; basal diet), basal diet with 200 mg garcinol, and basal diet with 600 mg garcinol per kg of feed. The body weight (BW); backfat thickness and litter size of the sows; and birth weight, weaning weight, and mortality of piglets were recorded. Sows’ blood and piglets’ umbilical cord blood were collected for the measurements of hematological parameters and antioxidative and immune indexes, and acid–base balance parameters, respectively. The colostrum and milk and fecal samples of the sows were also collected for analysis of milk composition and apparent total tract nutrient digestibility. Garcinol had no effect on the BW and backfat thickness of the sows but significantly increased the birth weight and weaning weight of piglets (P < 0.05) and decreased the mortality (P < 0.05). Moreover, the white blood cell counts and neutrophil count, mean cell hemoglobin, superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and catalase (CAT) activity in the plasma of the sows were increased more significantly (P < 0.05) in the garcinol groups than that in the CON group, whereas the malondialdehyde (MDA) content was decreased (P < 0.05). The garcinol treatment significantly increased the pH, HCO3− and base excess values (P < 0.05), whereas it decreased the pCO2 and lactate content (P < 0.05) in the umbilical blood. Dry matter (DM), ash, and ether extract in the colostrum were similar between groups (P > 0.05), whereas the garcinol significantly increased the crude protein (CP) in the milk. In addition, the content of immunoglobulin A (IgA) and immunoglobulin G (IgG) in the plasma of piglets and in colostrum and milk of sows were increased more significantly (P < 0.05) in the garcinol groups than that in the CON group. The apparent total tract nutrient digestibility was similar between treatments. Collectively, this study indicates that sows fed with garcinol in late gestation and lactation showed improved maternal health and antioxidative status, milk protein content, acid–base balance in the umbilical cord blood, and growth performance in piglets, showing promise in natural plant extract nutrition for sows.