scholarly journals Model of pneumohydraulic launch system

2020 ◽  
pp. 6-12
Author(s):  
М.В. Амброжевич ◽  
В.О. Середа
Keyword(s):  
Transport System ◽  
Spatial Model ◽  
Mathematical Apparatus ◽  
Integral Characteristics ◽  
Calculation Results ◽  
Physical Fields ◽  
Displacement System ◽  
Starting Characteristics

A reactive pneumohydraulic displacement system is proposed as an inclined launch system for an aircraft. The advantages of the proposed transport system in relation to the known analogs of comparable energy are stated. A complex non-stationary spatial model of the system is presented. The mathematical apparatus for constructing a model is considered. The calculation results are presented in the form of continual mappings of physical fields and integral characteristics of the launch system. The analysis of the starting characteristics for different proportions of equipment – the ratio of water and air. The conclusion is made about the effectiveness of the proposed launch system and the best equipment conditions.

scholarly journals Study on Micro Recoil Mechanism of the Weapon with a Nozzle and Two Chambers Separated by a Partition

2021 ◽  
Vol 2097 (1) ◽  
pp. 012009
Author(s):  
Longxu Ma ◽  
Ming Qiu ◽  
Jie Song ◽  
Peng Si ◽  
Zhenqiang Liao
Keyword(s):  
Two Phase Flow ◽  
Phase Flow ◽  
Ballistic Performance ◽  
Two Phase ◽  
Reduction Efficiency ◽  
Conventional Weapons ◽  
Calculation Results ◽  
Physical Fields ◽  
The One ◽  
Ballistic Model

Abstract In order to improve the recoil reduction ability of the weapon without reducing the projectile velocity, the weapon with a nozzle and two chambers separated by a partition is proposed. Taking the 35 mm caliber grenade launcher as the research object, the physical model of its launching process is proposed, and the one-dimensional two-phase flow interior ballistic model is established. MacCormack difference scheme is used to calculate the coupling of multiple physical fields formed by front and rear chambers and nozzles. Compared with the calculation results obtained by using the classical interior ballistic model, the correctness of the two-phase flow interior ballistic model is verified. The effects of the charge amount in the rear chamber and the size of the air guide hole in the barrel on the internal ballistic performance of the weapon with a nozzle and two chambers separated by a partition. The calculation results show that compared with conventional weapons, the recoil impulse can be reduced with maintaining muzzle velocity, and the recoil reduction efficiency can reach 72.27%, which is of great significance for improving weapon performance.

Simulation Analysis on Crowd Evacuation of the Subway Train Fire

2012 ◽  
Vol 424-425 ◽  
pp. 1215-1219 ◽  
Author(s):  
Xin Han ◽  
Jin Ning Ma ◽  
Bei Hua Cong
Keyword(s):  
Transport System ◽  
Fire Safety ◽  
Simulation Analysis ◽  
Urban Traffic ◽  
Safety Level ◽  
Software Simulation ◽  
Calculation Results ◽  
Subway System ◽  
Crowd Evacuation ◽  
Subway Train

Nowadays urban subway transport system has transformed its role from auxiliary facilities of urban traffic into a key component in people's lives. It is imperative to promote fire safety level of subway system. This paper simulates the crowd evacuation of the subway train fire. Four passenger densities within the train are set and the results of the software simulation with the calculation results based on specification are compared. It is relatively reliable to reflect the influence of the passenger density on the crowd evacuation, and some suggestions are also given out

scholarly journals Elastohydrodynamic Contact Model For Calculation Of Axial And Angular Stiffness In Thrust Bearing

2012 ◽  
Vol 59 (4) ◽  
pp. 453-467
Author(s):  
Mikhail Temis ◽  
Alexander Lazarev
Keyword(s):  
Fluid Flow ◽  
Thrust Bearing ◽  
Rotating Disk ◽  
Flow Calculation ◽  
Sliding Surfaces ◽  
Integral Characteristics ◽  
Calculation Results ◽  
Angular Displacements ◽  
Coupled Solution

Thrust bearing model is developed for fluid flow calculation and for determination of bearing integral characteristics in the presence of sliding surfaces closure and shaft angular displacements. The model is based on the coupled solution of the problem of incompressible fluid flow between the sliding surfaces and the problem of bearing and shaft elements deformation under the action of the fluid film pressure. Verification of the bearing model results is carried out by the comparison versus the fluid flow calculation results obtained by STAR-CD software and the experimental and theoretical results represented in the certain literature. Thrust bearing characteristics are determined versus sliding surfaces closure and rotating disk (runner) angular displacements. The contribution of the sliding surfaces deformations into bearing integral characteristics is estimated.

scholarly journals ANALISIS KINERJA PENGANGKUTAN SAMPAH PADA ZONA III KOTA BANDA ACEH (KECAMATAN LUENG BATA, KUTA RAJA DAN BAITURRAHMAN)

2019 ◽  
Vol 2 (4) ◽  
pp. 314-322
Author(s):  
Murnianti Murnianti ◽  
Syamsidik Syamsidik ◽  
Muhammad Zaki
Keyword(s):  
Transport System ◽  
Waste Disposal ◽  
Public Awareness ◽  
Primary Data ◽  
Waste Collection ◽  
Transportation Services ◽  
Transportation Time ◽  
Special Training ◽  
Calculation Results ◽  
Banda Aceh

The analysis of Waste Transportion Performance in Zone III of Banda Aceh managed to evaluate the waste transport system related to the pattern of waste collection and transportation, the frequency of transportation and the number of waste transport vehicles in zone III, so optimization can be done. Primary data is obtained by observing the process of transporting waste directly in the field and interviewing the parties that involved. Observations were made on each vehicle that carrying waste twice a day (morning and afternoon/night). The vehicles that will be observed consists of 11 dumptrucks, 1 compactor truck, 2 armrolltruck, so the number of observations is 14 days. The application of the pattern of waste collection with the door to door system in some zone III does not match the standards set. The amount of trip for dumptruck can be increased to 3 trips/day, 4 trip/day for compactors truck and 11 trips/day for armroll trucks. Better waste disposal can save dumptruck transportation time 2.18 hours/day or 27.26% and increase ritation to 3 trips/day. The addition of transport trips increases the potential amount of waste transportation up to 59.17% from 48.10 tons/day to 76.56 tons/day. The needs for waste transportation based on the calculation results can be optimized to 10 units, while currently used is 14 units. Inadequate of work equipment, there is no special training for workers and a lack of public awareness in properly disposing waste can be a barrier in waste transportation services.

scholarly journals The concept of "coincidental cargo transportation" as a mechanism to improve the efficiency of railway transport

2021 ◽  
Vol 7 (2) ◽  
pp. 130-141
Author(s):  
Viacheslav V. Yushchenko ◽  
Vladimir E. Khrapov
Keyword(s):  
Sustainable Development ◽  
Economic Evaluation ◽  
Transport System ◽  
Freight Transportation ◽  
Mathematical Apparatus ◽  
Railway Transport ◽  
Theoretical Methods ◽  
Cargo Transportation ◽  
Economic Foundations ◽  
Original Concept

Background: The formation of mechanisms for sustainable development of the transport system of Russia should be aimed at improving its competitiveness. Aim: Development of technical and economic foundations for improving the efficiency of the transport system of Russia, on the example of railway transport. Methods: Theoretical methods of scientific research were used to achieve the goal: analysis, synthesis and modeling. Results: The original concept of "Coincidental freight transportation" with the necessity of technical modernization of freight cars is offered. The concepts of a coincidental route and a coincidental wagon are analyzed, and application of the mathematical apparatus for economic evaluation of the results is recommended.

scholarly journals MODELING OF MARINE CONTAINER TRANSPORT SYSTEM ON THE BASIS OF THE MATHEMATICAL APPARATUS OF THE GRAVITY MODEL

2015 ◽  
Vol 7 (5) ◽  
pp. 26-33 ◽  
Author(s):  
Nikolaj Nikolaevich Majorov ◽  
◽  
Aleksandr Viktorovich Kirichenko ◽  
Vladimir Andreevich Fetisov ◽  
◽  
...  
Keyword(s):  
Gravity Model ◽  
Transport System ◽  
Mathematical Apparatus ◽  
Container Transport

On the structural organization of biological pumps and channels

1984 ◽  
Vol 42 ◽  
pp. 138-141
Author(s):  
G. Zampighi ◽  
M. Kreman
Keyword(s):  
Active Transport ◽  
Transport System ◽  
Plasma Membranes ◽  
Transport Proteins ◽  
Molecular Organization ◽  
Passive Transport ◽  
Concentration Gradients ◽  
Cell Functions ◽  
Natural Concentration ◽  
Active Transport System

The plasma membranes of most animal cells contain transport proteins which function to provide passageways for the transported species across essentially impermeable lipid bilayers. The channel is a passive transport system which allows the movement of ions and low molecular weight molecules along their concentration gradients. The pump is an active transport system and can translocate cations against their natural concentration gradients. The actions and interplay of these two kinds of transport proteins control crucial cell functions such as active transport, excitability and cell communication. In this paper, we will describe and compare several features of the molecular organization of pumps and channels. As an example of an active transport system, we will discuss the structure of the sodium and potassium ion-activated triphosphatase [(Na+ +K+)-ATPase] and as an example of a passive transport system, the communicating channel of gap junctions and lens junctions.

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