Analysis of Hybrid Bus Powertrain With Different Transmissions

2011 ◽  
Author(s):  
Mohamed E. M. El-Sayed ◽  
Jeffrey Barber
Keyword(s):  
Hybrid System ◽  
Duty Cycle ◽  
System Integration ◽  
System Development ◽  
Low Cost ◽  
Power Train ◽  
Duty Cycles ◽  
Hybrid Bus ◽  
Train System ◽  
Two Alternatives

The main goals for developing hybrid power train system are reducing emissions and providing commercially viable low cost transportation solutions. To achieve these goals, a well defined set of targets and specifications are necessary for the hybrid system development. These targets and specifications are needed for design, analysis, and validation of the power train subsystems, components, and successful system integration. During hybrid system design and development, there are many alternatives and design configurations to choose from. To select the most efficient systems duty cycle data and profiles are needed to assist in defining the design targets and specifications. For buses, due to their well defined routes the duty cycles can be achieved through data acquisitions or by using the American Public Transit Association (APTA) standard duty cycle. In this paper, the APTA duty cycle profiles are used to evaluate two alternatives power train configurations for a bus series hybrid system. The first configuration consists of two electric motors and one speed transmission while the second configuration consists of one electric motor with two speed transmission. The simulation and analysis results of both configurations are presented.

The Simulation on the Power Train System of the Hybrid Horizontal Directional Driller

2011 ◽  
Vol 127 ◽  
pp. 233-236
Author(s):  
Tao He ◽  
Li Xin Meng ◽  
Zhi Qiang Liu
Keyword(s):  
Hybrid System ◽  
Developed Countries ◽  
Power Train ◽  
Working Cycle ◽  
Rapid Construction ◽  
Control Goal ◽  
Parallel Hybrid ◽  
The Developed Countries ◽  
Train System ◽  
Engine Power

As technology and equipment improves, the horizontal directional driller was gradually accepted in the developed countries in the 1980s. With the rapid construction of urbanization, non-excavating technology is widely used in China. In this paper, a new kind of hybrid technology in the horizontal directional driller is presented. Taking HL518B as a prototype, a parallel hybrid system is designed .The control strategy of the hybrid horizontal directional driller is analyzed on the basis of the several operations in the working cycle. The control goal of whole system is to realize the torque demand of loading. Research is made on how to transform the single engine power into the hybrid power train, At same time the model of hybrid system is established and simulated. The simulation results show the hybrid system can effectively improve the horizontal directional driller fuel economy.

Acoustic-Reflex Dynamics for Pulsed Signals

1978 ◽  
Vol 21 (2) ◽  
pp. 295-308
Author(s):  
Terry L. Wiley ◽  
Raymond S. Karlovich
Keyword(s):  
Duty Cycle ◽  
Acoustic Impedance ◽  
Normal Hearing ◽  
Broadband Noise ◽  
Threshold Shift ◽  
Temporary Threshold Shift ◽  
Acoustic Reflex ◽  
Stapedius Muscle ◽  
Duty Cycles

Contralateral acoustic-reflex measurements were taken for 10 normal-hearing subjects using a pulsed broadband noise as the reflex-activating signal. Acoustic impedance was measured at selected times during the on (response maximum) and off (response minimum) portions of the pulsed activator over a 2-min interval as a function of activator period and duty cycle. Major findings were that response maxima increased as a function of time for longer duty cycles and that response minima increased as a function of time for all duty cycles. It is hypothesized that these findings are attributable to the recovery characteristics of the stapedius muscle. An explanation of portions of the results from previous temporary threshold shift experiments on the basis of acoustic-reflex dynamics is proposed.

scholarly journals Sensor Networks for Structures Health Monitoring: Placement, Implementations, and Challenges—A Review

Vibration ◽  
2021 ◽  
Vol 4 (3) ◽  
pp. 551-584
Author(s):  
Samir Mustapha ◽  
Ye Lu ◽  
Ching-Tai Ng ◽  
Pawel Malinowski
Keyword(s):  
Sensor Networks ◽  
Health Monitoring ◽  
Data Transmission ◽  
System Integration ◽  
Structural Integrity ◽  
Low Cost ◽  
Data Communication ◽  
Total Cost ◽  
Design And Optimization ◽  
Successful Case

The development of structural health monitoring (SHM) systems and their integration in actual structures has become a necessity as it can provide a robust and low-cost solution for monitoring the structural integrity of and the ability to predict the remaining life of structures. In this review, we aim at focusing on one of the important issues of SHM, the design, and implementation of sensor networks. Location and number of sensors, in any SHM system, are of high importance as they impact the system integration, system performance, and accuracy of assessment, as well as the total cost. Hence we are interested in shedding the light on the sensor networks as an essential component of SHM systems. The review discusses several important parameters including design and optimization of sensor networks, development of academic and commercial solutions, powering of sensors, data communication, data transmission, and analytics. Finally, we presented some successful case studies including the challenges and limitations associated with the sensor networks.

Computational Fluid Dynamic Applications for Jet Propulsion System Integration

1991 ◽  
Vol 113 (1) ◽  
pp. 40-50 ◽  
Author(s):  
R. H. Tindell
Keyword(s):  
System Integration ◽  
Fluid Dynamic ◽  
Low Cost ◽  
Separated Flow ◽  
Propulsion System ◽  
Navier Stokes ◽  
Aerospace Vehicles ◽  
Design Engineers ◽  
Flow Phenomena ◽  
The Impact

The impact of computational fluid dynamics (CFD) methods on the development of advanced aerospace vehicles is growing stronger year by year. Design engineers are now becoming familiar with CFD tools and are developing productive methods and techniques for their applications. This paper presents and discusses applications of CFD methods used at Grumman to design and predict the performance of propulsion system elements such as inlets and nozzles. The paper demonstrates techniques for applying various CFD codes and shows several interesting and unique results. A novel application of a supersonic Euler analysis of an inlet approach flow field, to clarify a wind tunnel-to-flight data conflict, is presented. In another example, calculations and measurements of low-speed inlet performance at angle of attack are compared. This is highlighted by employing a simplistic and low-cost computational model. More complex inlet flow phenomena at high angles of attack, calculated using an approach that combines a panel method with a Navier-Stokes (N-S) code, is also reviewed. The inlet fluid mechanics picture is rounded out by describing an N-S calculation and a comparison with test data of an offset diffuser having massively separated flow on one wall. Finally, the propulsion integration picture is completed by a discussion of the results of nozzle-afterbody calculations, using both a complete aircraft simulation in a N-S code, and a more economical calculation using an equivalent body of revolution technique.

scholarly journals Characteristics of Low Frequency Non-Synchronous Vibrations Induced by an Epicyclic Gearbox in Gas Turbogenerator Applications

1998 ◽  
Author(s):  
A. K. Rakhit ◽  
G. A. Cornejo ◽  
G. J. Lack
Keyword(s):  
Low Frequency ◽  
Output Shaft ◽  
Power Train ◽  
Backward Whirl ◽  
Considerable Length ◽  
Potential Damage ◽  
Generator Sets ◽  
Star Configuration ◽  
Train System ◽  
Total Elimination

Epicyclic gearboxes of star configuration running at partial loads were found to induce non-synchronous (not related to speed) low-frequency vibrations, besides low level sub-synchronous (speed related) which were transmitted to other parts of a turbogenerator power train. At certain loads, the amplitudes of the non-synchronous vibrations were high enough to cause potential damage to sleeve bearings used in the power train system if a generator set would run for any considerable length of time at these loads. It was also observed that a very small increase in load above a certain limit (about 18% of full load) resulted in almost total elimination of these vibrations. Analysis of test data showed the non-synchronous vibrations were due to ‘backward whirl’ motion of gearbox output shaft in its sleeve bearings. Higher damping in the bearings was considered to be one of the most effective methods to suppress backward whirl of a shaft and hence, the non-synchronous vibrations. Accordingly, a new set of gearbox output shaft sleeve bearings was designed for higher damping that would allow these types of generator sets to run at partial and full loads without any detrimental vibration.

Sign in / Sign up

Export Citation Format

Share Document