Feasibility studies on utilization of low-pressure in hydro-pneumatic driveline

The aim of this paper is to present a feasibility study on the use of low pressure in  vehicle’s small applications. Hydro-pneumatic driveline is one of the hybrid sub-systems for  hydraulic hybrid vehicle. Usually, the energy supplied by hydro-pneumatic accumulator/storage operates through maximum energy level to a minimum. This often reaches  to the point where the limit of minimal operations is higher than the pre-charge limit. The remaining power is claimed as not effective to move a vehicle, but the pressure still contains energy. Therefore, it is a waste of energy.  The pressure energy can be used to power vehicle’s small applications such as fan, starting motor, compressor,  hybrid electric battery charger, and others. Hence, a laboratory-scale experiment was extended away to see the hydro-pneumatic drive system behavior to operate at low-pressure level. Through the experiment, it was found that the system can work at low-pressure level. However, the power generated was 740 watt, 16.2 Nm theoretical torque and operated at 52 % efficiency at a pressure of 50 bar. This value is too small if compared to the force needed to move the vehicle. Still, it was dependable enough to power the small application in the vehicle sub-system. Through this research, it is hoped that the ineffective pressure of the hydraulic hybrid vehicle can be utilized so it can contribute to the increase of efficiency

Determination of Optimal Electrospinning Distance and Applied Voltage for Polyacrylonitrile Electrospun Fibre Production

Electrospinning process is highly dictated by electric field strength. Thus, two key parameters i.e., electrospinning distance and applied voltage, determine the quality of electrospun fibres. Incorrect selection of these parameters will result in poor fibre qualities. There ought to be an optimal combination of electrospinning distance and applied voltage to produce best quality fibres from a given material. In this study, the optimal combination of electrospinning distance and applied voltage was assessed based on consistency of electrospinning process, amount of fibre, fibre morphology, and average fibre diameter. Polyacrylonitrile (PAN) electrospun fibre samples were prepared at different combinations of electrospinning distance and applied voltage. Scanning electron microscopy and image analysis were conducted to assess the quality and average diameter of the fibres. The results indicate that for electrospinning of PAN, the distance should be between 10 and 20 cm with a 15 to 20 kV of applied voltages. Findings from this study is crucial for producing optimal fibre quality in PAN electrospun nanofibre synthesis

Simulation of Storage Performance on Hydro-Pneumatic Driveline

The charging process is one of the critical processes in the hydro-pneumatic driveline storage system. It converts the kinetic energy of the vehicle braking and coasting to the compression energy. This energy is stored in the storage device called the accumulator. The system is planned to be used on the dual hydro-pneumatic hybrid driveline and applied to a hydraulic hybrid passenger car. The aim of this paper is to find the effect of charging parameters on the storage performance through simulation. Through the storage behavior, the desirable and optimal sizing of the accumulator can be selected. The paper emphasized on the effect of pressure elevation, pre-charge pressure, effective volume, thermal reaction and required time of the accumulator's charging process. The circuit of charging process has been designed and simulated by using the hydraulic tool in the Automation Studio software. The simulation results were corroborated through the component specification for data rationality. Through the simulation, it was found that pre-charge pressure had a significant effect on the charging process. It determined the efficiency of the effective volume. The higher the pressure elevation, the higher the effective volume. Nevertheless, the more energy required to compress the nitrogen gas in the bladder. Besides, in term of volume displacement, higher volume displacement reduced charging time and lower the fluid temperature. The simulation had been positively highlighted the critical point in charging process which later on, benefited the sizing process in the component selection specification

Feasibility Studies on Utilization of Low-Pressure in Hydro-pneumatic Driveline

The aim of this paper is to present a feasibility study on the use of low pressure in vehicle’s small applications. Hydro-pneumatic driveline is one of the hybrid sub-systems for hydraulic hybrid vehicle. Usually, the energy supplied by hydro-pneumatic accumulator/storage operates through maximum energy level to a minimum. This often reaches to the point where the limit of minimal operations is higher than the pre-charge limit. The remaining power is claimed as not effective to move a vehicle, but the pressure still contains energy. Therefore, it is a waste of energy. The pressure energy can be used to power vehicle’s small applications such as fan, starting motor, compressor, hybrid electric battery charger, and others. Hence, a laboratory-scale experiment was extended away to see the hydro-pneumatic drive system behavior to operate at low-pressure level. Through the experiment, it was found that the system can work at low-pressure level. However, the power generated was 740 watt, 16.2 Nm theoretical torque and operated at 52 % efficiency at a pressure of 50 bar. This value is too small if compared to the force needed to move the vehicle. Still, it was dependable enough to power the small application in the vehicle sub-system. Through this research, it is hoped that the ineffective pressure of the hydraulic hybrid vehicle can be utilized so it can contribute to the increase of efficiency

Simulation of Storage Performance on Hydropneumatic Driveline in Dual Hybrid Hydraulic Passenger Car

The charging process is one of the critical processes in the hydro-pneumatic driveline storage system. It converts the kinetic energy of the vehicle braking and coasting to the compression energy. This energy is stored in the storage device called the accumulator. The system is planned to be used on the dual hydro-pneumatic hybrid driveline and applied to a hydraulic hybrid passenger car. The aim of this paper is to find the effect of charging parameters on the storage performance through simulation. Through the storage behaviour, the desirable and optimal sizing of the accumulator can be selected. The paper emphasized on the effect of pressure elevation, pre-charge pressure, effective volume, thermal reaction and required time of the accumulator’s charging process. The circuit of charging process has been designed and simulated by using the hydraulic tool in the Automation Studio software. The simulation results were corroborated through the component specification for data rationality. Through the simulation, it was found that pre-charge pressure had a significant effect on the charging process. It determined the efficiency of the effective volume. The higher the pressure elevation, the higher the effective volume. Nevertheless, the more energy required to compress the nitrogen gas in the bladder. Besides, in term of volume displacement, higher volume displacement reduced charging time and lower the fluid temperature. The simulation had been positively highlighted the critical point in charging process which later on, benefited the sizing process in the component selection specification

The effects of multiple storages on performance of hydro-pneumatic hybrid driveline

The study emphasis on the effect of multiple storages on the performance of hydro-pneumatic hybrid driveline. Passenger’s car space is very limited. Therefore, the initial solution suggested to use smaller storage, but more in numbers. Its small size allows it to be placed several locations in the car while the number increases the storage capacity. An experiment was carried out to see the system behaviour. It was found that the multiple storages produced better power. However, the torque and efficiency had an adverse effect because of the increase of motor speed, pressure drop, and flow limitation

A Review of Compressed-air Hybrid Technology in Vehicle System

The aim of this paper is to present a comprehensive review of the compressed-air hybrid technology in a passenger and commercial vehicle since the beginning of its discovery to date. Hybrid technology has become popular in the automotive industry since the technology proven to improve the vehicle efficiency, saving in fuel use and green environmental. The well-known hybrid technology is hybrid electric. Nevertheless, the price of the hybrid electric automobile is high, the arrangement is complex, and it is not completely green. These disadvantages have triggered innovation in a hybrid technology called compressed-air hybrid technology. The compressed-air hybrid technology uses a combination of ICE and fluid power components as a propulsion unit and compressed-air energy as a power source. The energy stored in the tank/accumulator. Once the energy in the storage is low, the system utilizes energy losses in braking and recovers into useful energy. This article concentrates on the hybrid compressed-air design, components, latest finding, technology breakthrough, benefit and drawback of the system. The review also encompasses the most recent prototype that has been tested. Based on the study, the literature has shown that the compressed-air hybrid system is proven to work. Nevertheless, further research needs to extend out to resolve a few topics such as amending the energy capability and lightweight system design. The two-subsystem are promising, but nevertheless far from the point of commercialization. However, the three-subsystem has been proven in saving energy and fuel consumption. Although it still needs to be further refined, it has a huge potential to get into the market. The compressed-air hybrid technology in a passenger car is still new. There is a huge room to explore. If the hybrid compressed-air technology is successful, clearly it will benefit the future in the aspect of energy efficiency, cost saving, and reduce the pollution

Comparison of hydro-pneumatic accumulator's charging performance under different thermal process for dual hybrid driveline

The hydro-pneumatic accumulator is broadly used in heavy industry as leaking compensator. Lately, much interest has been developed to study the component as energy storage. The important element in the selection of accumulator is performance. Hence, research was conducted to examine the use of thermal process condition and its impingement on the accumulator as an energy store. For charging process, the performance is influenced by the thermal process because it involves temperature change and heat transfer. Both processes are producing a different performance. The storage system is planned to be adapted in the dual hybrid driveline. A simulation study has been conducted by using Automation Studio software which focusses on two different processes called isothermal and adiabatic. The process has involved a schematic design, functional testing, parameter setting, and pretense. The result has shown that the thermal process affected the fluid power parameters such as power, effective storage capacity, and temperature differentials. The isothermal process produced higher effective volume compared to adiabatic process, stored higher power and had lower temperature differentials. Regarding charging speed, the adiabatic was faster. However, it was a lack of storage capacity

Determination of optimal electrospinning distance and applied voltage for polyacrylonitrile electrospun fibre production

Electrospinning process is highly dictated by electric field strength. Thus, two key parameters i.e., electrospinning distance and applied voltage, determine the quality of electrospun fibres. Incorrect selection of these parameters will result in poor fibre qualities. There ought to be an optimal combination of electrospinning distance and applied voltage to produce best quality fibres from a given material. In this study, the optimal combination of electrospinning distance and applied voltage was assessed based on consistency of electrospinning process, amount of fibre, fibre morphology, and average fibre diameter. Polyacrylonitrile (PAN) electrospun fibre samples were prepared at different combinations of electrospinning distance and applied voltage. Scanning electron microscopy and image analysis were conducted to assess the quality and average diameter of the fibres. The results indicate that for electrospinning of PAN, the distance should be between 10 and 20 cm with a 15 to 20 kV of applied voltages. Findings from this study is crucial for producing optimal fibre quality in PAN electrospun nanofibre synthesis