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This paper presents simulation study on the effects of the cross-sectional area at the merging region and high pressure compressed airflow rate on the flow energy merger, and their optimum adjustments for the change in the compressed air pressure ( P air ) in the hybrid pneumatic power system (HPPS). The simulation of energy mixing and merging processes was performed for an innovative energy merger pipe in which the open angle ( A ) of the air storage tank’s throttle valve and the contraction of the cross-sectional area (CSA) at the merging region of the energy merger pipe can be adjusted for changes in P air . The simulations were carried out using computational fluid dynamics (CFD). The results showed that the exhaust-gas recycling efficiency and the merger flow energy are significantly dependent on the optimal adjustments of A and CSA for the change in P air . The optimal conditions for higher exhaust-gas recycling efficiency and the best energy merging process can be achieved at A of around 25–100% and a CSA of around 5–40% for a full range of P air . Under these conditions, the exhaust-gas recycling efficiency reached approximately 80–88%. Therefore, a vehicle equipped with an HPPS can achieve a level of efficiency that is approximately 40% higher than that of conventional vehicles.

If vehicles can be more comfortable, safe, energy efficient and humanized, it will be very beneficial. This study introduces an “Airflow Management” technique to control the airflow in the vehicle cabin for the purpose of achieving a regional steady-state temperature. With this new concept, each passenger in a different area of the compartment can be satisfied with respect to his/her unique temperature demands. The airflow is controlled by air inlets and outlets, with fans for the modulation of airflow directions and rates. The temperature in each zone can be controlled by the modulation of the airflow. The concepts in this study are relevant to all kinds of regional air-conditioning in any enclosed space.

The hybrid pneumatic power system (HPPS) proposed in this research replaces the battery’s electric-chemical energy with flow work and optimizes the management and utilization of the energy. This power system is able to keep the internal-combustion engine working at its optimal condition and turn its waste energy into effective mechanical energy and so enhance the thermal efficiency of the whole system. Using computer simulation software ITI-SIM, this study simulates the overall dynamic characteristics of the system in accordance with the regulated running-vehicle test-mode ECE47, and, with experimental verification and analysis, proves that this system can meet the requirements of the standard running-car mode. As for recycling the waste energy, the experimental results show that this design could offset the shortcomings of the low-density of pneumatic power and so effectively enhance the efficiency of the whole system.

The power system enables the internal-combustion engine to function at its optimal operating point without a complicated controller. The waste heat from the internal-combustion engine can be recycled and stored, then converted into mechanical energy, thereby raising the overall thermal efficiency of this system. A computer-aided simulation program is used to simulate the overall dynamic features of this hybrid pneumatic-power system, so as to demonstrate its desirable features.The overall efficiency of this system is expected to increase by about 20%.

This research has designed a new hybrid-electric system, which is characterized by two mechanisms: internal-combustion engine energy-distribution mechanism and dual energy-integration mechanism. The internal-combustion engine energy-distribution mechanism comprises a first pulley-set and a second pulley-set, whereby it is possible to adjust its radius ratio and change the output load according to the road-surface, output speed and corresponding load to maintain an optimal operating state of engine for a given generator rotational-speed. In this way, the engine can function in its optimal state. For a dual energy-integration mechanism, any power source can be individually actuated by the electric motor and the power transmitted from the internal-combustion engine energy-distribution mechanism. Moreover, a one-way clutch can prevent the actuated power source from reversion, so any output power source will not be affected by any inactive power. Also, two input power-sources can be integrated into a bigger power source via the dual energy-integration mechanism, thus resulting in twice the output energy and obtaining the necessary tractive power. A dynamic equation is therefore derived from this system to obtain the flow direction for the power source. Furthermore, dynamic equations of various system components can be established by the modularized software Matlab/simulink, and fuzzy logic is used to control and develop this system's dual energy-integration mechanism as a control strategy. It can be learnt from the system simulation that, after the engine's energy is distributed by the controller of the dual energy-integration mechanism, subjected to a deceleration ratio of the first pulley-set of the internal-combustion engine distribution mechanism and added to the generator torque transmitted from the second pulley-set, the engine can maintain an optimum state under various operating conditions.

This study adopts airflow management technology to improve the local temperature distributions in an automobile to counteract the greenhouse effect. The automobile's temperature can be reduced to almost the outside temperature before the driver or passenger gets into the vehicle. When the engine is idling, the greenhouse-control system can be activated to remove the hot air from the car. An appropriate negative pressure is maintained to prevent stuffiness and save energy. The greenhouse-control system requires electrical power when the engine is idle, and a battery cannot supply sufficient power. An auxiliary solar-power supply can save energy and reduce the greenhouse effect of sunlight, while creating a comfortable traveling environment. It ensures that the engine is not overburdened and increases its service life, conserving energy, protecting the environment and improving comfort.

Many complex technologies have been developed and applied to improve the energy efficiency and exhaust emission of an engine under different driving conditions. The overall thermal efficiency of an internal-combustion engine, however, can be maintained at only about 20–30%, with aggravated problems in the design and development, such as overall difficulty, excessive time consumption or excessively high cost. For electric cars, there is still no major technological breakthrough for the rapid recharging of a large capacity battery and detection of remaining power in it. Although all currently available hybrid-power engines are able to lower the amount of exhaust emissions and the fuel consumption of the engine, they are still unable to achieve a stable and optimal running condition immediately after ignition; hence the engine's thermal-efficiency remains low. To solve the aforementioned problems, an innovative concept – a hybrid pneumatic power-system (HPPS), which stores “flow work” instead of storing electrochemical energy of the battery – is introduced. This innovative power system not only ensures that the internal-combustion ensures optimally but also recycles the exhaust flow to propel the vehicle. The optimization of the internal-combustion and recycling of the exhaust energy can increase the vehicle's efficiency from an original 15% to 33%, an overall increase of 18%.

Improvements in engine-manufacturing technology have gradually increased the thermal efficiencies of engines as well as the burning temperature and pressure of fuels within the cylinders. Accordingly, greater heat dissipation are required. However, the volume of the radiators is constrained by the configuration of the engines, leading to excessive internal resistance in the engine-cooling system. Therefore, water pumps in engines are prone to cavitation, and air bubbles are likely to permeate into the anti-freeze, thereby severely reducing the performance, reliability and service life of the engines. Ethylene glycol (EG) is added to the radiator of some vehicles in cold areas to reduce the solidification point of the coolant and prevent freezing. This study probes the effects of the percentage of anti-freeze added to the cooling water in a water pump in an engine on the water-supply capability and cavitation temperature, whether air or burnt gas is present in the system. The results of this study have revealed that engines have a higher tolerance to air bubbles at lower rates of rotation. At a given fixed rotational speed, the tolerable cavitation temperature of an engine's water pump will fall slowly as the amount of air bubbles increases.

This new system promises an internal-combustion engine that always maintains optimal operating conditions. The system comprises two parts: (1) an internal-combustion power-distribution device and (2) an integrated design involving the engine and electronic motor. The internal-combustion power-distribution device provides an engine capable of constantly operating in an optimal fashion, minimizing emissions and maximizing thermal-efficiency. The electric motor can generate extra power. Notably, the integrated torque design comprises three helical gears. This design can release the power of the engine or electric motor separately, or can integrate these two different powers into a hybridized power system.