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A new energy recovery system based on scroll expander is presented according to the characteristics of low-grade energy in this paper. It is discussed for the expression of the system efficiency and its influential factors with the method of Exergy Analysis. And the influence curves of relationship between the expander’s inlet pressure and system efficiency are obtained through computer simulation and laboratory experiments. The test result of the comparison of different the recycling system shows that the recycling method based on scroll expander is more efficiently than others in the area of recycling low-grade energy.

It presents the compressor gas-cooler of a 300 MW Oxy-fuel pulverized coal fired boiler and established the simulation model of the cooler by the mechanism analysis method. On the simulation platform, the heat transfer performance and dehydration properties of cooler are studied on different pressure conditions. The simulated experiments show that when the flue gas inlet pressure is greater than the design pressure, with the increase of pressure, heat exchange performance of gas-cooler will declines; the water separation amount increases initially and then decreases subsequently.

The hydrodynamic cavitation degradation of chitosan with NaNO2enhancement was investigated. The effects of NaNO2dosage, temperature, inlet pressure, PH value, the concentration of the chitosan were been discussed. It was found that the hydrodynamic cavitation degradation of the chitosan can be largely enhanced by adding NaNO2. It was also seen that the extent of degradation chitosan can be changed marginally with the temperature.

The optimum inlet temperature for different engine conditions was calculated based on the same knock probability with full load by CFD Fire software, and then the effects of inlet air heated on combustion,pumping loss and emissions of gasoline engine were also studied. The results showed that the highest intake temperature at intake pressure 50kPa operation can be 368K without knock, and that for 100kPa condition was 322K. Heating inlet air can enhance combustion, and the maximum combustion pressure was increased by 26.8% and IMEP by 4% at the case of 368K/50kPa condition compared with inlet pressure of 40.5kPa and temperature of 298K condition consuming same fuel. Pumping loss can also be reduced by increasing intake temperature. However, emissions of NOXand CO were increased because of higher intake temperature.

In this paper, a preliminary exploration and research about the adaptive control law has been carried on for the turbofan engine with inlet pressure distortion. First, a real-time dynamic component-based model which contains the inlet distortion effects was established. Then, we select a single neuron PID controller with adaptive parameters to complete the dynamic acceleration process. The results illustrate that the single neuron control algorithm with gain adaptive has strong robustness, self-learning and anti-jamming capability and the performance of a turbofan engine can be effectively improved by using the turbine expansion ratio adaptive control law.

Aiming at characteristics of wire rope for stringing, this text designed mechanical structure of compressed air dehumidifying device, in order to study the influence of relative angle between air knife and wire rope, jet distance and inlet pressure of air knife on blowing pressure, it designed orthogonal experiment, using Fluent to simulate flow field of air knife, then obtain the flow characteristic parameters. After analyzing simulation results, the article draws a conclusion of influence of every factor on blowing pressure and the optimal level combination, providing a basis for practical dehumidifying work.

In this current paper, the influence of system efficiency and system parameters for simple compressed energy storage system were studied. EES software is used to simulate the pressure of system and efficiency of compressors, expanders, and pump for getting the optimal parameters of system. The results show that: for the simple system, when the expander inlet pressure is 6000kPa and compressor outlet pressure is 4000kPa, the system efficiency could get the maximum, and it is 76.2%. It is a better way for improving the efficiency of compressor and expander than the pump for system performance.

To further study, mesoscopic percolation evolution of gas-containing coal on loading conditions, this paper uses a self-developed loading system in seepage experiments to study the permeability changes of gas-containing coal on loading conditions, and it conducts CT reconstruction scan experiments on some pressure points. The results show that the permeability of coal samples decreases with increasing axial pressure when the air inlet pressure and confining pressure remain constant. It can be drawn by observation of the coal pore three-dimensional reconstructed images that when axial pressure increases to a certain value as well as other stress conditions remain unchanged, continue to increase the axial compression, coal pores and fissures appear contraction and even close, and the permeability of coal gets a reduction.

Calculating navier-stokes equation to study oil film pressure characteristics of three oil wedge bearing by using CFD software. Studied how to the three oil wedge sliding bearing effect on rotor stability, and analyzing oil film pressure characteristics of three oil wedge sliding bearing and cylindrical bearing. The results showed that three oil wedge bearing is much more stable than the cylindrical bearing, it is more advantageous to the running rotor and unit at stable working than the cylindrical bearing in the same oil film thickness and inlet pressure.

This study presents an energetic performance analysis for a waste heat produces electrical power system which is use organic Rankine cycle (ORC) from steelworks. In order to simulate the system under steady-state conditions, a mathematical model is developed. The developed model is used to determine the potential effects caused by the changes of the design parameters on the energetic performance of the system. As design parameters, turbine inlet pressure, condenser temperature, are taken into account. In this regard, the electrical power is estimated by parametrical analysis and discussed comprehensively.

To satisfy the demand of inlet pressure for air powered engine, it is necessarily to design control valve. The design idea of control valve was proposed, and the models for simulation design were established. These models are air bottle state model, open area model of control valve, spool dynamic model and shape calculation model of characteristic vent. Based on these models, the joint simulation and the experiment test have been done. The result shows that the designed control valve can provide required inlet pressure for air powered engine and satisfy the work demand well. The result of the experiment verifies the rationality and validity of the simulation design, and the method can be used in the design of the congener valve.

The purpose of this study is to examine the validity of groove in enhancing performance of splicing fiber in air splicer. A groove is usually used to improve the condition of internal flow, reduce the internal pressure and so on. In this paper, a two-parameter numerical mathematic model was developed and calculated in two configurations (chamber with groove and chamber without groove). The strength of the fibers was measured which were got from the air splicer with two different configuration. The result of simulation and experimental shows that: with the increase of inlet pressure, the rotational velocity and axial velocity of air flow also increase for the without groove case. As a counterpart, the axial velocity can be significantly reduced while rotational velocity keeps constantly for the groove case.

The purpose of this study is to examine the role of airflow on fiber’s strength under different inlet pressure. A two-parameter numerical mathematic model is developed to describe the airflow in splicing chamber. The simulations are validated against the experimental results regarding fiber’s strength. The flow field survey show that the swirling flow in chamber play a significant role in fiber’s splicing. The strength of splicing fiber is determined by two characteristics of flow, namely, vortices and pressure gradients which both were affected by inlet pressure. When the inlet pressure keep low, the strength of fiber is dominated by vortices of flow, otherwise, pressure gradients push fibers to wall quickly so fibers can not intermingle with each other completely.

Tubing plugging often occurs and brings some difficulties to industrial production. This paper proposes a simple pneumatic impactor which can instantaneously generate great acceleration by a reservoir to shock and smash calcium monohydrate bonding in the tubing inwall. The working principle and the mathematical model of the impactor are introduced in detail. In order to obtain its dynamic characteristic, the simulation is performed. The results show that during the movement of the piston back pressure occurs due to the outlet chamber squeezed by the piston with a high speed, and with inlet pressure increasing positions of the piston with different peak velocities are almost the same. This impactor can be used to unplug tubings in oil or gas well.

This paper analyzed the velocity field of the section between outlet orifice and the conical swirl chamber with a kind of single inlet pressure atomizer using CFD (Computational Fluid Dynamics) method. A method of modifying the outlet orifice position referring to the swirl chamber in order to improve the spray angle and its homogeneity is proposed. The result of the experiments shows that it is a feasible method to improve the quality of this kind of atomizer.

In layer-by-layer EDM milling based on inner jetted dielectric, the dielectric inlet pressure is an important process parameter and has great influence on the machining characteristics. So, numerical simulation of the liquid-solid two-phase flow field in discharge gap is conducted. The simulation results of debris concentration reveal that the debris can be evacuated from the discharge gap in time, which increases the machining process stabilization and improves the machining efficiency. Finally, the effect of dielectric inlet pressure on material removal rate (MRR) and tool wear ratio (TWR) were also researched and discussed. The optimum inlet pressure, which maximized the MRR and minimized the TWR, was found through experiment.