To improve engine power at high altitude, the regulated two-stage turbocharger (RTST) which was applied to different altitudes developed by authors. The working process model of heavy-duty common-rail diesel matched with RTST built study regulating characteristic variable geometry (VGT) vane and both turbine bypass valves also matching performance altitudes. control scheme operating conditions first put forward, optimal opening maps VGT were obtained. results show that openings decrease...

The engine performance test at altitudes of 0-7000 m was carried out on the high-performance bench Unmanned Aerial Vehicle (UAV) piston engine. flight UAV studied, including propeller thrust characteristics, maneuverability, envelope, and cruise performance. results showed that with increase in altitudes, climb rate gradually decreased; maximum decreased from 2.5 m/s 2000 to 0.5 7000 m. altitude is m, speed range about 47 m/s-52 Maximum navigation endurance decrease by 5.8% 8%, respectively,...

A variable geometry turbocharger in series with a (Twin-VGT) system was designed to improve engine power at high altitudes. The influence of altitudes on the performance Twin-VGT investigated perspective available exhaust energy. interaction between flow characteristics and openings vanes theoretically analyzed different Meanwhile, model diesel matched built study matching optimal opening maps both high-pressure low-pressure VGT were obtained achieve maximum power. results showed that...

Two-stage turbocharging technology is a solution to reduce turbo lag and improve the performance of engine matching characteristics at high altitudes. In present study, an testing system was established study combustion regulated two-stage (R2S) different simulated An equivalent turbocharger concept put forward aiming simplify R2S with three bypass valves, total turbine flow area efficiency were obtained based on theoretical study. Intake characteristics, process, torque, power fuel economy...

Aiming at the problem of power and economy reduction in high-altitude operation diesel engines, a radial basis function neural network-quantum genetic algorithm (RBFNN-QGA) optimization method is proposed to optimize engine dual-variable geometry turbocharger (VGT) regulated two-stage turbocharging (RTST) system. Firstly, GT-power simulation model dual-VGT RTST was established, then calibrated with test data. The latin hypercube sampling (LHS) selected for experimental design, back...

Measurements have been made on NaCl and KCl in water mixtures of with the four isomers butyl alcohol using following cell, which has no liquid junction consists ion-selective electrodes: cation(M); responsive glass or electrode [graphic ommitted]. The standard Gibbs free energies transfer from to were calculated cell potentials. This paper compares measurements ΔE°t G°t electrodes those obtained amalgam cells. results are reliable, differences between ΔG°t alcohol–water very small. is...

The in-cylinder gas flow is an important factor that affects the engine performance. appropriate swirl can reduce cycle-to-cycle variations, increase flame propagation speed, and improve combustion efficiency. Many technologies induce significant swirl, but lead to intake loss. In this research work, variable valve lift difference adjustment mechanism developed obtain adjust without weakening capacity in a four-valve gasoline engine. tumble characteristics generated by are studied means of...

In order to improve the plateau adaptability of CY4102BZLQ-A2A turbocharged diesel engine, matching performances engine with TB28 and HP60 turbochargers at different altitudes (0 m, 2,000 3,000 3,500 4,000 m) were investigated on test bed for simulating high altitude (1ow atmosphere pressure). Results show that HP 60 turbocharger is more suitable match in terms performance, intake air characteristics, rotational speed etc. over when runs m 2,600 r/min speed, while 2,800 speed. No matter...

本文应用振动管式密度计, 测定了278.15—318.15 K范围内10个温度下, DMF-H_2溶液的密度随组成的变化. 根据密度值求出溶液的超额体积VE; 在全部浓度的范围内不同组成下DMF的表观摩尔体积φv及偏摩尔体积V_(DMF); 及VE、φv和V_(DMF)随组成变化的规律. 发现V_(DMF)随x_(DMF)的变化与NaCl由水至DMF-H_2O溶液的转移熵有对应的变化规律, 均在x_(DMF)≈0.075处有极值, 从而进一步对DMF-H_2O的液体结构进行了讨论, 认为当x_(DMF)=0.075时, 单个DMF分子可能嵌入12个水分子组成的分子笼中, 从而形成最紧密结构。

Alternative fuel is an ideal solution to solve the problem of petroleum resources shortage and diesel engines' pollution. After analyzing China's energy structure merit demerit liquid alternative fuel, we finally find that F-T diesel-methanol-diesel-biodiesel blended best choice. The paper reviewed study home abroad from three aspects which contains miscibility physicochemical properties, spray characteristics chemical reaction mechanism. Finally, insufficiency development direction fuels...

It is significant to matching optimize of variable flow cooling system for diesel engine at high altitudes, which helpful enhance the power and economy, improve thermal efficiency, control heat load engine. The experimental design based on Latin hypercube sampling method was carried out, collaborative optimization parameters Genetic Algorithm (GA) established map fan speed water pump under condition altitudes (0 m ~ 5500 m) obtained, were coupled model system. Results indicated that as...

Aiming at the problem of complicated mechanism modeling for regulated two-stage turbocharging (RTST) system diesel engine, a hybrid genetic algorithm–particle swarm optimization (GA-PSO) method was applied to optimize back propagation neural network (BPNN) performance prediction model engine. First, using high-altitude (low-pressure) simulation test bench engines, full-load RTST engine different altitudes carried out, and regulation rules intake characteristics turbocharger (TST) matching...