Investigation of Oil - Water Ultrasound Emulsifier

Diesel fuel and water emulsifier designed for diesel fuel contaminated with water mixing to improve fuel combustion properties, it could also be used as mixing device for water and diesel fuel mixture. Examined literature describing the oil and water mixture emulsifiers. Analyzed the experiments related to diesel fuel and water emulsion combustion and distribution of its water volume. It has been developed and described principle emulsifier scheme. Calculated and modeled piezoelectric ultrasonic vibration actuator, which causes cavitations in mixing chamber. Ultrasonic vibration actuator is designed for the cavitation emulsion processing. Comparing experimental data with calculations obtained less than 10% deviation from the theoretical resonance frequency values. Performed experimental testing of ultrasonic vibration actuator to determine its resonance values. It also performed test of the distribution of water drops in diesel fuel using a microscope. Diesel fuel combustion effluents is one of the major problems stopping air pollution, especially in more populated areas

Principles for design of washing-machines with low vibro-activity

The paper presents the study of dynamics of rotor machines. The investigation is performed on the basis of linear theory of vibrations with application of the proposed analytical model to a specific case of washing - machines. Basic requirements have been defined for the design of the machines that enable reduction of their vibro-activity

Selection of number of gaps in superimposed moiré measurements

Plane vibrations of a two dimensional elastic structure are investigated in this paper. Vibrations taking place according to the eigenmode are represented by using the method of stroboscopic geometric moiré. Selection of number of gaps when using the superimposed moiré technique is investigated and recommendations for choosing of their number are provided

Measurement of plane vibrations of a two dimensional elastic structure

Plane vibrations of a two dimensional elastic structure are analyzed in this paper. The vibrations taking place according to the eigenmode are represented by using the method of stroboscopic geometric moiré. This requires to perform the investigation for two mutually perpendicular directions of moiré fringes. Here the superimposed moiré technique is proposed to represent both images at the same time

Piecewise constant control of a precise measurement platform

Control of a precise measurement platform is investigated in this paper. Piecewise constant control procedure on the basis of finite element in time and the method of least squares is proposed. It is demonstrated that the proposed technique can be used to follow not only a predetermined law of displacement variations, but also velocity variations. Computational experiments with a system comprising one degree of freedom are used to illustrate the efficiency of the proposed technique

Measurement of large amplitude plane vibrations of two dimensional structures

In the paper large amplitude plane vibrations of an elastic structure are investigated experimentally by using the method of time averaged geometric moiré. Investigations of a two-dimensional problem are performed. Experimental setup is developed and the results obtained by using the experimental procedure are analyzed. On the basis of a one-dimensional model graphical relationships for linear variation with respect to longitudinal coordinate of amplitude of vibrations are obtained. They provide the background for interpretation of partially exposed time averaged moiré. Recommendations for the choice of background intensity are provided

Investigation of elliptical approximation in the model of the force of dry friction

In the numerical procedures involving the force of dry friction some type of numerical approximation for this investigated phenomenon is used in the process of calculations. Elliptic approximations for the local transition region are proposed, and numerical results are presented in this paper. The smoothness and continuity of this approximation is demonstrated by several computational experiments

The effect of fuel additive SO-2E on diesel engine performance when operating on diesel fuel and shale oil

The purpose of this research is to perform comparative analysis of the effect of fuel additive SO-2E on the economical and ecological parameters of a direct-injection Diesel engine, operating on Diesel fuel and shale oil alternately. It was proved that multifunctional fuel additive SO-2E applied in proportion 0,2 vol is more effective for improving combustion of shale oil than Diesel fuel. At light operation range the treated shale oil savings based upon fuel energy content throughout wide speed range 1400–2000 min–1 reduce from 14,6–12,3MJ/kWh to 11,6–11,8 MJ/kWh or by 20,5–4,1 %. Maximum NO emission for treated Diesel fuel was reduced by 7,8–11,8 %, whereas NO2 simultaneously increased by 3,8–7,4 %. In the case of treated shale oil both harmful pollutants were reduced by 22,9–28,6 % and by 41,6–13,4 %, respectively. The exhaust gas opacity and CO emissions at the rated performance regime for both fuels were obtained a bit higher, whereas HC emission for treated shale oil increases 1,9 times and for Diesel fuel remains on the same level

The effect of rapeseed oil blending with ethanol on engine performance and exhaust emissions

The article presents the bench testing results of a four stroke, four cylinder, direct injection, unmodified, naturally aspirated diesel engine operating on neat rapeseed oil (RO) and its 2.5vol% (ERO2.5) and 7.5vol percent (ERO7.5) blends with ethanol. The purpose of the research was to investigate the effect of ethanol inclusion in the RO and preheating temperature on bio-fuel viscosity, engine brake power, specific fuel consumption, break thermal efficiency and emission composition changes, especially NO, NO2, NOx, CO, CO2, HC and smoke opacity of the exhausts. Inclusion in the RO 2.5 and 7.5vol% of ethanol the blend viscosity at ambient temperature of 20 centigrade diminishes by 9.2 and 28.3%. During operation under constant air-to-fuel equivalence ratio gamma = 1.6, blends ERO2.5 and ERO7.5 ensure the brake mean effective pressure (bmep) lower at the maximum torque 1800 min-1 by 0.5 and 2.3% (bmep=0.770 mpa) and at rated 2200 min1 speed by 2.4 and 9.1% (bmep=0.740 mpa), correspondingly, than that of neat RO case. The bsfc at maximum torque (248.7 g/kwh) and rated power (247.5 g/kwh) for blends ERO2.5 and ERO7.5 is higher by 1.3-4.4% and 4.2-10.7% and the brake thermal efficiency lower by 0.5-1.5% and 3.3-7.6%, respectively. The tests revealed that during operation of the fully loaded engine at rated 2200 min-1 speed, ethanol inclusion in the RO up to 7.5vol% diminishes NO, nox, HC, CO2 emissions, smoke opacity and temperature of the exhausts however it may increase simultaneously NO2, NO2/NOx and CO emissions