scholarly journals Research on Blade Spin - type Pipe Mixer Design and PDPA Experiment

2017 ◽  
Keyword(s):  
Mixer Design

An alternative approach to evaluate fuel/air mixing quality

2021 ◽  
pp. 1-15
Author(s):  
L.-Y. Jiang
Keyword(s):  
Temperature Variation ◽  
Practical Method ◽  
Maximum Temperature ◽  
Air Distribution ◽  
Ratio Distribution ◽  
Alternative Approach ◽  
Low Emission ◽  
Mixing Quality ◽  
Mixer Design ◽  
Air Mixing

ABSTRACT A practical method to evaluate quantitatively the uniformity of fuel/air mixing is essential for research and development of advanced low-emission combustion systems. Typically, this is characterised by measuring an unmixedness parameter or a uniformity index. An alternative approach, based on the fuel/air equivalence ratio distribution, is proposed and demonstrated in a simple methane/air venturi mixer. This approach has two main advantages: it is correlated with the fuel/air mixture combustion temperature, and the maximum temperature variation caused by fuel/air non-uniformity can be estimated. Because of these, it can be used as a criterion to check fuel/air mixing quality, or as a target for fuel/air mixer design with acceptable maximum temperature variation. For the situations where the fuel/air distribution non-uniqueness issue becomes important for fuel/air mixing check or mixer design, an additional statistical supplementary criterion should also be used.

Simulation of Two Designs of Micro-Mixers With Enhanced Advection Mechanisms

2011 ◽  
Author(s):  
S. A. Kazemi ◽  
M. Passandideh-Fard ◽  
J. Esmaeelpanah
Keyword(s):  
Numerical Study ◽  
Control Volume ◽  
Numerical Technique ◽  
Chaotic Advection ◽  
Mixing Efficiency ◽  
Mixing Length ◽  
Surface Development ◽  
Mixer Design ◽  
Gas Liquid Flow ◽  
Micro Mixer

In this paper, a numerical study of two new designs of passive micro-mixers based on chaotic advection is presented. The advection phenomenon in a T-shaped micro-mixer is enhanced using a segmented gas-liquid flow; and a peripheral/axial mixing mechanism. The simulations are performed for two non-reactive miscible gases: oxygen and methanol. The numerical model employed for this study is based on the solution of the physical governing equations namely the continuity, momentum, species transport and an equation to track the free surface development. The equations are discretized using a control volume numerical technique. The distribution of the species concentration within the domain is calculated based on which a mixing intensity factor is introduced. This factor is then used as a criterion for the mixing length. In the first micro-mixer design with a drop injection mechanism for a typical condition, the mixing length is reduced by nearly 15%. Compared to that of a simple T-shaped micro-mixer with the same flow rates, the two gases interface area is increased in axisymmetric micro-mixer leading to an increase of the mixing efficiency and a reduction of the mixing length. Also, the effects of the baffles height and span on the mixing efficiency and length in axisymmetric micro-mixer are studied. Having baffles in the channel can substantially decrease the mixing length.

TECHNIQUES TO ENHANCE FLUID MICRO-MIXING AND CHAOTIC MICROMIXERS

2005 ◽  
Vol 19 (28n29) ◽  
pp. 1567-1570 ◽  
Author(s):  
Y. T. CHEW ◽  
H. M. XIA ◽  
C. SHU ◽  
S. Y. M. WAN
Keyword(s):  
Chaotic Advection ◽  
Chaotic Mixing ◽  
Inertial Effects ◽  
Passive Mixer ◽  
Poincaré Plot ◽  
Mixer Design ◽  
Recent Developments ◽  
Fast Development ◽  
Active Mixing ◽  
Working Mechanisms

With fast development of microfluidic systems, fluid micro-mixing becomes a very important issue. In this paper, recent developments on various micromixers and their working mechanisms are reviewed, including the external agitation methods applied in active mixing and the channel geometries adopted in passive mixer design. The chaotic mixing and the influences of Re would be mainly discussed. At moderate and high Re , the fluid inertial effects usually facilitate the chaotic mixing. At low Re , generation of chaotic advection becomes more difficult but can still be achieved through fluid manipulations such as stretching and folding. Chaotic mixers can be characterized using dynamical system techniques, such as Poincaré plot, and Lyapunov exponent.

Feasibility of Studying Fuel Mixer Design for High Power Engines Using Completely Biogas

2019 ◽  
Vol 889 ◽  
pp. 231-243
Author(s):  
Thanh Phong Tran ◽  
Quang Minh Nguyen ◽  
Quoc Cuong Tran
Keyword(s):  
High Power ◽  
Internal Combustion Engines ◽  
Combustion Products ◽  
Combustion Engines ◽  
Original Source ◽  
Power Generators ◽  
Crude Oil Prices ◽  
Mixer Design ◽  
Flour Production ◽  
Electronic Controller

Nowadays, the original source of mineral fuel for engines was depleting increasingly while combustion products make the environment to be polluted, CO2emission which caused many greenhouse gases; this also makes crude oil prices fluctuate and rise. They tend to use biogas as a fuel for internal combustion engines which have been interested in the powerful countries. Supply of biogas from the waste of farms, flour production, fish processing, landfills, etc., with hundreds or thousands of cube meter of biomass daily leads demand on high-power generators using biogas in order to make good use of produced gas. This article introduces a technology solution for fuel engines using purely large-capacity biogas and operating under compression type fire. Accordingly, the tubular biogas Venturi mixer with electronic controller has been used to supply the mixture of fuel to engine. The CDI-DC ignition circuit provides a high voltage of 28kV for forced combustion of the mixture. Experimental results show that the mixer operates stably, well controlled and allows adjusting the ratio of air/fuel, as well as easily changing its speed when it is used as a hybrid engine for the generator. Some results of performance evaluation of biogas mixer will be presented in this article.

Sign in / Sign up

Export Citation Format

Share Document