Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
Results
Showing 1 to 20 of 50 for “"Counterflow"”.
-
High pressure counterflow CHF.
This is a report of the experimental results of a program in countercurrent flow critical heat flux. These experiments were performed with Freon 113 at 200 psia in order to model a high pressure water system. An internally heated annulus was used to model a fuel pin in a channel. Only low flowrates …
-
Studies on counterflow diffusion flames
Certain aspects of counterflow diffusion flames are addressed in the context of one-step Arrhenius-type global chemical reaction. The general Large-activation-energy asymptotic theory for diffusion flames is first revised and then applied to one dimensional counterflow diffusion flames with finite …
-
Split-feed counterflow reverse osmosis for brine concentration
… In this thesis, a model is developed to simulate Counterflow Reverse Osmosis (CFRO), a membrane-based, pressure-driven brine concentration technology. Using this model, a single CFRO module is simulated and its performance characterized. Entropy generation within a single-stage system is analyzed, …
-
Novel Counterflow Reactor for Continuous Templated Synthesis of Semiconductor Nanocrystals
… utilizing a packed bed reactor operated in counterflow where the gas phase reactant enters from the bottom of the reactor while the microemulsion is fed from the top of the reactor causing a concentration gradient allowing for the most efficient and cost-effective use of the reactants. The …
-
Investigation on weakly curved counterflow diffusion flames at infinitely fast chemistry
We investigate the behavior of a counterflow diffusion flame subject to a flow field comprising of a first order potential flow superimposed on a weak second order correction to the potential flow. An Arrhenius one-step irreversible reaction model at infinite Damkohler number and constant density …
-
STUDY OF THREE-PHASE AIR-BRINE-SALT COUNTERFLOW IN AN INCLINED PIPE
Gas-liquid-solid counterflow (GLSCF) in inclined pipes occurs in various industrial processes, including oil and gas production and desalination systems. This thesis presents an experimental investigation of GLSCF in a 2-inch pipe inclined at 30°, utilizing air, saturated brine, and salt particles. …
-
Characterization of a 3D printed pumped counterflow virtual impactor and an aerodynamic lens concentrator
… pre-existing cloud sampling devices, the pumped counterflow virtual impactor (PCVI) and aerodynamic lens concentrator (ADL), were modelled using computer aided design software and printed using stereolithography printing. These devices were compared against their industrial counterparts. The …
-
Extinction strain rates of n-butanol, 2-butanol and iso-butanol in counterflow non-premixed flamelets
… iso-butanol) were studied experimentally in a counterflow burner, and computationally using a one-dimensional numerical model. The experimental results provided an insight in how the difference between molecular structures affects combustion of the isomers. Molecular branching made the isomers …
-
Thermal Analysis Based Design of Hollow Shaft for Improved Cooling of Induction Motors
… of the study. This includes the design of a counterflow, counterflow with fins, and duct design. It is found that third design is able to improve the temperature of the shaft while being manufacturable in a simple manner for future mass production. The heat transfer coefficient is also …
-
Modelling and Measurements on a Condensing Counter-Flow Heat Exchanger
… studies have been made on the refrigerant-water counterflow condenser section of a small air to water heat pump. The main object of the investigation was a comparative study between the computer modelling predictions and the experimental observations for a range of operating conditions but other …
-
Ozonation Systems as a Non-Chemical Alternative for Stored Grain Protection
… system and developing a semi-continuous counterflow and a continuous flow ozonation treatment system. The objectives of this research were to determine the efficacy of ozonation to control insect pests without affecting end-use quality; to prove the concept of the semi-continuous …
-
The phase separation inlet for droplets, ice residuals, and interstitial aerosols
… an omni-directional inlet, a Large-Pumped Counterflow Virtual Impactor (L-PCVI), a flow tube as evaporation chamber, and a Pumped Counterflow Virtual Impactor (PCVI) to separate droplets, ice crystals, and interstitial aerosols for simultaneous sampling. Verification tests of each …
-
Experimental and Theoretical Study of Hypergolic Solid Fuel Ignition and Combustion with Hydrogen Peroxide
… compositions and conditions. A modified RGHP counterflow spray experiment was introduced to investigate the ignition and combustion behaviors under realistic oxidizer flow conditions. The results demonstrated that while NaBH4 facilitated surface reactions, the reactions also caused structural …
-
Design, Fabrication, and Test of Chaotic Micromixers, Hydrogel Microvalves and pH Regulation Systems
… demonstrated. The first system is based on the counterflow microdialysis principle, whereas the second system involves direct addition of an acidic or basic buffer solution into a sample solution. In both systems, a hydrogel component is used as a pH sensor, controller, and valve, …
-
The effect of recuperator geometry on regenerated Brayton cycle
… respect to minimizing volume and weight for the counterflow plate-fin recuperator. Based on the Orenda OT-4 600 horsepower gas turbine, recuperator performance and dimensional characteristics are presented for an idealized equilateral plate-fin recuperator core matrix. The effects of plate …
-
Non-thermal plasmas in flames and other inhomogeneous environments
… gas. The experiments were then extended to a counterflow nonpremixed flame environment for which selective excitation of the flame was also observed. Such a strategy ensures that the plasma-created radicals and short-lived species participate in the combustion reactions, but it is achieved at …
-
An Experimental Investigation of JP-7 and n-Heptane Extinction Limits in an Opposed Jet Burner
… by the maximum global strain rate on a laminar, counterflow, non-premixed flame. The extinction limit relates to the ability to maintain combustor operation, and the extinction limit data for pure fuel versus air systems provide a relative reactivity scale for use in the design of flame holders. …
-
Modelling and computational analysis of heat-transfer in multi-geometry and multi-phase flow of Newtonian and non-Newtonian fluids in pipes and channels
… problems, the thesis will focus attention on counterflow heat exchangers in cylindrical geometries, specifically counterflow, double-cylinder heat-exchangers. The problem statement in this direction focuses on the non-isothermal dynamics and heat-transfer characteristics for a counterflow, …
-
The Role of Fuel Droplets in Laminar Flame Propagation
… and simulation. The twin premixed counterflow configuration was used to measure reference flame speed as a function of strain rate and nominal equivalence ratio (φ_0) for acetone/air mixtures. Two opposing stagnation flames were studied: a gaseous flame with prevaporised fuel, and a …
Page 1 of 3