CFD ANALYSIS FOR DESIGN OPTIMIZATION OF REVERSE FLOW TYPE CYCLONE SEPARATOR: INTRODUCTION

INTRODUCTION

The cyclone separator is one of the most elegant pieces of engineering equipment. It is a device with no moving parts and virtually no maintenance. It enables particles of micrometers in size to be separated from a gas moving at about 15 m/s without excessive pressure-drop. Cyclone separators are very widely used throughout industry. Moreover, they can be found in all sizes and shapes. They can be used in some industries such as: Oil and gas, Power generation, Iron and steel industry, Cement plants, Coking plants, Coal fired boilers.

A full understanding of how the cyclone separator works and how individual particles behave within it is not yet available. Little information has been gathered until the invention of the measuring equipment necessary to measure fluid velocities within cyclones (laser Doppler anemometry – LDA). Ultimately, the development of computational fluid dynamics (CFD) codes could accurately model swirling flows within the cyclone.

A cyclone separator is a device, which causes centrifugal separation of materials in a fluid flow. Unlike the slow settling of particles within a settling tank, a cyclone separator system yields fast separation and utilizes less space. Separation occurs quickly because one ā€œgā€ of the gravitational force is replaced by multiple ā€œgā€ of the acting centrifugal force, the material to be separated can consist of solid particles or liquids, i.e. droplets, which are classified according to size, shape, and density. The cyclone utilizes the energy obtained from the fluid pressure gradient to create rotational fluid motion. This rotational motion causes the dispersed phase to separate relatively fast due to the strong acting forces. In widely used reverse flow cyclones of the cylinder on cone design type, gases spiral down from a tangential inlet towards the apex of a conical section, where the flow is reversed and the particles are collected in a hopper. The continuous phase then proceeds upward in an inner core flow towards the gas exit via the vortex finder. Cyclone designs have been developed over many years since their invention. Nowadays, there exist a large number of different types for various industrial applications. Many attempts have been made to improve the performance of cyclones by modifying their shape in terms of the ratio of different key dimensions. Normally, the continuous phase flow still carries some particles when it proceeds upward in the inner flow core towards the gas exit. Therefore, a solid apex cone has been incorporated in the cyclone to slow down the flow inside the dust collector (hopper).

Representative APR 391%. Average APR for this type of loans is 391%. Let's say you want to borrow $100 for two week. Lender can charge you $15 for borrowing $100 for two weeks. You will need to return $115 to the lender at the end of 2 weeks. The cost of the $100 loan is a $15 finance charge and an annual percentage rate of 391 percent. If you decide to roll over the loan for another two weeks, lender can charge you another $15. If you roll-over the loan three times, the finance charge would climb to $60 to borrow the $100.

Implications of Non-payment: Some lenders in our network may automatically roll over your existing loan for another two weeks if you don't pay back the loan on time. Fees for renewing the loan range from lender to lender. Most of the time these fees equal the fees you paid to get the initial payday loan. We ask lenders in our network to follow legal and ethical collection practices set by industry associations and government agencies. Non-payment of a payday loan might negatively effect your credit history.

Calculate APR