Numerical study of mechanically ventilated clean room

Dissertant

Ibrahim, Muntaha Hamid

University

University of Technology

Faculty

-

Department

Department of Computer Engineering

University Country

Iraq

Degree

Master

Degree Date

2004

English Abstract

A numerical study of a two-dimensional, turbulent, recirculating flow I with mechanically ventilated enclosure type clean room that contains a contamination source is presented.

The study is based on the solution of the elliptic partial differential equations representing conservation of mass, momentum, concentration, turbulence energy and its dissipation rate in finite volume form.

Algebraic expressions for the turbulent viscosity and diffusion coefficients are calculated using the two-equation model (k-e).

A computer program was built to simulate turbulent, two-dimensional, recirculating flow within an enclosure.

Different parameters are considered to illustrate their influences on the flow and diffusion fields.

These parameters include geometry of the rooms with different aspect ratios, exhaust inlet position, the level of air changes per hour (ACH) t / hour (The effect of air change, rates was evaluated by varying Reynolds number (Re) from 3.4 x 104-1.01 x 10" corresponding to supply outlet velocities u6 = 1.14-3.4 m / s) and position of the pollutant source.

The computed results were compared with experimental and predictions results of previous workers which were used as a test case to validate the performance of the present computational procedure.

It is concluded that the arrangement of the exhaust inlets rather small affects the entire flow field (unless short circuit occurs) for L / H ranging from (1 to 3) while it has a large influence on the contaminant diffusion field.

The larger the air changes rate, the larger is the area of low concentration.

The closest the pollutant source is to the exhaust inlet, the more efficiently it will be removed than the other models of contaminant source locations.

The detailed analyses of a flow field's contaminant diffusion field by simulation make it possible to comprehend clearly the structure of velocity and diffusion Field in clean room.

From examining of distribution of contaminant concentration, one can know which zone is dangerous because of highly contaminated air and where the contaminant remains unexhausted and where the contaminant is exhausted smoothly.

Main Subjects

Civil Engineering

Topics

• Buildings
• Aerodynamics

• APA
• MLA
• AMA

Language

English

Data Type

Arab Theses

Record ID

BIM-305880