Location

Rolla, Missouri

Session Dates

11 Jun 1999 - 17 Jun 1999

Keywords and Phrases

Jet Fan; Tunnel; Ventilation; Model; Experimental

Abstract

The performance of a jet fan in a longitudinally ventilated tunnel is significantly reduced by the proximity of wall or ceiling where important shear stress losses occur. The paper focuses on the effect of jet fan inclination on the reduction of these losses; reducing losses means improved installation efficiency manifested by increased ventilation flow for the same fan power input. Experimental tests were carried out on a model at scale 1/5.5th. They allow one to determine the optimal jet pitch angle and the resulting benefit that could be drawn out of this solution in the case of tunnels with rectangular cross-sections. Also a few separation distances between the fan and the ceiling were investigated.

Department(s)

Mining Engineering

Meeting Name

8th U.S. Mine Ventilation Symposium

Publisher

University of Missouri--Rolla

Document Version

Final Version

Document Type

Article - Conference proceedings

File Type

text

Language

English

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Jun 11th, 12:00 AM Jun 17th, 12:00 AM

Improving the Ventilation Efficiency of Jet Fans in Longitudinally Ventilated Rectangular Ducts

Rolla, Missouri

The performance of a jet fan in a longitudinally ventilated tunnel is significantly reduced by the proximity of wall or ceiling where important shear stress losses occur. The paper focuses on the effect of jet fan inclination on the reduction of these losses; reducing losses means improved installation efficiency manifested by increased ventilation flow for the same fan power input. Experimental tests were carried out on a model at scale 1/5.5th. They allow one to determine the optimal jet pitch angle and the resulting benefit that could be drawn out of this solution in the case of tunnels with rectangular cross-sections. Also a few separation distances between the fan and the ceiling were investigated.