Leith and Ellenbecker (1980b) use Equation 5.16(38) as the basis of a model to predict pressure drop across a pulsejet cleaned filter. Their model assumes that the fraction of the dust deposit removed by a cleaning pulse is proportional to the separation force applied and that impulse and conservation of momentum determine bag motion as follows:
where Kv depends on the pressure drop characteristics of the venturi at the top of each bag. Typically, Kv = 57500 Pa s2/m2. The value Ps is the pressure within the bag generated by the cleaning pulse, and it depends on venturi design as well as pulse pressure P as follows:
The values K1 and wo are from Equations 5.16(39) and 5.16(40), respectively. The term (K2/K3) is a constant that depends on the interaction of the dust and the fabric.
An environmental engineer can use Equation 5.16(46) to estimate the pressure drop of an existing filter when the operating conditions change. When the pressure drop under the initial operating conditions is known, the engineer can use Equation 5.16(46) to determine (K2/K3). Then, using this value of (K2/K3), the engineer can determine the pressure drop for other operating conditions.
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