EXP 1-1 Description

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Front Page

Introduction

Review of experimental studies

Description

Experimental Set Up

Measurement Quantities and Techniques

Data Quality and Accuracy

Measurement Data and Results

Description of Study Test Case

The conical liquid sheet produced by water spraying from a PSA was investigated in cross-flow of non-heated, non-pressurised air. See Figure 1b, which shows the atomizer in the test section. The atomizer was operated continuously in cold-flow (non-reacting) conditions. It generated a water spray at inlet pressure, $p_{\text{in}}$, of 0.5 MPa. The flow conditions of the atomizer are described by Reynolds number:

$Re_{\text{in}}=\rho _{\text{in}}u_{\text{in}}D_{\text{in}}/\mu$

 

 

 

 

(14)

where $\rho _{l}$ is the liquid density, $u_{\text{in}}=Q_{\text{l}}/A_{\text{in}}$ is the liquid velocity at inlet ports and $D_{\text{in}}={\sqrt {4A_{\text{in}}/\pi }}$ is the hydraulic diameter of the inlet ports (for atomizer details see Figure 7 and corresponding text in section Experimental Set Up). The $Re_{\text{in}}=1330$. The presented case is one of three inlet pressure cases ($p_{\text{in }}=\mathrm {0} .25,0.5,1$ $\mathrm {MPa}$) measured and studied in . The interaction of the spray with the cross-flowing air is controlled by the ratio of the momentum of liquid to the air momentum, $q$ (see Equation 10) and by the Weber number which relies on the surface tension forces of the liquid film with the drag forces of the airflow, $We_{a}$ (Equation 11) or $We_{r}$ (Equation 12). $We$ and $q$ values for the experimental regimes are given in Table 2.

Table 2 Experimental regimes, basic characteristics of the flow and spray

$u_{cf}$ [m/s]	$p_{in}$ [MPa]	$Q_{l}$ [L/hour]	$C_{D}$ [–]	$We_{a}$ [–]	$We_{r}$ [–]	$q$ [–]
0	0.508	6.71	0.44	0.0	0.5	∞
8	0.498	6.72	0.43	0.5	0.85	3642.0
16	0.491	6.68	0.42	1.8	1.5	938.8
32	0.493	6.69	0.43	7.1	3.4	227.1

References

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Contributed by: Ondrej Cejpek, Milan Maly, Ondrej Hajek, Jan Jedelsky — Brno University of Technology

Front Page

Introduction

Review of experimental studies

Description

Experimental Set Up

Measurement Quantities and Techniques

Data Quality and Accuracy

Measurement Data and Results

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