The Department of Mechanical Engineering at the California Polytechnic State University, San Luis Obispo, has developed an innovative program of experimental research and development on hybrid rocket motors (where the fuel and the oxidizer are in different phases prior to combustion). One project currently underway involves the development of aerospike nozzles for such motors. These nozzles, ho...

Goal is to investigate how delivery nozzle design influences the cooling rate of cryogen spray as used in skin laser treatments. Cryogen was sprayed through nozzles that consist of metal tubes with either a narrow or wide diameter and two different lengths. Fast-flashlamp photography showed that the wide nozzles, in particular the long wide one, produced a cryogen jet (very small spray cone ang...

The Department of Mechanical Engineering at the California Polytechnic State University, San Luis Obispo, has developed an innovative program of experimental research and development on hybrid rocket motors (where the fuel and the oxidizer are in different phases prior to combustion). One project currently underway involves the development of aerospike nozzles for such motors. These nozzles, ho...

The lecture is given in four parts, each being a step in the process of nozzle design, and within each part the methods and techniques preferred by the lecturer are presented. We begin with a reminder concerning control volumes and the separation of aerodynamic and propulsive forces and moments. Then it is demonstrated how an appropriate control volume can help define the propulsive force vecto...

Control of jets has been studied for over a century and even today continues to be a significant research topic. It finds applications in various fields especially in aerospace, where enhancement of mixing characteristics of a jet can improve the performance greatly. Review articles by Gutmark et al.;1 Gutmark & Grinstein;2 Seiner et al.;3 Glezer & Amitay;4 Reynolds et al.;5 Ginevsky Vlasov & K...

Abstract—Liquid sprays of water are frequently used in air pollution control for gas cooling purposes and for gas cleaning. Twin-fluid nozzles with internal mixing are often used for these purposes because of the small size of the drops produced. In these nozzles the liquid is dispersed by compressed air or another pressurized gas. In high efficiency scrubbers for particle separation, several n...

0045-7930/$ see front matter 2009 Elsevier Ltd. A doi:10.1016/j.compfluid.2009.10.006 * Corresponding author. Tel./fax: +1 949 824 1750. E-mail address: [email protected] (F. Liu). The vortex dominated flows in the near field of jets from notched circular nozzles are investigated using direct numerical simulation. The nozzles studied include a normal circular nozzle, a V-shaped notched nozzle, and a...

Some of the major enhancements are eliminating head contention, reducing or eliminating nozzle changes, supporting user-defined nozzles, supporting large nozzles for holders 2 and 3, and being able to define multiple part data for a given part number. The cycle time improvement exceeds the original goal of 5%, and the result at one surface mount center was more than 16% over hand-created and op...

Abstract: In this paper, we establish existence of global subsonic and subsonic-sonic flows through infinitely long axially symmetric nozzles by combining variational method, various elliptic estimates and a compensated compactness method. More precisely, it is shown that there exist global subsonic flows in nozzles for incoming mass flux less than a critical value; moreover, uniformly subsonic...