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Cequel

 

CequelTM

Chemical Equilibrium in Excel®

Plot of Isp as a function of O/F and Area Ratio

©2003 by Software and Engineering Associates, Inc. All rights reserved.

Introduction

CequelTM is an Excel® Add-In chemical combustion analysis tool for assessing the products of combustion under equilibrium conditions using the minimization of the Gibbs free energy. The NASA Lewis chemical equilibrium computer program is the underlying solver.

CequelTM provides four major comprehensive applications:

CequelTM solves for products of combustion at chemical equilibrium using the minimization of the Gibbs free energy (as opposed to the maximization of entropy), which is the equivalent of finding the point where the maximum net work obtainable has been extracted from the system. The underlying solver is based upon the NASA Lewis chemical equilibrium computer program. The NASA Lewis program is an Aerospace industry standard for the prediction of propulsion system performance. To aid in the analysis of a wide range of combustion problems, Cequel's extensive thermochemical database contains over 1000 chemical species and elements (including ions). CequelTM also features a reactants / ingredients library that contains over 60 common fuels and oxidizers.

You can easily generate and print graphs and files within Microsoft Excel®. (All of the art and examples used in this brochure were captured directly from CequelTM.)

 

Chemical Equilibrium

Chemical equilibrium is the classic limit case of all combustion processes. As with all equilibrium processes, it represents a balance between competing mechanisms. When a system is in chemical equilibrium, the chemical reactions for production and destruction of species are occurring at an equal rate, so that the concentrations of the reacting substances do not change with time. In terms of thermodynamics, chemical equilibrium is the condition in which there is no tendency or potential to make the composition of the system change; that is, no change can occur in the system without outside work being done on the system. While there are several approaches to solving systems in chemical equilibrium, the thermodynamic approach has proven to be more powerful for general chemical systems.

 

General Operation

CequelTM contains both a spreadsheet function and wizards help the user insert an instance of the function into the spreadsheet for a specific application. The first section of both the function and the wizard allows you to select the problem type, the ingredients that are to be combusted, and the relative amounts of each ingredient. Specification of the mixture ratio(s) can be in terms of O/F, equivalence ratio, Fuel %, or Air/Fuel ratio. A tri-propellant option is also available. The second section is problem specific, allowing the user to select equilibrium properties and products.

Hardware/Software Requirements


Pricing

Computer-locked Licenses:

Floating Licenses:


SEA LogoSoftware and Engineering Associates, Inc.

1802 North Carson Street, Suite 200
Carson City, NV 89701
(775) 882-1966 / (775) 882-1827 (FAX)

CequelTM is a trademark of Software and Engineering Associates. Inc.
Windows®,, Office® and Excel® is a registered trademark of Microsoft Corp.

 

Approval from the U.S. Department of State Office of Defense Trade Controls must be obtained before any of SEA's codes can be exported.

This approval process typically takes 90 to 120 days.

For more information, please contact us at info@seainc.com

(c) 2003 Software and Engineering Associates