Baltic Blender

Gasblending for technical diving

Technical diving gas partial-pressure blending app. Supports nitrox and - via in-app purchase upgrades - trimix and pricing/volumes used.

Baltic Blender uses the GERG-2004 real gas model to allow a SCUBA gas blender to easily and accurately use partial-pressure techniques to blend available gasses to the desired final mixture. It is not intended as a substitute for proper training and certification in the safety, handling, and blending of high pressure gasses, but rather as a tool to perform the complex math required to reach the desired mixture. In such training classes, you would learn important safety information about the handling of high-pressure gasses. SCUBA gas blending is not to be taken lightly; it is one of the only activities where a mistake may not just kill you, but also those around you, or possibly the diver you are blending the gas for.

Traditional blending techniques have two inherent errors which the blender must learn to compensate for, traditionally by adding a fudge-factor. First, traditional blending uses the simple ideal gas model, but the gasses we breathe, at SCUBA cylinder pressures, are far from ideal gasses. Baltic Blender uses the GERG-2004 real gas model which predicts how the real-world gasses behave. Second, traditional blending generally ignores the heating of the cylinder as gas is introduced, requiring the blender to either fudge or allow the cylinder to cool. Baltic Blender requires that the blender allow the temperature to stabilize, rather than cool, between each step, so that an accurate measurement of the cylinder wall temperature using a commercially available infrared thermometer reflects the temperature of the gas inside.

Supports using preblended gas for eg. using leftover trimix or for using banked mixes.

Features ;

• Nitrox
• Trimix (via in-app purchase)
• Volume consumed & Pricing (via in-app purchase)
• Blending and topping off
• Metric and imperial units.
• Simultaneous work on multiple cylinders
• Grouping of tanks and pricing
• Real Gas Law using GERG-2004
• Per cylinder configurable preblend
• Easy to access temperature adjustments
• Configurable list of default gases
• Configurable standard temperature
• Bill printing/emailing

You can enter the data for multiple cylinders at once. Cylinders can be placed in groups for billing purposes.

** Trimix, volume consumed and pricing is only available via in-app purchase upgrades. **

GERG-2004; Kunz, O.; Klimeck, R.; Wagner, W.; Jaeschke, M. (2007): The GERG-2004 Wide-Range Equation of State for Natural Gases and Other Mixtures: GERG Technical Monograph 15 (2007) and Fortschr.-Ber. VDI, Reihe 6, Nr. 557, VDI Verlag, Düsseldorf, 2007.

The partial GERG-2004 implementation used to calculate the compressibility factors of oxygen, helium, nitrogen and their mixtures in the gas phase was inspired by open source code written by David de Marneffe (daviddemarneffe[at]y a h o o . c o m) in December 2007.