StemFox Scientific Calculator vs ResToolbox3

Become a better engineer! Stop wasting your time on pointless busy work! Complete your calculations more quickly and accurately. Designed by an engineer, for engineers, StemFox has all the tools you need: Calculator STEM homework is technical and demanding. Accordingly, StemFox includes a calculator able to handle the most complex equations. From trigonometry to Bessel functions, StemFox has you covered! ･More than 80 mathematical functions. ･Quick reference to common basic scientific functions and operators. ･Quickly and easily copy and paste values. ･Quickly reference calculations in all parts of the app. ･Reference previous calculations via the ans(x) method. ･Prettyprint formatting of calculations. Textbook Companions Homework is an important portion of education. Entering equations into your calculator is not. Yet, this tedious error prone activity takes up a significant portion of homework time. Enter StemFox Textbook Companions. Textbook Companions contain references to a textbook’s equations and tables. Equations: ･Equations are referenced by number and name/description. ･Equations are searchable and divided into chapters for quick reference. ･Equations are solvable for any variable. Enter the known variables, and solve for the unknown one. ･Avoid error prone calculator entry. ･Avoid the errors and tedium of entering variables multiple times in the same equation. ･Decreases calculation time by as much as 90% over entering the entire formula yourself! Tables: ･Quickly lookup table values. ･Fast, easy, accurate, table linear interpolation. ･Copy and paste values with a simple tap, no transcription errors! Yay! Unit Converter Unit conversion is a common STEM activity. To speed up this irritating activity, StemFox offers the most comprehensive scientific unit converter available! ･More than two dozen separate units and nearly 300 individual conversions available. ･Tap to copy, tap to paste. Terms of Use: http://stemfox.io/index.php/eula/ Privacy Policy: http://stemfox.io/index.php/privacy-policy/

ResToolbox3 is a petroleum engineering calculator built for engineers who need answers fast - on a rig floor, in a meeting, or on a plane. PVT analysis, nodal analysis, gas hydrate prediction, production forecasting, volumetric calculations, and well testing, all from your iPhone or iPad. FLUID PROPERTIES (PVT) - Gas PVT: Z-factor, viscosity, compressibility, pseudo-pressure, water content, and thermal properties via 5-component Peng-Robinson EOS. Handles CO2, H2S, N2, H2, and hydrocarbon mixtures including pure and high-concentration cases - Oil PVT: Bubble point, solution GOR, formation volume factor, viscosity, and compressibility using Valko-McCain and Velarde correlations. Three solve modes with scaling factors for GOR and viscosity - Brine & Rock: Soreide-Whitson mutual solubility with Spivey brine correlations. Gas composition from Gas PVT flows through automatically GAS HYDRATES - Hydrate formation prediction via Motiee and Towler-Mokhatab correlations - Thermodynamic inhibitor dosing for MEG, DEG, TEG, methanol, and ethanol - Interactive P-T stability curves with inhibited and uninhibited envelopes - Water content mass balance between reservoir and operating conditions NODAL ANALYSIS - Gas and oil well inflow performance (IPR) with non-Darcy flow and Vogel - Outflow performance (VLP) via four methods: Woldesemayat-Ghajar, Hagedorn-Brown, Beggs & Brill, and Gray - 3x3 sensitivity matrix or real-time Explorer mode with interactive sliders - Water cut modelling with physics-based two-phase flow - Injection well support PRODUCTION FORECASTING - Single-well decline profiles: hyperbolic, exponential, and harmonic - Two-stage decline with continuous slope matching - Multi-well field development with drilling schedule, plateau constraints, and abandonment rate VOLUMETRICS - Deterministic OGIP and OOIP with combined gas/oil mode - Monte Carlo probabilistic analysis with Normal, Log-Normal, and Triangular distributions - Exceedance probability curves with P90, P50, and P10 reporting WELL TEST & TOOLS - Choke flow: gas mode (Gilbert, Norsok, TAM, SLB) and oil mode (Gilbert, Ros, Baxendell, Achong) - AGA-3 orifice metering for gas and ISO 5167 for liquid - Gas flowline pressure drop: 30-segment Darcy-Weisbach with PR-EOS properties at each segment, plus Weymouth and Panhandle B empirical methods - Petrophysics: Archie equation with density, sonic, and direct porosity methods, Pickett plot - Gas heating value and composition - Pipe capacities database (tubing, casing, drill pipe) - Unit converter with HC equivalents, reciprocal GOR/CGR, and density-gradient conversions DESIGNED FOR THE FIELD - iPhone-first interface with iPad responsive layouts - Oilfield and Metric unit systems with one-tap toggle - Share results and charts via email or messaging - Available in English, Norwegian, French, Chinese, Spanish, and Arabic - Works fully offline - no internet connection required - PVT properties flow between modules automatically All calculations use published, peer-reviewed methods from SPE literature and industry-standard references. No proprietary correlations, no curve-fitted shortcuts. Tabular data exports let you paste results directly into Excel or Google Sheets.