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Fluids Equations
| Question | Answer |
|---|---|
| Bernoulli's | P + 0.5*p*v**2 + p*g*h = Ptot |
| Mass Flow | mdot = p*v*A |
| Cantilever Beam Stress | m*c/I |
| Cantilever Beam Deformation | F*L**3 / 3*E*I |
| Second Moment of Area | I, equations vary from shape to shape for squares b*h**3 / 12 |
| Conservation of Mass and Momentum | mdot*vi - mdot*vf = delta Momentumn = Pi*Ai - Pf*Af |
| Conservation of Energy | pf*hTf*vf*Af - pi*hTi*vi*Ai = dQ/dt + Wdot |
| Dynamic Pressure | 0.5*p*v**2 = q = gamma*p*M**2 /2 = kenetic energy per volume |
| Hydraulic Head | P/p*g + v**2 / 2*g + Z = Ptot/p*g = Head |
| H - Enthalpy | Total working energy in a fluid |
| Specific Heat | Need Youtube video |
| Speed of sound | a = sqrt(gamma*R*T) = sqrt(gamma*P/p) |
| Pressure and Density Relation in an ideal gas isentropic flow | P/p**gamma = const = P0/p0**gamma |
| Stagnation Temperature Ratio Relations | P/P0 = (p/p0)**gamma = (T/T0) ** (gamma/(gamma-1)) |
| Reynold's Number | p*v*D/mew |
| Laminar Flow | Re <= 2100 |
| Turbulent Flow | Re >= 2100 |
| RTT | dBsys/dt = dBCV/dt - Bin + Bout (B is any value) |
| Discharge Coefficient | Cd = mdot/(A*sqrt(2*p*(P2-P1))) |
| Flow Coefficient | Cv = Q*sqrt(SG/dP), SG- Specific Gravity for water is 1 |
| Area Mach Relation | dA/A = (M**2 - 1)dv/v |
| Pressure Loss in Laminar Flow (Darcy Weiback) | dP = f * (L/D) * 0.5*p*v**2 |
| Mass Spring Natural Frequency (massless spring) | w = sqrt(K/m)/2*pi (Hz) = sqrt(K/m) (rad/s) |
| Mass Spring Natural Frequency (Massive spring) | w = sqrt(K/m+ms/3)/2*pi |
| Work | Energy = int(fdx) |
| Spring Energy | Es = 1/2 kx**2 |
| Internal Energy | U = mCvT |
| Enthalpy | h = mCpT |
| Euler's Buckling Equation | n*pi**2 * E * I / L**2 |
| n in Euler's Buckling Equation | pinned-pinned: 1 pinned-fixed: 2 fixed-fixed: 4 fixed-free:0.25 |
| Torque Equation | T = I*alpha |
| Bolt Preload Equation | T = F*K*e(minor diameter) |
| Von Mises Stress Equation | sig = sq((sig1-sig2)^2 + (sig2-sig3)^2 + (sig3-sig1)^2) |
| Single Pin Shear | Tav(Average Shear Stress) = V/Apin T |
| Bolt Stress |