Jenike Hopper Mass Flow Half-Angle Calculator
Determine critical hopper wall half-angle ($\theta_c$) for guaranteed mass flow discharge using Dr. Andrew Jenike bulk solids powder flowability theory.
Powder Internal & Wall Friction
Hopper Slope & Flow Regime
Mass Flow vs Funnel Flow (Jenike Theory)
In bulk powder storage, hoppers operate in one of two distinct flow regimes:
• Mass Flow: All material moves uniformly along the walls whenever any is withdrawn. Delivers First-In First-Out (FIFO) discharge, uniform density, and prevents caking, degradation, and segregation.
• Funnel Flow: Material flows only down a central vertical channel while stagnant boundary zones remain dead along the walls. Prone to catastrophic ratholing, flooding, and particle segregation.
Wedge / Chisel Hopper Advantage
In conical hoppers, powder converges in two horizontal planes simultaneously (circumferential hoop compression), demanding steep wall slopes ($68^\circ$ to $75^\circ$ from horizontal). Wedge hoppers with slotted rectangular outlets converge in only one dimension, allowing walls to be $10^\circ$ to $12^\circ$ flatter while still achieving true mass flow.