# Welcome to Neutrium

Neutrium is a knowledge base of engineering topics, centred mainly around chemical engineering design challenges faced by engineers in their daily work. We created Neutrium to bridge the gap between theory and practice. Feel free to ask a question, leave feedback or take a look at one of our in-depth articles.

As fluid flows through a packed bed it experiences a pressure loss due to friction. This article describes the use of the Carman-Kozeny and Ergun equations for the calculation of pressure drop through a randomly packed bed of spheres.

Birmingham Wire Gauge (BWG), also known as Stubs Iron Wire Gauge is a system of measurements describing thickness. BWG has been historically used to describe the outside diameter of small tubes and wires, as well as the wall thickness of some large tubes (such as those used within a shell and tube heat exchanger). This article presents length conversions for BWG values into metric and imperial units.

There are many operations in which two phases must be separated. These separations may be gas-liquid, gas-solid, liquid-liquid or liquid-solid, with several factors such as relative densities, gravity, fluid velocities and the shape of particles and/or droplets influence the phase separability. In this article we present the fundamentals of these separations and provide the Stoke's, Intermediate and Newton's formulae for calculating the terminal velocities of settling particles to analyse separation systems.

Nominal Pipe Size (NPS) is a defined set of standard pipe sizes commonly used for process piping. NPS piping is defined in terms of a nominal diameter and wall thickness (defined by the pipe schedule). This article provides characteristics for NPS piping in metric units.

Nominal Pipe Size (NPS) is a defined set of standard pipe sizes commonly used for process piping. NPS piping is defined in terms of a nominal diameter and wall thickness (defined by the pipe schedule). This article provides characteristics for NPS piping in Imperial units.

The calculation of a horizontal vessels wetted area and volume is required for engineering tasks such fire studies and the determination of level alarms and control set points. However the calculation of these parameters is complicated by the geometry of the vessel, particularly the heads. This article details formulae for calculating the wetted area and volume of these vessels for various types of curved ends including: hemispherical, torispherical, semi-ellipsoidal and bumped ends.

When a fluid moves from a tank or vessel into a pipe system or vice versa there are pressure losses. This article provides K-values for pipe entrances and exits of various geometries. These K-values may be used to determine the pressure loss from a fluid flowing through these entrances and exits.

A blackbody is an idealized volume which emits and absorbs the maximum possible amount of radiation at a given temperature in all directions over a wide range of wavelengths. Blackbodies are perfect emitters and absorbers of radiation and therefore useful as a standard when studying radiative heat transfer systems where the amount of radiation emitted and absorbed is a also a function of material properties. This article describes the basics of a black body and presents equations to describe its emissive characteristics.

This article provides methods to calculate the K-value (Resistance Coefficient) for determining the pressure loss cause by changes in the area of a fluid flow path. These types of pressure drops are highly dependent on the geometry and are not usually covered in simple pressure loss estimation schemes (such as a single k-value, equivalent length etc.)

Fittings such as elbows, tees, valves and reducers represent a significant component of the pressure loss in most pipe systems. This article details the calculation of pressure losses through pipe fittings and some minor equipment using the 3K method.