Napkin Diagrams

Engineering, Technology, and DIY

Monthly Archives: January 2010

Pressure Drops In Pipes: Part 2, Series and Parallel

This is Part 2 in a series on pressure drops in pipes. Part 1 covered the basic concepts and equations (1-4b). It is recommended to read that before proceeding, or to have it open along side this article for reference.

Symmetrical Parallel Pipes

Figure 1. Liquid flow branching into two symmetrical pathways before rejoining.

A single pipe is not usually sufficient to solve a real—life problem. Instead, systems of pipes, often quite complex, are used to achieve all desired results. The math, as a result, becomes more difficult, but where would be the fun if it was easy?
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Dream Job or Career Hell: Top 200 Job Ratings 2010

Now that the New Jersey Collegiate Career Day has come and gone, with opportunities in all manner of fields (although fewer presented for engineering that one would have hoped), it would be interesting to look at how people rank various positions. Have the once highly sought after careers retained their crown, or is the public opinion changing? A recent survey published by aims to shed some light on the matter.
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Pressure Drops In Pipes: Part 1, Basics

Stack of Pipes

A a fluid flows through a pipe, it will experience a natural pressure drop due to several factors. Friction is a major player, which itself involves flow velocity, pipe dimensions, and possibly internal pipe roughness. Height changes across the length of a pipe also contribute to pressure drops. Any and all fittings, coupling, et cetera will account for a part of any drops as well, although less so than the former two. Pressure drop can be related to head loss, a way of measuring the energy drop, with Equation 1, where ΔP is pressure drop, ρ is fluid density, g is gravity, and Δh is height difference.
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The Engineering Code of Ethics

Ethics play a major role in every engineer’s life. Being an application driven discipline, one in which people will deal directly with the end products and processes, following such a code is essential for safety and success. While obtaining a professional engineering license is a symbol of commitment to these ethics, and indeed to the highest standard in all aspects of engineering, it does not mean that the unlicensed are free to do as they wish. In fact, each particular field has their own established code that all must follow, from the recent grad to the senior member.
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2 Computers, 1… Speaker Set

Venn Diagram of Mac intersecting Windows with speakers
Computers and laptops have become cheaper and cheaper over the years. It has reached a point where it is not uncommon for a person to have more than one. Whatever the specific situation may be, the audio hardware setup will get a bit tricky. Computer speaker sets have only one input; unless one wants to shell out for multiple sets or a nice receiver system, the only solution is to continuously move the plug. For some, the access to all ports is easy enough that such a simple solution is sufficient. Most of the time, it would become irritating very quickly, especially if one has to alternate back and forth frequently. What is a man to do?
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