Part 1 examined a major technical problem of the 19th century: improving the efficiency and reach of the lighthouse beam, and why simply going “bigger” would not be possible. A new way of seeing the problem New ideas were needed, and the French government in the early 1800s was aware of the problem, even linking […]
The Fresnel lens: An obsolete innovation finds a 21st-century role – Part 1
Lighthouses may seem like quaint artifacts of a bygone era and now mostly used as tourist attractions, but as marine-based commerce expanded in the 18th and 19th centuries, they were indispensable for ship navigation and guidance to an extent we probably can’t imagine (this was before the gyrocompass, radar, and GPS world, of course). As […]
The hot wire anemometer, Part 2: Implementation
The hot wire anemometer for measuring fluid speed offers unique advantages but also has some challenging use issues. Part 1 looked at the basic principles of the hot wire anemometer. This part contains the discussion with issues related to calibration and practical concerns. As with so many other sensors, the HWA looks simple enough: It […]
The hot wire anemometer, Part 1: Principles
The hot wire anemometer for measuring fluid speed offers unique advantages but also has some challenging use issues. You are undoubtedly familiar with the classic wind-speed anemometer with three cups rotating as the wind blows, while a tachometer reports the revolutions rate (Figure 1). This is a “tried and true” way to measure large-scale wind […]
Coriolis flowmeter, Part 4: The future
The Coriolis effect, a subtle and often-misunderstood principle of physics, has been adapted for highly accurate mass flowmeter instrumentation. Due to their attractiveness as well as technology advances, Coriolis-based flowmeters are also evolving; also, the effect has been noted in other interesting areas. For example, while the tubes of the meter are usually bent, straight-tube […]
Coriolis flowmeters, Part 3: Flowmeter design
The Coriolis effect, a subtle and often-misunderstood principle of physics, has been adapted for highly accurate mass flowmeter instrumentation. The application of the Coriolis force offered a new way to solve the long-standing problem of measuring the flow of material. In 1977, Micro Motion Inc introduced the first standard industrial flow meter based on the […]
Coriolis flowmeters, Part 2: The principle
The Coriolis effect, a subtle and often-misunderstood principle of physics, has been adapted for highly accurate mass flowmeter instrumentation. The first part of this article briefly explained the issues associated with accurate measurement of fluid mass and flow, a very common requirement in industrial, laboratory, and medical applications. The Coriolis Effect, or “May the Effect […]
Coriolis flowmeters: A subtle global effect with local applications, Part 1: The challenge
The Coriolis effect, a subtle and often-misunderstood principle of physics, has been adapted for highly accurate mass flowmeter instrumentation. The Coriolis effect is generally viewed, if at all, as a “large-canvas” effect. It is yet another consequence of the rotation of the Earth, with many interesting implications such as the rotational direction of air masses […]
Heat shrink tubing, Part 2: Extensions
Although we take it for granted, versatile and widely used heat shrink tubing is the result of advanced material science, and is available in a broad range of varieties and options. Part 1 of this FAQ looked at the basics of HST and its history. This part looks at the many variations and standard options […]
The basics of heat shrink tubing, Part 1
Although we take it for granted, versatile and widely used heat shrink tubing is the result of advanced material science, and is available in a broad range of varieties and options. Along with duct tape ad nylon cable ties, heat shrink tubing is an essential element in the engineer’s toolkit as well as manufacturing, production, […]