*[Page last edited 2017-04-08. Feed for postings in this category.]
*

I am an applied physicist and engineer by training. Today I am mainly interested in heat transfer, thermodynamics, energy storage, and power transmission. Here I curate the full lists of my physics posts; there is some overlap with the posts on heat pumps and renewable energy.

On an unrelated note, I am also / still interested in theoretical physics and I am self-studying or re-learning Quantum Field Theory and General Relativity.

[2017-04-08] **Mr. Bubble Was Confused. A Cliffhanger**. The very simple physics of temperature-dependent density caused some confusion – our automated level sensor underestimated the volume of ice in the melting phase.

[2017-02-22] **Ice Storage Hierarchy of Needs**. Mulling upon ‘Peak Ice’ in our heat pump system – and detailed simulations versus simple energy accounting.

[2017-01-07] **On Photovoltaic Generators and Scattering Cross Sections**. A physicist’s musings about the unit used to characterize solar panels’ peak power: kWp.

[2016-12-03] **Learning General Relativity**. Latest physics self-study project – my list of resources and why I picked them.

[2016-11-03] **And Now for Something Completely Different: Rotation Heat Pump!** An invention by an Austrian start-up that would make for an awesome example in physics and engineering thermodynamics textbooks: The pressure gradient is created by centrifugal forces!

[2016-09-18] **Re-Visiting Carnot’s Theorem.** From the theory department: Why can’t there be any heat pump / heat engine better than Carnot’s reversible machine? A closer look at the proof by contradiction.

[2016-03-01] **Rowboats, Laser Pulses, and Heat Energy (Boring Title: Dimensional Analysis)**. Re-visiting heat transport and heat diffusion length, this time only analyzing dimensional relationships. I introduce the concept of dimensional analysis by answering the question: How does the speed of a rowing boat depend in the number of rowers?

[2016-02-08] **No, You Cannot ‘Power Your Home’ by One Hour of Cycling Daily.** All the physics in this post is the relation of energy and power: kWh = kW times hours. Unfortunately it seems there is a need to harp on this.

[2016-01-22] **Temperature Waves and Geothermal Energy**. Solution of the Heat Equation, based on the simple assumption of a harmonically varying surface temperautre, plus a superimposed geothermal gradient. The results can be used for cross-checking the value of the thermal diffusivity of ground.

[2015-11-25] **Peter von Rittinger’s Steam Pump (AKA: The First Heat Pump)**. An account of the 19th century invention, based on the original German research reports.

[2015-09-29] **Heat Pump System Data: Three Seasons 2012 – 2015**. Brief summary of last season’s performance, plus back-of-the-envelope estimate of economics.

[2015-06-04] **Lest We Forget the Pioneer: Ottokar Tumlirz and His Early Demo of the Coriolis Effect.** Finally two science geeks did a careful experiment – proving that vortices on either hemisphere rotate in different directions. I just like to point to a pioneer who did such an experiment long before the social media era – in 1908.

[2015-06-01] **An Efficiency Greater Than 1?** The Coefficient of Performance of a heat pump is much greater than 1 which is due to the definition, omitting input ‘ambient energy’. The rather high factor gives proof of the fact that heat pumps operate well above absolute zero.

[2015-04-21] **How to Evaluate a Heat Pump’s Performance?** Definitions of performance indicators and how to determine them – comparing alternative methods, based on sensors available (Coefficient of Performance / Seasonal Performance Factor). Bonus: Cute math puzzle as the comparison boils down to: When is the ratio of averages equal to the average of ratios.

[2015-04-01] **Ice Storage Challenge: High Score!** The ice cube, generated by our heat pump, stopped growing at about 15m^{3}. About 10m^{3} of water remained unfrozen. Toying with theories and the differential equation of heat transport we came up with an explanation.

[2015-02-14] **A Sublime Transition**. Phase transitions between water, vapor, and ice: Last winter’s viral trend of freezing boiling water in mid-air, and discovering that scientists discuss such effects to this day.

[2015-01-28] **More Ice? Exploring Spacetime of Climate and Weather.** A simplified simulation based on historical weather data: A heat pump uses the sensible and latent heat in a tank of water and that energy is replenished using an unglazed solar collector: How large should this tank be so that it would hardly ever freeze completely in typical Eastern Austrian winters?

[2014-10-16] **All Kinds of Turbines**. Again some back-of-the-envelope cross-checks, this time related to hydro power.

[2014-10-04] **Pumped Heat from the Tunnel**. Cross-check of numbers for a large heat pump system, from a press release. The heat source is water from a tunnel.

[2014-06-22] **Grim Reaper Does a Back-of-the-Envelope Calculation**. Some crude estimates related to the physics of scything – and why it might be so exhausting.

[2014-02-16] **How to Introduce Special Relativity (Historical Detour): **An alternative way of understanding SR – found in my favorite ancient text book.

[2014-02-05] **Non-Linear Art. (Should Actually Be: Random Thoughts on Fluid Dynamics)**: Why is fluid dynamics hard? Where does that infamous non-linearity sneak in?

[2014-01-05] **In Praise of Textbooks with Tons of Formulas (or: The Joy of Firefighting).** Why I read theoretical physics textbooks in the morning.

[2013-12-22] **Student Friendly Quantum Field Theory**. Review of Robert Klauber’s excellent book.

[2013-12-02] **Using Social Media in Bursts. Is. Just. Normal**. On modelling the behavior of so-called intelligent life-forms using analogies from physics. Bonus: My anecdotal experience.

[2013-11-25] **Mastering Geometry is a Lost Art**. On Newton’s geometrical proof of Kepler’s laws.

[2013-11-15] **Revisiting the Enigma of the Intersecting Lines and That Pesky Triangle**. Following up on the puzzle – and correcting my earlier proposal. Epic comments!

[2013-11-04] **Learning Physics, Metaphors, and Quantum Fields.** A bit of path integrals and symmetries, introduced by lengthy ramblings on metaphors in physics.

[2013-10-17] **Hyper-Jelly – Again. Why We Need Hyperspace – Even in Politics**. Since my post on phase space was appreciated nearly only by physicists and mathematician, I have tried again – starting from a metaphor concerned with Austrian politics.

[2013-10-10] **On the Relation of Jurassic Park and Alien Jelly Flowing through Hyperspace. **I tried to explain Quantization using an uncalled for detour through phase space, pop-sci chaos theory memes and indulging in statistical mechanics.

[2013-09-29] **May the Force Field Be with You: Primer on Quantum Mechanics and Why We Need Quantum Field Theory** is a summary of what is popularized often, wave-particle etc., but I add some field theory at the end – and I start from a very down-to-earth field.

[2013-09-17]** Space Balls, Baywatch and the Geekiness of Classical Mechanics**. Why I believe that classical mechanics is as geeky as Quantum Theory – just view it through the lenses of an alternative, more spooky, mathematical representation.

[2013-09-11] **And Now for Something Completely Different: Quantum Fields!** The trailer of the series on Quantum Field Theory.

[2013-06-03] **Theory and Practice of Trying to Combine Physics with Anything **On the usefulness (or not) of models borrowed from physics in other fields.

[2013-04-03] **The Falling Slinky and Einstein’s Elevator**: It’s fascinating that it is not easy to explain seemingly mundane classical mechanics!

[2013-03-17] **The Twisted Garden Hose and the Myth of the Toilet Flush**: On Coriolis force.

[2013-03-13] **Intuition and the Magic of the Gyroscope** – Reloaded: It seems that *gyroscope* is one of the most searched for terms on this blog. I dish what you long for, readers!

[2013-02-09] **Physics / Math Puzzle: Where Is the Center of Mass?** An intriguing puzzle and my first (later corrected) proposal of a solution.

[2013-01-28] **Random Thoughts on Temperature and Intuition in Thermodynamics**: I could not resist to just let the hype about negative temperatures pass by.

[2013-01-06] **Why Fat Particles Radiate Less**: Thinking about the LHC – though some of my Facebook friends found better interpretations of this title.

[2012-12-30] **Quantum Field Theory or: It’s More Than a Marble Turned into a Wiggly Line.** A brief summary of the differences between Quantum Mechanics (think: Schrödinger’s Cat and Wave-Particle-Dualism) and why we need QFT.

[2012-12-05] **Is It Determinism if We Can Calculate Probabilities Exactly?** Quick primer on interpretations of quantum mechanics – and why I consider it problematic to use ‘philosophical terms’ in physics.

[2012-11-20] **Are We All Newtonians?** How intuition may fail us, even when dealing with alleged simple classical mechanics.

[2012-11-02] **Einstein and His Patents** … his refrigerator patent in particular.

[2012-10-23] **111 Years: A Shining Example of Sustainable Product Development?** I missed the most amazing light bulb’s birthday – the least thing I could do was to write a post.

[2012-10-04] **Physics Paradoxers and Outsiders**: My take on fringe science, inspired by Margaret Wertheim’s book Physics on the Fringe: Smoke Rings, Circlons, and Alternative Theories of Everything.

[2012-09-05] **The Spinning Gyroscope and Intuition in Physics**: Do we understand the gyroscope really? Marveling at Feynman’s explanation and new(!) papers on explaining it.

[2012-08-30] **Sniffing the Path (On the Fascination of Classical Mechanics) **Trying to demonstrate that classical mechanics is geekier than you think, borrowing terminology from Richard Feynman.

[2012-08-12] **Unification of Two Phenomena Well Known**: Electrical and magnetic fields are actually two aspects of the same thing (special relativity).

[2012-05-10] **Why Do Heat Pumps Pump Energy so Easily?** Brief (yes, really) explanation how a heat pump works.

[2012-04-29] **Stupid Questions and So-Called Intuition**: On learning physics.

[2012-03-28] **I neither Met Newton nor Einstein** Re: The Trouble with Physics by Lee Smolin.

[2012-03-25] **Real Physicists Do Not Read Popular Science Books** Are pop-sci books useful?