Recent content by Cyphear

I haven't worked out the numbers, but one thing to think about is that relative humidity goes up with temperature drop, somewhere around 12% per 5C (9F). Absolute humidity is a better number to work with, but not one we normally reference. I haven't had a chance to work it out, but maybe after...

I found my use of Celsius (instead of Kelvin) a little confusing too. I'm not sure why I chose to define it at the top. You bring up a good point about my use of Fahrenheit. My numbers are all in Celsius, but I was thinking of them as Fahrenheit at the end. I'm going to edit my formula above...

Good point. I'm glad you found this thread and I'm glad I posted my math in the thread. Wow, this thread has almost 5k views. If I built an online calculator, I wonder if anyone would use it. I don't know where I got that formula either. In googling this, there are plenty of sources that...

That's some great information Russ. Those are also some pretty great links. I love me some thermodynamics! Since we have the A/C side of the equation figured out, I wonder if there is a formula for how heat enters a house on an average day. Some heat that enters would remain static in a...

I have heard that if they start breaking the speed of sound then you lose power. I'd copy a prop design that already exists. There's lots of info about this. Have you read any of this? http://www.google.com/search?q=propeller+design

Of course it's possible in theory to go faster than the speed of sound under water, but in practice its nowhere near possible for an animal to get going that fast. Simon Malzard, but then the water would be traveling, so the dolphin would just be inside water which is traveling faster than the...

Thanks for the reply Russ. I'll do some more research on the temperature drop and see if I can find some concrete numbers. Can you define "capacity" and "compressor energy goes up" in the second sentence? I'm guessing the later means that the compressor will use more power, but what is...

I have two questions/ideas about the efficiency of A/C's that I'd like to bounce off you guys. I couldn't find anything on Google about either of these items being discussed before. 1) Precooling The first thought I was wondering was whether it was more efficient to pre-cool your house in...