Recent content by varnish

I am detecting detonation in a SI engine using a knock sensor (pizeo element). What I would really like is to have 3 leds that light up as the knock gets more severe. I have the knock sensor running into an op amp powered by a 9v battery. I am listening to the output with a pair of head...

Thank you for the reply mender. But I can't accept that engines will make more power towards stoichiometric than at a rich condition with the only factor being fuel mixing. The theory says that as you never reach the ideal otto cycle model due to dissociation of CO2 reducing the temperature in...

Hey guys, anyone want to jump in here? The information in this link gives some insight: http://www1.gantep.edu.tr/~ozcan/kitaplar/makina/term_%20heat/Advanced%20Thermodynamics%20for%20Engineers,%20First%20Edition/7699X_13.pdf The author [above] states: The author also states: The...

Hey guys, Combustion in an SI engine. So an AF:R of 14.7:1 is stoichiometric for petrol (gas), but an AF:R of 12.5:1 makes more power. One common thought is that not all the fuel and oxygen react in a stoichiometric mix, so by upping the fuel there is more chance of all the oxygen...

Hello I am struggling with how a compressor's efficiency is calculated. This is the set up: I have a Garrett T3 compressor housing being spun by an electric motor. I can measure the airflow in, the airflow out, the pressure and temperature on both sides of the compressor, the power...

Hi Bob, Could you explain that in layman terms please? If the stove does have triacs I suppose it would be possible to wire the element directly using a SSR to switch it.

I'd like to test somewhere around 5hp, so ~3.7KW Do you think a 4 hob stove (2*750W, 2*1500W) boiling water for cooling, and a few light bulbs ranging from 100w to 10W (or whatever I can get) would be a reasonable set up?

I suppose it would be possible to use a stove for coarse adjustment and bulbs for fine adjustment. I like the stove idea. Cooling could be provided by using a large sauce pan of water. I can imagine lots of light bulbs being a little unsafe. But is the idea okay? I realize it wouldn't be...

Hi guys. I'm interested in building a dyno to test modifications to small engines (lawnmower engines). I've found this old topic: https://www.physicsforums.com/showthread.php?t=117800 But I'm having some trouble picturing the design. I like the idea of using an electric motor and an...