# Search results

1. ### I Making a heat shield for my car's exhaust

Hello, I'm just wanting to make sure I remember this correctly. I have a hot exhaust pipe I want to shield from fuel lines. So I have a shield (stainless) that is going 1/2 way around the exhaust, with an air gap of about 1". I want to sand blast the side facing the heat and polish the side...
2. ### I Calculating the windspeed based on a brick being launched off of a closed dumpster lid

Hello, We had a wind storm. We have a dumpster with a lid. On that lid we put a heavy brick to keep the lid closed during wind storms. It's worked great for years. But we had a very strong wind storm and it launched that brick quite a distance. I'm trying to figure out the wind speed that would...
3. ### Calculating Temperature Change for Heat Exchanger

Hello, After the last post I completely changed the system. I now have a new system. Based on the feedback from last time I increased the time in contact with the block significantly. And I have made it a two stage unit. Here are the parameters for the first stage. An Aluminum block...
4. ### Need help with wiring motors in series and in parallel

Hello, I'm working on my kids ride on cars. He has two of them. On the first it was 6V and came with one motor on one wheel. I updated it to 2 motors, one on each wheel and 12Volts. I put in a DPDT switch so he could select high and low. On high the motors are run in parallel and on low they...
5. ### Rate of heat transfer/temperature change

Hello, I have another crazy project I'm working on and I need to know if this is viable before I spend a bunch of time and money. Here is the situation: I have a small block of Al. 1/4" x 1/4" x 1" long. Thru the length I drill a 1/16" hole. The surface will be whatever a standard drill bit...
6. ### Calculating temp change releasing a compressed gas

Hello, I understand when you release a compressed gas generally it comes out cooler than atmosphere. But here are my questions: When you fill the container, the gas warms up as the pressure builds. Generally it takes a long time to compress and I believe the temperature of the gas when it's...
7. ### How many BTU/hr needed to cool 500 CFM of air 100F degrees?

And does it matter if you are going from 200F to 100F or 500F to 400F? ie, is it temperature dependent? Thanks
8. ### Experiment to measure the thermal conductivity of a material

We have a customer asking us for the thermal conductivity of a product we sell. None of the engineers have that number. I can think of a simple experiment that might do it, but I don't know the math. I want to take a piece of this material (it's a pipe), put a cap on the bottom, then...