TABLE OF CONTENTS Here at the end lies a potpourri of (hopefully) useful design techniques.
All electrical engineers know Ohm s law, V = IR: that a current flows through a resistor, and that the current is forced by an electrical pressure, or voltage. The constant of proportionality between voltage and current is the circuit resistance R, in ohms. Given that we all accept Ohm s law, analogies may be made with other physical systems in an attempt to generate simple models for complicated physical processes.
With a little thought, the flow of current in a resistor may be compared to flow of water through a pipe, where current is analogous to water flow rate, and voltage is analogous to the pressure differential across the pipe that forces the water to flow. The resistance to flow is dependent on the diameter of the pipe, its length, the viscosity of the fluid, and other parameters.
With a little more thought, heat flow can be modeled with simple circuit analogies. A warm body may be heated or cooled by three mechanisms: conduction, convection, and radiation. Conduction is transfer of energy when heat is transferred by a solid; for instance, heat (in watts) is transferred down a water pipe when heat is transferred down the pipe body from a warm indoors to a cold outdoors. Convection is heat transfer due to moving fluid or air (for instance, blowing on a hot bowl of soup to cool it off). Radiation is an...
