Patent ID: 7222058
Filing Date: 2007-05-22
Classification: G05B

Abstract:
1. A method of determining a size of a heat exchanger for a chosen application using a computer spreadsheet, the method comprising: a) identifying a heat exchanger; b) acquiring a plurality of heat exchanger parameters for the heat exchanger; c) assigning input temperatures, the input temperatures comprising a hot water input temperature and a cold water input temperature; d) assigning a first set of flow rates, the first set of flow rates comprising a first hot water flow rate and a first cold water flow rate; e) inputting the first set of flow rates, the input temperatures, and a set of assumed output temperatures into a set of equations arranged in a computer spreadsheet to obtain a heat transfer coefficient, the set of assumed output temperatures comprising a hot water output temperature and a cold water output temperature, and calculating a first heat transfer coefficient with the computer spreadsheet; f) inputting the heat exchanger parameters, the first set of flow rates, the first heat transfer coefficient, and the input temperatures into a set of equations arranged to calculate a set of output temperatures in the computer spreadsheet, the output temperatures comprising a first hot water output temperature and a first cold water output temperature, and calculating the set of output temperatures with the computer spreadsheet; g) inputting the set of output temperatures into the set of equations arranged to calculate the heat transfer coefficient, and calculating a second heat transfer coefficient; h) inputting the second heat transfer coefficient value into the set of equations arranged to calculate the set of output temperatures, and calculating a revised set of output temperatures with the computer spreadsheet; and i) calculating a first variance between the set of output temperatures and the revised set of output temperatures with the computer spreadsheet; j) assigning the revised set of output temperatures as the set of output temperatures; k) repeating steps g) through j) until the variance is less than 0.1 degree F., and l) outputting the revised set of output temperatures to an output device,