Heat transfer measurements for Stirling machine cylinders

摘要: The primary purpose of this study was to measure the effects inflow-produced heat turbulence on transfer in Stirling machine cylinders. A secondary provide new experimental information gas springs without inflow. apparatus for experiment consisted a varying-volume piston-cylinder space connected fixed volume by an orifice. orifice size could be varied adjust level turbulence, or plate removed completely so as merge two spaces into single spring space. Speed, cycle mean pressure, overall ratio, and varying clearance ratio also adjusted. Volume, pressure both spaces, local flux at locations were measured. measurements used calculate area averaged flux, hysteresis loss, other transfer-related effects. Experiments one arrangement extended range previous tests lower higher nondimensional speed. corroborated results showed that analytic models loss based approaching 1 valid ratios ranging from 2, covering most machines. Data experiments first analyzed lumping together examining total function parameter. Heat found significantly increased turbulence. These increases modeled appropriate adjustment empirical coefficients existing semi-analytic model. An attempt made use inverse, parameter optimization procedure find each spaces. This successful retrieving simulated pressure-volume data with artificially generated noise, but it failed actual data. is evidence (and generate data) not correct. surface sensors indicated shortcoming these they assumed levels constant over cycle. Sensor large increase probably due during expansion stroke.