Cooling of small size irradiation specimens using impinging jets

To study the effect of irradiation on materials, sample coupons are irradiated in cyclotron facilities. During the irradiation process, these samples produce significant amount of heat. This heat needs to be continuously removed from the samples in order to avoid melting of the samples as well as to keep the samples at a particular temperature during the irradiation process. The area available for heat removal is limited due to the small size of the samples. To increase the heat removal rate, jet cooling is employed as it provides large heat transfer co-efficient. To understand the heat transfer characteristics of jet cooling under these conditions, experiments have been carried out. Electric Joule heating is adopted to simulate irradiation heat in stainless steel samples. Circular / slot nozzles are used to create air jet. From the study the values of the parameters correspond to the maximum heat removal rate are found out. The results are also compared with empirical correlations from the literature.