BARROSO, A.C.O.BAPTISTA FILHO, B.D.PALMIERI, E.T.SABUNDJIAN, G.ANDRADE, D.A.MACEDO, L.A.2014-11-172014-11-182015-04-022014-11-172014-11-182015-04-02BARROSO, A.C.O.; BAPTISTA FILHO, B.D.; PALMIERI, E.T.; SABUNDJIAN, G.; ANDRADE, D.A.; MACEDO, L.A. CNEN in the IRIS Project. In: LAS-ANS SYMPOSIUM 2002 - POWER SUPPLY AND ITS PROBLEMS: THE NUCLEAR PROPOSAL, June 17-20, 2002, Rio de Janeiro, RJ. Disponível em: http://repositorio.ipen.br/handle/123456789/16288.http://repositorio.ipen.br/handle/123456789/16288IRIS, the International Reactor Innovative and Secure is an international development program of an innovative, water cooled reactor designed to meet the requirements of proliferation resistance, enhanced safety, cost effectiveness, modular deployment, innovative waste management and high efficiency fuel. By the end of 2001 CNEN signed a collective agreement with Westinghouse Electric Company to officially participate in the development of this integral primary system reactor (IPSR). CNEN team is responsible for the internal pressurizer design and for the independent review of RELAP 5 input file. The design tasks for the pressurizer have included steam-water volume sizing, pressurizer to vessel physical separation, thermal insulation and surge connections dimensioning. Future work will address the need of passive spray devices, honeycomb insulation and surge baffles. This paper present some of the most relevant characteristics of the IRIS design and the preliminary results of pressurizer design, operating modes analysis and transients analysis with RELAP 5.openAccessreactorspwr type reactorscooperationbrazilian cnenpressurizersdesignr codesreactor safetyTexto completo de eventohttps://orcid.org/0000-0002-6689-3011https://orcid.org/0000-0001-9544-4509