CFD Analysis of Nozzle Exit Position Effect in Ejector Gas Removal System in Geothermal Power Plant

  • Setyo Nugroho Electronic Engineering Polytechnic Institute of Surabaya
  • Ciptananda Citrahardhani Electronic Engineering Polytechnic Institute of Surabaya


The single stage ejector is used to extract the Non CondensableGas (NCG) in the condenser using the working principle of the Venturi tube. Three dimensional computational simulation of the ejector according to the operating conditions was conducted to determine the flow in the ejector. Motive steam entering through the convergent – divergent nozzle with increasing flow velocity so that the low pressure exist around the nozzle. Comparison is done also in a two dimensional simulation to know the differences occurring phenomena and flow inside ejector. Different simulation results obtained between two dimensional and three dimensional simulation. Reverse flow which occurs in the mixing chamber made the static pressure in the area has increased dramatically. Then the variation performed on Exit Nozzle Position (NXP) to determine the changes of the flow of the NCG and the vacuum level of the ejector.

Keywords: Ejector, NCG, CFD, Compressible flow.


Download data is not yet available.


NurdanYıldırımÖzcan, GüldenGökçen, Performance Analysis of Single-Flash Geothermal Power Plants: Gas Removal Systems Point of View, Proceedings World Geothermal Congress, Bali, pp. 1-2, 2010

Bagus Suherman,Power Electronics, Cahaya Offset (Surabaya), Ed. 1, pp. 11-13, 2003.

Hall, N. R.,Gas extraction system, Lecture notes of Geothermal Utilisation Engineering Geothermal Institute, 1996.

Installation, Operation & Maintenance Manual Nash Model 3/018- 2-0BP Geothermal Gas Removal System Kamojang Geothermal Power Plant

KMJ-20-X2-ES-001-S Rev 3_Specification for Gas Removal, 2007.

P&Id REV 4 ASBUILT, 2007.

Safarudin Dian, Prabowo,SimulasiCFD PadaVariasiTekanan Inlet Nozzle Ejector Terhadap Tingkat Ke-Vacuum-An Steam Ejector Di Unit Pembangkitan Listrik Tenaga Panas Bumi, Thesis, ITS (Surabaya), 2011.

P.H.H. Siregar, . Optimization of electrical power production process for the Sibayak Geothermal Field, Indonesia

Heat Exchange Institute, Standards For Steam Jet Vacuum Systems Fifth edition, Ohio, 2000

Fauzi Soelaiman, a. dkk., Pelaksanaan Evaluasi Performansi Peralatan PLTP Kamojang Unit IV., PT. Gada Energi, 2010

How to Cite
Nugroho, S., & Citrahardhani, C. (2015). CFD Analysis of Nozzle Exit Position Effect in Ejector Gas Removal System in Geothermal Power Plant. EMITTER International Journal of Engineering Technology, 3(1), 68-80.