The Experts below are selected from a list of 23616 Experts worldwide ranked by ideXlab platform

Arun S. Mujumdar - One of the best experts on this subject based on the ideXlab platform.

  • Evaluation of mass transport performance in heterogeneous gaseous in-plane spiral reactors with various Cross-Section geometries at Fixed Cross-Section area
    Chemical Engineering and Processing: Process Intensification, 2014
    Co-Authors: Jundika C. Kurnia, Agus P. Sasmito, Erik Birgersson, Tariq Shamim, Arun S. Mujumdar
    Abstract:

    Abstract Due to its compactness, high heat and mass transfer rate and ease of manufacture, coiled/spiral tube has been widely used in process industries, especially as heat exchangers and chemical reactors. This study addresses the mass-transport enhancement and reaction performance in in-plane spiral reactor with various Cross Sections geometries, i.e. circular, half-circular, rectangular, square, trapezoidal and triangular, at Fixed Cross-Section area at several Reynolds numbers. The mass transfer performance is compared with those of straight channel counterpart. Laminar flow of gas with catalytic reactions is investigated using a validated three-dimensional computational fluid dynamics (CFD) model. The results suggest that spiral ducts offer better reaction performance as compared to straight duct, especially at higher Reynolds number. However, it imposes higher pressure drop. Amongst various Cross-Section, the coil reactor with half-circular geometry yields the highest reaction performance. This study can provide insight for design guidelines of high performance coiled reactor.

  • Numerical analysis of laminar heat transfer performance of in-plane spiral ducts with various Cross-Sections at Fixed Cross-Section area
    International Journal of Heat and Mass Transfer, 2012
    Co-Authors: Agus P. Sasmito, Jundika C. Kurnia, Weijie Wang, Sachin V. Jangam, Arun S. Mujumdar
    Abstract:

    Abstract A numerical approach is carried out to investigate the heat transfer performance of in-plane spiral ducts with various Cross Sections – rectangular, square, triangular, trapezoidal, circular and half circular. Simulations were carried out at a constant inlet Reynolds number at Fixed Cross Section area for both constant wall temperature and constant wall heat flux conditions. Results are compared to straight ducts of the same Cross Sections and at the same length as the coiled ducts. The effects of Reynolds number and Prandtl number are also discussed for various geometries. The results are presented and are aimed to determine the advantages, limitations and effects of in-plane spiral ducts of various Cross Sections on the flow and heat transfer characteristics when the Cross Section area is Fixed.

John R. Adler - One of the best experts on this subject based on the ideXlab platform.

  • Robotic radiosurgery with noncylindrical collimators.
    Computer aided surgery : official journal of the International Society for Computer Aided Surgery, 1997
    Co-Authors: Achim Schweikard, John R. Adler
    Abstract:

    In radiosurgery, a moving beam of radiation acts as an ablative surgical instrument. Conventional systems for radiosurgery use a cylindrical radiation beam of Fixed Cross Section. The radiation source can be moved only along simple, standardized paths. A new radiosurgical system based on a six-degree-of-freedom robotic arm has been developed to overcome limitations of conventional systems. We address the following question: Can dose distributions generated by robotic radiosurgery be improved by using noncylindrical radiation beams? This includes static noncylindrical collimators and collimators of adaptable Cross Section. Geometric methods for planning the shape of the beam in addition to planning beam motion are developed. Design criteria considered in this context are treatment time, radiation penumbra, and transparency of interactive treatment planning. An experimental evaluation compares distributions generated with our new radiosurgical system using cylindrical beams to distributions generated with b...

  • CVRMed - Robotic Radiosurgery with Beams of Adaptable Shapes
    Lecture Notes in Computer Science, 1995
    Co-Authors: Achim Schweikard, Rhea Tombropoulos, John R. Adler
    Abstract:

    In radiosurgery, a moving beam of radiation acts as an ablative surgical instrument. Conventional systems for radiosurgery use a cylindrical radiation beam of Fixed Cross-Section. The radiation source can only be moved along simple standardized paths. A new radiosurgical system based on a six degree-of-freedom robotic arm has been developed to overcome limitations of conventional systems. We address the following question: Can dose distributions generated by robotic radiosurgery be improved by using non-cylindrical radiation beams of adaptable Cross-Section? Geometric methods for planning the shape of the beam in addition to planning beam motion are developed. Design criteria considered in this context are: treatment time, radiation penumbra as well as transparency of interactive treatment planning. An experimental evaluation compares distributions generated with our new radiosurgical system using cylindrical beams to distributions generated with beams of adaptable shapes.

Jundika C. Kurnia - One of the best experts on this subject based on the ideXlab platform.

  • Evaluation of mass transport performance in heterogeneous gaseous in-plane spiral reactors with various Cross-Section geometries at Fixed Cross-Section area
    Chemical Engineering and Processing: Process Intensification, 2014
    Co-Authors: Jundika C. Kurnia, Agus P. Sasmito, Erik Birgersson, Tariq Shamim, Arun S. Mujumdar
    Abstract:

    Abstract Due to its compactness, high heat and mass transfer rate and ease of manufacture, coiled/spiral tube has been widely used in process industries, especially as heat exchangers and chemical reactors. This study addresses the mass-transport enhancement and reaction performance in in-plane spiral reactor with various Cross Sections geometries, i.e. circular, half-circular, rectangular, square, trapezoidal and triangular, at Fixed Cross-Section area at several Reynolds numbers. The mass transfer performance is compared with those of straight channel counterpart. Laminar flow of gas with catalytic reactions is investigated using a validated three-dimensional computational fluid dynamics (CFD) model. The results suggest that spiral ducts offer better reaction performance as compared to straight duct, especially at higher Reynolds number. However, it imposes higher pressure drop. Amongst various Cross-Section, the coil reactor with half-circular geometry yields the highest reaction performance. This study can provide insight for design guidelines of high performance coiled reactor.

  • Numerical analysis of laminar heat transfer performance of in-plane spiral ducts with various Cross-Sections at Fixed Cross-Section area
    International Journal of Heat and Mass Transfer, 2012
    Co-Authors: Agus P. Sasmito, Jundika C. Kurnia, Weijie Wang, Sachin V. Jangam, Arun S. Mujumdar
    Abstract:

    Abstract A numerical approach is carried out to investigate the heat transfer performance of in-plane spiral ducts with various Cross Sections – rectangular, square, triangular, trapezoidal, circular and half circular. Simulations were carried out at a constant inlet Reynolds number at Fixed Cross Section area for both constant wall temperature and constant wall heat flux conditions. Results are compared to straight ducts of the same Cross Sections and at the same length as the coiled ducts. The effects of Reynolds number and Prandtl number are also discussed for various geometries. The results are presented and are aimed to determine the advantages, limitations and effects of in-plane spiral ducts of various Cross Sections on the flow and heat transfer characteristics when the Cross Section area is Fixed.

Achim Schweikard - One of the best experts on this subject based on the ideXlab platform.

  • Robotic radiosurgery with noncylindrical collimators.
    Computer aided surgery : official journal of the International Society for Computer Aided Surgery, 1997
    Co-Authors: Achim Schweikard, John R. Adler
    Abstract:

    In radiosurgery, a moving beam of radiation acts as an ablative surgical instrument. Conventional systems for radiosurgery use a cylindrical radiation beam of Fixed Cross Section. The radiation source can be moved only along simple, standardized paths. A new radiosurgical system based on a six-degree-of-freedom robotic arm has been developed to overcome limitations of conventional systems. We address the following question: Can dose distributions generated by robotic radiosurgery be improved by using noncylindrical radiation beams? This includes static noncylindrical collimators and collimators of adaptable Cross Section. Geometric methods for planning the shape of the beam in addition to planning beam motion are developed. Design criteria considered in this context are treatment time, radiation penumbra, and transparency of interactive treatment planning. An experimental evaluation compares distributions generated with our new radiosurgical system using cylindrical beams to distributions generated with b...

  • CVRMed - Robotic Radiosurgery with Beams of Adaptable Shapes
    Lecture Notes in Computer Science, 1995
    Co-Authors: Achim Schweikard, Rhea Tombropoulos, John R. Adler
    Abstract:

    In radiosurgery, a moving beam of radiation acts as an ablative surgical instrument. Conventional systems for radiosurgery use a cylindrical radiation beam of Fixed Cross-Section. The radiation source can only be moved along simple standardized paths. A new radiosurgical system based on a six degree-of-freedom robotic arm has been developed to overcome limitations of conventional systems. We address the following question: Can dose distributions generated by robotic radiosurgery be improved by using non-cylindrical radiation beams of adaptable Cross-Section? Geometric methods for planning the shape of the beam in addition to planning beam motion are developed. Design criteria considered in this context are: treatment time, radiation penumbra as well as transparency of interactive treatment planning. An experimental evaluation compares distributions generated with our new radiosurgical system using cylindrical beams to distributions generated with beams of adaptable shapes.

Agus P. Sasmito - One of the best experts on this subject based on the ideXlab platform.

  • Evaluation of mass transport performance in heterogeneous gaseous in-plane spiral reactors with various Cross-Section geometries at Fixed Cross-Section area
    Chemical Engineering and Processing: Process Intensification, 2014
    Co-Authors: Jundika C. Kurnia, Agus P. Sasmito, Erik Birgersson, Tariq Shamim, Arun S. Mujumdar
    Abstract:

    Abstract Due to its compactness, high heat and mass transfer rate and ease of manufacture, coiled/spiral tube has been widely used in process industries, especially as heat exchangers and chemical reactors. This study addresses the mass-transport enhancement and reaction performance in in-plane spiral reactor with various Cross Sections geometries, i.e. circular, half-circular, rectangular, square, trapezoidal and triangular, at Fixed Cross-Section area at several Reynolds numbers. The mass transfer performance is compared with those of straight channel counterpart. Laminar flow of gas with catalytic reactions is investigated using a validated three-dimensional computational fluid dynamics (CFD) model. The results suggest that spiral ducts offer better reaction performance as compared to straight duct, especially at higher Reynolds number. However, it imposes higher pressure drop. Amongst various Cross-Section, the coil reactor with half-circular geometry yields the highest reaction performance. This study can provide insight for design guidelines of high performance coiled reactor.

  • Numerical analysis of laminar heat transfer performance of in-plane spiral ducts with various Cross-Sections at Fixed Cross-Section area
    International Journal of Heat and Mass Transfer, 2012
    Co-Authors: Agus P. Sasmito, Jundika C. Kurnia, Weijie Wang, Sachin V. Jangam, Arun S. Mujumdar
    Abstract:

    Abstract A numerical approach is carried out to investigate the heat transfer performance of in-plane spiral ducts with various Cross Sections – rectangular, square, triangular, trapezoidal, circular and half circular. Simulations were carried out at a constant inlet Reynolds number at Fixed Cross Section area for both constant wall temperature and constant wall heat flux conditions. Results are compared to straight ducts of the same Cross Sections and at the same length as the coiled ducts. The effects of Reynolds number and Prandtl number are also discussed for various geometries. The results are presented and are aimed to determine the advantages, limitations and effects of in-plane spiral ducts of various Cross Sections on the flow and heat transfer characteristics when the Cross Section area is Fixed.