Exhibit 99.1

    ANSYS AND FLUENT RECEIVE HART-SCOTT-RODINO CLEARANCE FOR PROPOSED MERGER

    SOUTHPOINTE, Pa., April 27 /PRNewswire-FirstCall/ -- ANSYS, Inc.
(Nasdaq: ANSS) and Fluent Inc. today announced that the waiting period under
the Hart-Scott-Rodino Antitrust Improvements Act of 1976, as amended, with
respect to ANSYS' pending acquisition of Fluent expired at 11:59 p.m. (Eastern
Time) on Wednesday, April 26, 2006.  ANSYS expects to close the acquisition by
no later than May 1, 2006.

    As previously announced, ANSYS and Fluent have entered into a definitive
merger agreement in which ANSYS will acquire Fluent in a series of mergers for
6,000,000 shares of its common stock and approximately $300 million in net cash,
subject to certain adjustments at closing.

    "We are very pleased that we have received clearance and look forward to
closing the transaction and implementing our plan," said Jim Cashman, ANSYS
President and CEO. "The combination of ANSYS and Fluent will create substantial
benefits for our global customers, employees, partners and shareholders, through
continued investment and development of innovative products and services, and
our commitment to world-class execution."

    "The ANSYS portfolio of engineering simulation technologies, when combined
with Fluent, will enhance our ability to deliver integration, functionality and
interoperability to a broad set of customers and industries," said Dr. Bharatan
Patel, CEO and founder of Fluent.

    About ANSYS, Inc.
    ANSYS, Inc., founded in 1970, develops and globally markets engineering
simulation software and technologies widely used by engineers and designers
across a broad spectrum of industries. The Company focuses on the development of
open and flexible solutions that enable users to analyze designs directly on the
desktop, providing a common platform for fast, efficient and cost- conscious
product development, from design concept to final-stage testing and validation.
The Company and its global network of channel partners provide sales, support
and training for customers. Headquartered in Canonsburg, Pennsylvania U.S.A.
with more than 25 strategic sales locations throughout the world, ANSYS, Inc.
and its subsidiaries employ approximately 600 people and distribute ANSYS
products through a network of channel partners in over 40 countries. Visit
http://www.ansys.com for more information.

    About Fluent Inc.
    Fluent is a global provider of engineering simulation software technologies
and consulting services. Fluent's software is used for simulation,
visualization, and analysis of fluid flow, heat and mass transfer, flow-induced
noise and chemical reactions utilizing computational fluid dynamics. It is a
vital part of the CAE process for companies around the world and is deployed in
nearly every manufacturing industry. Using Fluent's software, engineers build
virtual prototypes and simulate the performance of proposed and existing
designs, allowing them to improve design quality while reducing cost and
speeding time to market. Fluent's corporate headquarters are located in Lebanon,
New Hampshire, USA, with offices in Belgium, England, France, Germany, India,
Italy, Japan, China and Sweden. For more information visit, www.Fluent.com .



    Certain statements contained in the press release regarding matters that are
not historical facts are "forward-looking" statements (as defined in the Private
Securities Litigation Reform Act of 1995). All forward-looking statements in
this press release are subject to risks and uncertainties. Actual results could
differ materially from those contained in the forward- looking statements and
are based on current expectations that involve a number of risks and
uncertainties, including, but not limited to, the risk that the acquisition of
Fluent may not be consummated or may not be consummated on the timetable that
ANSYS expects, that the business of ANSYS and Fluent may not be integrated
successfully or that such integration may take longer or cost more to accomplish
than expected, that potential difficulties may arise in the assimilation of
operations, strategies, technologies and products of Fluent, that key personnel
of Fluent may not stay with ANSYS, and that management's attention may be
diverted from other business concerns. Additional risks are detailed from time
to time in reports filed by ANSYS, Inc. with the Securities and Exchange
Commission, including ANSYS, Inc.'s 2005 Annual Report and Form 10-K. We
undertake no obligation to publicly update or revise any forward- looking
statements, whether changes occur as a result of new information or future
events after the date they were made.

    ANSYS, ANSYS Workbench, CFX, AUTODYN, and any and all ANSYS, Inc. product
and service names are registered trademarks or trademarks of ANSYS, Inc. or its
subsidiaries located in the United States or other countries. ICEM CFD is a
trademark licensed by ANSYS, Inc. All other trademarks or registered trademarks
are the property of their respective owners.

SOURCE  ANSYS, Inc.
    -0-                             04/27/2006
    /CONTACT:  Lisa O'Connor of ANSYS, Inc., +1-724-514-1782, or
lisa.oconnor@ansys.com /
    /Web site:  http://www.ansys.com
                http://www.Fluent.com /