Change ref pressure for bubble scenario

  // const double c_p = 1.005 * 1000;

  const double c_p = gamma / (gamma - 1) * gasConstant;

  const double c_v = 1 / (gamma - 1) * gasConstant;

  const double referencePressure = 10000;

  const double referencePressure = 100000;

  double getGamma() const override;

  double getPr() const override;